Lithium Americas 20-F 18 Mar 24 2023 FY Annual report (foreign) Financial data

Document and Entity Information

Document and Entity Information	12 Months Ended
	Dec. 31, 2023 shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Trading Symbol	LAC
Entity Registrant Name	LITHIUM AMERICAS CORP.
Entity Central Index Key	0001966983
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Voluntary Filers	No
Entity Shell Company	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Shares without par value
Security Exchange Name	NYSE
Entity File Number	001-41788
Entity Incorporation, State or Country Code	A1
Entity Address, Country	CA
Entity Address, Address Line One	400 - 900 West Hastings Street
Entity Address City Or Town	Vancouver
Entity Address State Or Province	BC
Entity Address Postal Zip Code	V6C 1E5
Document Annual Report	true
Document Transition Report	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Document Accounting Standard	International Financial Reporting Standards
Document Registration Statement	false
Document Shell Company Report	false
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Vancouver, British Columbia, Canada
Auditor Firm ID	271
Entity Common Stock, Shares Outstanding	161,778,274
Business Contact [Member]
Document Information [Line Items]
Entity Address, Address Line One	400 - 900 West Hastings Street
Entity Address City Or Town	Vancouver
Entity Address State Or Province	BC
Entity Address Postal Zip Code	V6C 1E5
City Area Code	778
Local Phone Number	656-5820
Contact Personnel Name	Edward Grandy

Consolidated Statements of Fina

Consolidated Statements of Financial Position $ in Thousands, $ in Millions	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
CURRENT ASSETS
Cash and cash equivalents	$ 195,516	$ 636	$ 933
Receivables, prepaids and deposits	10,367	1,301	878
Total current assets	205,883	1,937	1,811
NON-CURRENT ASSETS
Investment in Green Technology Metals	2,580	7,451	0
Investment in Ascend Elements	8,582	5,000	0
Restricted cash	288	0	0
Property, plant and equipment	206,082	3,936	3,294
Other assets	15,315	0	0
Exploration and evaluation assets	770	9,514	5,747
Total non-current assets	233,617	25,901	9,041
TOTAL ASSETS	439,500	27,838	10,852
CURRENT LIABILITIES
Accounts payable and accrued liabilities	23,361	9,913	4,214
Current portion of long-term liabilities	854	724	303
GM transaction derivative liability	348	0	0
Loan from former parent	0	43,572	0
Total current liabilities	24,563	54,209	4,517
LONG-TERM LIABILITIES
Loan from former parent	0	0	40,000
Other liabilities	6,613	7,568	7,695
Decommissioning provision	862	478	326
Total Long-term liabilities	7,475	8,046	48,021
TOTAL LIABILITIES	32,038	62,255	52,538
SHAREHOLDERS' EQUITY
Share capital	656,802	0	0
Contributed surplus and net former parent investment	15,020	226,009	150,942
Deficit	(264,360)	(260,426)	(192,628)
TOTAL SHAREHOLDERS' EQUITY	407,462	(34,417)	(41,686)
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 439,500	$ 27,838	$ 10,852

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of comprehensive income [abstract]
Exploration and evaluation expenditures	$ (3,763)	$ (47,275)	$ (36,113)
General and administrative expenses	(16,274)	(9,545)	(5,116)
Equity compensation	(7,588)	(4,037)	(3,266)
Total expense	(27,625)	(60,857)	(44,495)
Transaction costs	(10,541)	0	0
Gain (loss) on financial instruments measured at fair value	31,557	(2,564)	0
Finance costs	(348)	(4,039)	(2,651)
Finance and other income (expenses)	3,023	(338)	(2)
Total operating income	23,691	(6,941)	(2,653)
NET LOSS BEFORE DISCONTINUED OPERATION	(3,934)	(67,798)	(47,148)
Income from discontinued operation	0	0	122
NET LOSS	(3,934)	(67,798)	(47,026)
TOTAL COMPREHENSIVE LOSS	$ (3,934)	$ (67,798)	$ (47,026)
BASIC LOSS PER SHARE FROM CONTINUING OPERATIONS	$ (0.02)	$ (0.42)	$ (0.29)
DILUTED LOSS PER SHARE FROM CONTINUING OPERATIONS	(0.02)	(0.42)	(0.29)
BASIC LOSS PER SHARE	(0.02)	(0.42)	(0.29)
DILUTED LOSS PER SHARE	$ (0.02)	$ (0.42)	$ (0.29)
WEIGHTED AVERAGE NUMBER OF COMMON SHARES OUTSTANDING, BASIC AND DILUTED	160,363	160,048	160,048

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Share capital	Contributed surplus and net former parent investment	Deficit
Beginning balance, Shares at Dec. 31, 2020		0
Beginning balance at Dec. 31, 2020	$ (12,710)	$ 0	$ 132,892	$ (145,602)
Net former parent investment	18,050		18,050
Net loss	(47,026)			(47,026)
Ending balance, Shares at Dec. 31, 2021		0
Ending balance at Dec. 31, 2021	(41,686)	$ 0	150,942	(192,628)
Net former parent investment	75,067		75,067
Net loss	(67,798)			(67,798)
Ending balance, Shares at Dec. 31, 2022		0
Ending balance at Dec. 31, 2022	(34,417)	$ 0	226,009	(260,426)
Net former parent investment	57,301		57,301
General Motors transaction	271,737		271,737
Share transactions pursuant to Arrangement		160,048
Share transactions pursuant to Arrangement	113,779	$ 649,867	(536,088)
Shares issued on conversion of share-based awards, Shares		1,730
Shares issued on conversion of share-based awards		$ 6,935	(6,935)
Equity compensation amortization	2,996		2,996
Net loss	(3,934)			(3,934)
Ending balance, Shares at Dec. 31, 2023		161,778
Ending balance at Dec. 31, 2023	$ 407,462	$ 656,802	$ 15,020	$ (264,360)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
OPERATING ACTIVITIES
Loss from continuing operations	$ (3,934)	$ (67,798)	$ (47,148)
Income from discontinued operation	0	0	122
NET LOSS	(3,934)	(67,798)	(47,026)
Items not affecting cash and other items:
Equity compensation	5,581	2,355	1,797
Depreciation	196	1,520	658
(Gain)/loss on financial instruments measured at fair value	(31,557)	2,564	0
Other items	83	516	119
Changes in working capital items:
Increase in receivables, prepaids and deposits	(4,907)	(423)	(525)
Increase/(decrease) in accounts payable, accrued liabilities and other liabilities	(3,424)	9,271	2,551
Cash used by discontinued operations	0	0	(511)
Net cash used in operating activities	(37,962)	(51,995)	(42,937)
INVESTING ACTIVITIES
Release on restricted cash	0	0	150
Additions to property, plant and equipment	(189,481)	(1,505)	(529)
Additions to exploration and evaluation assets	(347)	(4,120)	(1,405)
Restricted cash invested in GIC	(288)
Investment in Green Technology Metals	0	(10,015)	0
Investment in Ascend Elements	0	(5,000)	0
Proceeds from sale of assets held for sale (discontinued operations)	0	0	4,034
Net cash (used)/provided in investing activities	(190,116)	(20,640)	2,250
FINANCING ACTIVITIES
Net former parent investment - capital contributions	45,501	72,712	20,115
Gross proceeds from GM transaction	320,148
Cash received pursuant to the Arrangement	75,000	0	0
Payment of expenses related to the GM transaction	(16,977)	0	0
Loan from former parent	0	0	23,512
Payment of interest on loan from former parent	0	0	(3,017)
Lease payments	(714)	(374)	(263)
Other	0	0	761
Net cash provided by financing activities	422,958	72,338	41,108
CHANGE IN CASH AND CASH EQUIVALENTS	194,880	(297)	421
CASH AND CASH EQUIVALENTS - BEGINNING OF THE YEAR	636	933	512
Cash and cash equivalents as presented in the Statements of Cash Flows	$ 195,516	$ 636	$ 933

Background and Nature of Operat

Background and Nature of Operations	12 Months Ended
	Dec. 31, 2023
General information about financial statements [abstract]
Background and Nature of Operations	1. BACKGROUND AND NATURE OF OPERATIONS 1397468 B.C. Ltd. was incorporated under the Business Corporations Act (British Columbia) on January 23, 2023 for the sole purpose of acquiring ownership of the North American business assets and investments of an entity then named Lithium Americas Corp. (“ Old LAC ”) and, which is now named Lithium Americas (Argentina) Corp (“ Lithium Argentina ”), pursuant to a separation transaction (the “ Separation ”) as described in Note 2. The assets, liabilities and activities of Old LAC's North American business prior to the Separation, are referred to as LAC North America. Upon consummation of the Separation on October 3, 2023, 1397468 B.C. Ltd. was re-named Lithium Americas Corp. (“ New LAC” or the “ Company ”) and its common shares were listed on the Toronto Stock Exchange (“ TSX ”) and on the New York Stock Exchange (“ NYSE ”) under the symbol “LAC.” These financial statements are presented on a continuity of interests basis and reflect the activities of the Company from October 3, 2023 and the activities of LAC North America prior to that date and for the comparative periods presented. Prior to October 3, 2023, LAC North America did not operate as a separate legal entity. The Company is focused on advancing the Thacker Pass project (" Thacker Pass "), a sedimentary-based lithium project located in the McDermitt Caldera in Humboldt County in north-western Nevada, USA. Thacker Pass is 100 %-owned by Lithium Nevada Corp., which is wholly owned by 1339840 B.C. Ltd., a wholly-owned subsidiary of the Company. The head office and principal address of the Company is Suite 400, 900 West Hastings Street, Vancouver, British Columbia, Canada, V6C 1E5. On January 30, 2023, LAC North America entered into a purchase agreement with General Motors Holdings LLC (“ GM ”) pursuant to which GM agreed to make a $ 650 million investment (the “ Transaction ”), the proceeds of which are to be used for the construction and development of Thacker Pass. The Transaction is comprised of two tranches, with the $ 320.1 million first tranche investment (the “ Tranche 1 Investment ”) and a second tranche investment of up to $ 329.9 million (the “ Tranche 2 Investment” ). The Tranche 1 Investment was completed on February 16, 2023 resulting in GM owning 15,002 common shares of Old LAC which became an equivalent number of shares of the Company post - Separation. On March 12, 2024, the Company received a conditional commitment (“ Conditional Commitment ”) from the U.S. Department of Energy (“ DOE ”) for a $ 2.26 billion loan under the Advanced Technology Vehicles Manufacturing (“ ATVM ”) Loan Program (the “ DOE Loan ”), for financing the construction of the processing facilities at Thacker Pass. While this Conditional Commitment represents a significant milestone and demonstrates the DOE’s intent to finance Thacker Pass, certain technical, legal and financial conditions, including negotiation of definitive financing documents, must be satisfied before funding of the DOE Loan. There can be no assurances as to the terms and conditions of the definitive financing documents or whether the financing will be finalized. To date, the Company has not generated significant revenues from operations and has relied on equity financings to fund operations. The underlying values of exploration and evaluation assets, property, plant and equipment and the investment in Thacker Pass are dependent on the existence of economically recoverable reserves, securing and maintaining title and beneficial interest in the properties, and the ability of the Company to obtain the necessary financing to complete development, and to attain future profitable operations.

Reorganization

Reorganization	12 Months Ended
	Dec. 31, 2023
Disclosure of reorganization [abstract]
Reorganization	2. REORGANIZATION The Separation was completed pursuant to a statutory plan of arrangement (the " Arrangement "). Under the terms of the Arrangement, Old LAC contributed to New LAC, the assets of LAC North America, including Thacker Pass, investments in shares of certain companies, its receivable of $ 43.6 million plus accrued interest to October 3, 2023 and cash of $ 275.5 million (which included the remaining unspent proceeds of the Tranche 1 Investment and $ 75 million to establish sufficient working capital). Each shareholder of Old LAC was granted one common share in Lithium Argentina and one common share of New LAC in exchange for each Old LAC share, resulting in two independent publicly traded companies. The Separation was pro rata to the shareholders of Old LAC, so that the holders maintained the same proportionate interest in Old LAC (and, upon the Separation, Lithium Argentina's) and New LAC both immediately before and after the Separation. As the Separation was completed before the closing of the Tranche 2 Investment, the Tranche 2 agreement between GM and Old LAC was terminated on October 3, 2023 and replaced by a corresponding subscription agreement between GM and New LAC (the " Tranche 2 Investment Agreement ") (see Note 11) such that the proceeds will be received by the Company. As part of the Separation, an investors rights agreement and an agreement to supply GM with lithium carbonate production from Thacker Pass (the " Offtake Agreement ") were assigned by Old LAC to the Company. Share transactions pursuant to the Arrangement are as follows: $ Cash transferred to establish sufficient working capital pursuant to the Arrangement 75,000 Loan from former parent contributed pursuant to the Arrangement 46,258 Share issuance costs pursuant to the Arrangement ( 7,479 ) 113,779

Basis of Preparation and Presen

Basis of Preparation and Presentation	12 Months Ended
	Dec. 31, 2023
Basis of Preparation and Presentation [Abstract]
Basis of Preparation and Presentation	3. BASIS OF PREPARATION AND PRESENTATION These consolidated financial statements have been prepared in accordance with IFRS Accounting Standards as issued by the International Accounting Standards Board ("IFRS") issued and outstanding as of December 31, 2023. These consolidated financial statements reflect the activities of the Company from October 3, 2023 and the activities of LAC North America on a "carve-out" basis prior to that date and for the comparative periods presented. Prior to October 3, 2023, LAC North America did not operate as a separate legal entity. The assets, liabilities, results of operations and cash flows prior to October 3, 2023 were those specifically identifiable to LAC North America including assets, liabilities and expenses relating to Thacker Pass, specified investments, transactions and balances arising from the GM investment, as well as an allocation of certain costs relating to the management of those relevant assets, liabilities and results of operations. Such costs have been allocated from the shared corporate expenses of Old LAC based on the estimated level of involvement of Old LAC management and employees with LAC North America. 3. BASIS OF PREPARATION AND PRESENTATION (continued) For the period prior to October 3, 2023, these consolidated financial statements present the financial position, results of operations, changes in shareholders' equity and cash flows of the Company as if it had operated on a stand-alone basis. During these periods, Old LAC costs were allocated to LAC North America for corporate administrative expenses and employment costs of Old LAC employees primarily relating to Old LAC employees who provided services including accounting and finance, legal, information technology, human resources, marketing, investor relations, contract support, treasury, administrative and other corporate head office services. The expenses and cost allocations have been determined on a basis considered by Old LAC to be a reasonable reflection of the utilization of services provided to or the benefit received by LAC North America during the periods presented relative to the total costs incurred by Old LAC.

Summary of Material Accounting

Summary of Material Accounting Policies	12 Months Ended
	Dec. 31, 2023
Disclosure of summary of materials policies [abstract]
Summary of Material Accounting Policies	4. SUMMARY OF MATERIAL ACCOUNTING POLICIES Principles of Consolidation These consolidated financial statements include the accounts of the Company and its corporate group of companies, consisting of (i) wholly-owned US subsidiaries Lithium Nevada, RheoMinerals Inc., and KV project LLC; and (ii) Canadian wholly-owned subsidiary 1339480 B.C. Ltd. All intercompany transactions and balances have been eliminated. Subsidiaries are all entities over which the Company has control. The Company controls an entity when the group is exposed to, or has rights to, variable returns from its involvement with the entity and has the ability to affect those returns through its power to direct the activities of the entity. Subsidiaries are fully consolidated from the date on which control is transferred to the Company. They are deconsolidated from the date that control ceases. Intercompany transactions, balances and unrealized gains on transactions between group companies are eliminated. Foreign Currency Translation Functional and Presentation Currency Items included in the financial statements of each of the entities are measured using the currency of the primary economic environment in which the entity operates (the functional currency). The consolidated financial statements are presented in US dollars. The functional currency of the Company, as well as all subsidiaries, is the US dollar. Transactions and Balances Foreign currency transactions are translated into the functional currency using the exchange rates at the dates of the transactions. Foreign exchange gains and losses resulting from the settlement of such transactions and from the translation of monetary assets and liabilities denominated in foreign currencies at year end exchange rates are generally recognized in profit or loss. Non-monetary items measured at historical cost continue to be carried at the exchange rate at the date of the transaction. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Cash and Cash Equivalents Cash and cash equivalents consist of cash held with banks and highly liquid short-term investments which can be withdrawn at any time and are subject to an insignificant risk of changes in value. Exploration and Evaluation Assets Exploration expenditures excluding acquisition costs and claim maintenance costs are expensed until the establishment of technical feasibility and commercial viability based on a combination of the following factors: • The extent to which mineral reserves or mineral resources as defined in National Instrument 43-101 (“ NI 43-101 ”) have been identified through a feasibility study or similar document; and, • The status of mining leases, environmental and mining permits. Costs incurred relating to the acquisition and claim maintenance of mineral properties, including option payments and annual fees to maintain the property in good standing, and exploration expenditures performed within the geologic formation of an existing brownfield mining project are capitalized and deferred by property until the project to which they relate is sold, abandoned, impaired, or placed into production. The Company assesses its exploration and evaluation assets for indications of impairment on each balance sheet date and when events and circumstances indicate a risk of impairment. A property is written down or written off when the Company determines that an impairment of value has occurred or when exploration results indicate that no further work is warranted. Exploration and evaluation assets are tested for impairment immediately prior to reclassification to mineral property development costs. Property, Plant and Equipment On initial recognition, property, plant and equipment are valued at cost. Cost includes the purchase price and directly attributable cost of acquisition or construction required to bring the asset to the location and condition necessary to be capable of operating in the manner intended by the Company, including appropriate borrowing costs and foreign exchange losses or gains on borrowings and related cash used to construct qualifying assets as defined under IFRS. Capitalization of costs incurred ceases when the asset is capable of operating in the manner intended by management. The Company applies judgment in its assessment of when the asset is capable of operating in the manner intended by management. Property, plant and equipment are subsequently measured at cost less accumulated depreciation, less any accumulated impairment losses, with the exception of land which is not depreciated. When parts of an item of property, plant and equipment have different useful lives, they are accounted for as separate items or major components. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Property, plant and equipment that are currently in use are depreciated as follows: • Process testing facility equipment included in “Equipment and machinery” – straight-line basis over the estimated useful life of 10 years; • Right-of-use assets – depreciated over the shorter of the asset’s useful life and the lease term on a straight-line basis; and • Office equipment included in “Other” – declining balance method at 20 % annual rate. The assets’ residual values, useful lives and depreciation methods are reviewed and adjusted, if appropriate, at least annually. The gain or loss arising on the disposal of an item of property, plant and equipment is determined as the difference between the sale proceeds and the carrying amount of the asset and is recognized in profit and loss. Impairment of Property, Plant and Equipment Property, plant and equipment are assessed for impairment indicators at each reporting date or when an impairment indicator arises if not at a reporting date. If an impairment indicator is identified, an impairment assessment is carried out. If an impairment loss is identified, it is recognized for the amount by which the asset’s carrying amount exceeds its recoverable amount. The recoverable amount is the higher of an asset’s fair value less cost of disposal and value in use. Fair value is determined as the amount that would be obtained from the sale of the asset in an arm’s length transaction between knowledgeable and willing parties. In assessing value in use, the estimated future cash flows are discounted to their present value using a pre-tax discount rate that reflects current market assessments of the time value of money and the risks specific to the asset. For the purposes of assessing impairment, assets are grouped at the lowest levels for which there are separately identifiable cash flows (cash-generating units). These are typically individual mines or development projects. Where the factors which resulted in an impairment loss subsequently reverse, the carrying amount of the asset (or cash-generating unit) is increased to the revised estimate of its recoverable amount, but to an amount that does not exceed the carrying amount that would have been determined had no impairment loss been recognized for the asset (or cash-generating unit) in prior years. A reversal of an impairment loss is recognized immediately in profit or loss. Leases At inception of a contract, the Company assesses whether a contract is, or contains, a lease. A contract is, or contains, a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company leases office space, equipment, vehicles and land. Lease contracts entered into by the Company are typically made for fixed periods of 2 to 5 years, with the exception of land leases which have a term of 40 years. Lease terms are negotiated on an individual basis and contain a wide range of different terms and conditions. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Leases are recognized as a right-of-use asset and a corresponding liability at the date at which the leased asset is available for use by the Company. Payments associated with short-term leases and leases of low-value assets are recognized on a straight-line basis as an expense in profit or loss. Short-term leases are leases with a lease term of 12 months or less. Financial Instruments Financial assets and liabilities are recognized when the Company becomes a party to the contractual provisions of the instrument. On initial recognition, financial assets are classified as and measured at: amortized cost, fair value through profit or loss (“FVTPL”) or fair value through OCI according to their contractual cash flow characteristics and the business models under which they are held. The Company’s investments in equity investments are classified as FVTPL. Investments in equity instruments are held for strategic purposes and classified as long term. Financial assets are measured at amortized cost if they are held for the collection of contractual cash flows where those cash flows solely represent payments of principal and interest and; the Company’s intent is to hold these financial assets in order to collect contractual cash flows. Financial liabilities are measured at amortized cost unless they are required to be measured at FVTPL. Financial assets are derecognized when the rights to receive cash flows from the assets have expired or have been transferred and the Company has transferred substantially all risks and rewards of ownership. Derivative instruments Derivative instruments, including embedded derivatives in executory contracts or financial liability contracts, are classified as at FVTPL, and recorded on the balance sheet at fair value. Unrealized gains and losses on derivatives not designated in a hedging relationship are recorded as part of income (expense). Fair values for derivative instruments are determined using inputs based on market conditions existing at the balance sheet date or settlement date of the derivative. Derivatives embedded in non-derivative contracts are recognized separately unless they are closely related to the host contract. Impairment of financial assets The Company assesses on a forward-looking basis the expected credit losses associated with its financial assets carried at amortized cost. The impairment methodology applied depends on whether there has been a significant increase in credit risk. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Provisions Provisions are recognized when the Company has a present obligation, legal or constructive, as a result of a past event, it is probable that an outflow of resources embodying economic benefits will be required to settle the obligation and a reliable estimate can be made of the amount of the obligation. If the effect of the time value of money is material, provisions are determined by discounting the expected future cash flows at a pre-tax rate that reflects current market assessments of the time value of money and, where appropriate, the risks specific to the liability. Where discounting is used, the increase in the provision due to the passage of time is recognized as a finance cost. Close down and restoration costs include dismantling and demolition of infrastructure and the removal of residual materials and remediation of disturbed areas. Estimated close down and restoration costs are provided for in the accounting period when the obligation arising from the related disturbance occurs, based on the net present value of estimated future costs. The cost estimates are updated during the life of the operation to reflect known developments, such as revisions to cost estimates and to the estimated lives of the operations and are subject to formal reviews at regular intervals. The initial closure provision together with changes resulting from changes in estimated cash flows or discount rates are capitalized within capital assets. These costs are then depreciated over the lives of the asset to which they relate, typically using the units of production method. The amortization or unwinding of the discount applied in establishing the net present value of provisions is charged to the statement of comprehensive (loss)/income as a financing cost. Provision is made for the estimated present value of the costs of environmental cleanup obligations outstanding at the statement of financial position date. Income Taxes Income taxes are comprised of current and deferred tax. Income tax is recognized in profit or loss except to the extent that it relates to items recognized directly in equity. Current tax expense is the expected tax payable on taxable income for the year, using tax rates enacted or substantively enacted at period-end, adjusted for amendments to tax payable with regards to previous years. Deferred tax is recorded using the liability method, providing for temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for taxation purposes. Temporary differences are not provided for the initial recognition of assets or liabilities that affect neither accounting or taxable loss, unless arising in a business combination, nor for differences relating to investments in subsidiaries to the extent that they are not probable to reverse in the foreseeable future. The amount of deferred tax provided is based on the expected manner of realization or settlement of the carrying amount of assets and liabilities, using tax rates enacted or substantively enacted at the statement of financial position date. A deferred tax asset is recognized only to the extent that it is probable that future taxable profits will be available against which the asset can be utilized. To the extent that the Company does not consider it probable that a deferred tax asset will be recovered, the deferred tax asset is not recorded. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Share Capital Common shares are classified as equity. Incremental costs directly attributable to the issuance of shares are recognized as a deduction from equity. Earnings/(Loss) per Share Basic earnings/(loss) per share is computed by dividing the net earnings or loss attributable to shareholders of the Company by the weighted average number of common shares outstanding during the reporting period. For periods presented on a "carve-out" basis, the number of shares issued and outstanding upon Separation is used as the denominator in the calculation of basic earnings/(loss) per share. The diluted earnings/(loss) per share calculation is based on the weighted average number of common shares outstanding during the period, plus the effects of dilutive common share equivalents. This method requires that the dilutive effect of outstanding options and warrants issued should be calculated using the treasury stock method. This method assumes that all common share equivalents have been exercised at the beginning of the period (or at the time of issuance, if later), and that the funds obtained thereby were used to purchase common shares of the Company at the average trading price of the common shares during the period, but only if dilutive. Equity-Based Compensation The Company’s equity incentive plan allows the grant of stock options, restricted share units ("RSUs"), performance share units (PSUs") and deferred share units ("DSUs"). The cost of equity-settled payment arrangements is recorded based on the estimated fair value at the grant date and charged to earnings over the vesting period. Each tranche in an award is considered a separate award with its own vesting period and grant date fair value. The fair value of each tranche is measured at the date of grant using Monte Carlo simulation methodology for performance share units. Compensation expense is recognized over the tranche’s vesting period based on the number of awards expected to vest, by increasing contributed surplus. The number of awards expected to vest is reviewed at least annually with any impact being recognized immediately. Where equity instruments are granted to non-employees, they are recorded at the fair value of the goods or services received in the statement of comprehensive (loss)/income, unless they are related to the issuance of equity instruments. Amounts related to the issuance of shares are recorded as a reduction of share capital. When the value of goods or services received in exchange for the share-based payment cannot be reliably estimated, the fair value is measured by use of a valuation model. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Estimation Uncertainty and Significant Accounting Policy Judgments The preparation of these consolidated financial statements require management to make assumptions, estimates, and judgments that affect the amounts reported in these financial statements and accompanying notes. The Company bases its estimates on historical experience and various assumptions that are believed to be reasonable at the time the estimate was made. Accordingly, actual results may differ from amounts estimated in these consolidated financial statements and such differences could be material. Significant accounting policy judgments in the preparation of the Company's financial statements are as follows: Accounting for the Agreements with General Motors The Company’s accounting for the agreements with General Motors involved judgment, specifically in its assumption that in determination the Offtake Agreement represents an agreement with market selling prices; and that the Offtake is separate from the equity financing provided by GM (see Note 11). The second tranche investment component of subscription agreements with GM which involved estimation of fair value, utilizes a Monte Carlo simulation that required significant assumptions, including expected volatility of Old LAC’s (and, following Separation, New LAC’s) share price, an estimated risk-free rate and an estimated dividend. Commencement of Development of Thacker Pass The Company determined that the technical feasibility and commercial viability of Thacker Pass had been demonstrated following the release of an independent National Instrument 43-101 feasibility study (the “ Thacker Pass Feasibility Study ”) on January 31, 2023, the receipt of the favorable ruling from the U.S. District Court, District of Nevada (“U.S. District Court ”) for the issuance of the Record of Decision (“ ROD ”), and the receipt of notice to proceed from the Bureau of Land Management (“ BLM ”) on February 7, 2023. The Company entered into an engineering, procurement and construction management agreement and other construction-related contracts. Construction of Thacker Pass, including site preparation, geotechnical drilling, water pipeline development and associated infrastructure commenced. Accordingly, the capitalized costs of Thacker Pass were transferred to property, plant and equipment from exploration and evaluation assets and capitalization of development costs commenced February 1, 2023. Concurrent with the transfer of the Thacker Pass assets from exploration and evaluation to property, plant and equipment, the Company completed an impairment test of Thacker Pass which compared the carrying value to the recoverable amount. The recoverable amount is the greater of the value in use and the fair value less disposal costs. The fair value less disposal costs is calculated using a discounted cash flow model with feasibility study economics. The significant assumptions that impacted the fair value included future lithium prices, capital cost estimates, operating cost estimates, estimated mineral reserves and resources, and the discount rate. Management applied judgment in conducting the impairment test and concluded that there was no impairment. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Assessment of Impairment of Thacker Pass The Company applied judgment in carrying out an evaluation of Thacker Pass for indicators of impairment at December 31, 2023. The Company carried out the evaluation considering internal and external factors including but not limited to, the Thacker Pass November 2022 Feasibility Study including assumptions and sensitivity analysis, market trends in lithium prices, discount rates, trends in financial markets and the Company's market capitalization. New IFRS Pronouncements Amendments to IAS 1 – Presentation of Financial Statements In October 2022, the IASB issued amendments to IAS 1, Presentation of Financial Statements titled Non-current Liabilities with Covenants. These amendments sought to improve the information that an entity provides when its right to defer settlement of a liability is subject to compliance with covenants within 12 months after the reporting period. These amendments to IAS 1 override but incorporate the previous amendments, Classification of liabilities as current or non-current, issued in January 2020, which clarified that liabilities are classified as either current or non-current, depending on the rights that exist at the end of the reporting period. Liabilities should be classified as non-current if a company has a substantive right to defer settlement for at least 12 months at the end of the reporting period. The amendments are effective January 1, 2024, with early adoption permitted. Retrospective application is required on adoption. These amendments are not expected to have a material effect on the financial statements of the Company. Amendment to IAS 1 and IFRS Practice Statement 2 – Disclosure of Accounting Policies In February 2021, the IASB issued amendments to IAS 1, “Presentation of Financial Statements” and the IFRS Practice Statement 2 “Making Materiality Judgments” to provide guidance on the application of materiality judgments to accounting policy disclosures. The amendments to IAS 1 replace the requirement to disclose significant accounting policies with a requirement to disclose material accounting policies. Guidance and illustrative examples are added in the Practice Statement to assist in the application of the materiality concept when making judgments about accounting policy disclosures. The amendments were effective January 1, 2023. These amendments did not impact these consolidated financial statements. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Amendments to IAS 12 – International Tax Reform Pillar Two Model Rules In May 2023, the IASB issued amendments to IAS 12, International Tax Reform - Pillar Two Model Rules to clarify the application of IAS 12 Income Taxes to income taxes arising from tax law enacted or substantively enacted to implement the Organization for Economic Co-operation and Development (OECD)/G20 Inclusive Framework on Base Erosion and Profit Shifting (BEPS) Pillar Two model rules (Pillar Two income taxes). The amendments introduce a mandatory temporary exception to the accounting for deferred taxes arising from the jurisdictional implementation of the Pillar Two model rules and disclosure requirements for the entities to help users of the financial statements better understand an entity’s exposure to Pillar Two income taxes arising from that legislation, particularly before its effective date. The mandatory temporary exception, the use of which is required to be disclosed, applies immediately. The remaining disclosure requirements apply for annual reporting periods beginning on or after January 1, 2023, but not for any interim periods ending on or before December 31, 2023. These amendments did not impact these consolidated financial statements.

Cash and Cash Equivalents

Cash and Cash Equivalents	12 Months Ended
	Dec. 31, 2023
Cash and cash equivalents [abstract]
Cash and Cash Equivalents	5. CASH AND CASH EQUIVALENTS December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Cash 12,050 636 933 Cash equivalents 183,466 - - 195,516 636 933 On October 3, 2023, cash and cash equivalents included the remaining unspent net proceeds of the Tranche 1 Investment plus an additional $ 75 million in cash that was transferred from Old LAC to New LAC to establish sufficient working capital for New LAC, pursuant to the Arrangement (see Note 2). As at December 31, 2023, $ 8.5 million of cash and cash equivalents were held in Canadian dollars (December 31, 2022 – $ nil ), and $ 187.0 million in US dollars (December 31, 2022 – $ 0.6 million). Cash equivalents include investments in guaranteed investment certificates (“ GIC s”) with a Canadian Schedule I chartered bank that mature within three months from the date of acquisition and earn interest between 3 %- 5.5 % per annum and investments in US treasury bills, short-term savings and deposit accounts with a Canadian Schedule I chartered bank.

Receivables, Prepaids and Depos

Receivables, Prepaids and Deposits	12 Months Ended
	Dec. 31, 2023
Prepaids, deposits and receivables [abstract]
Receivables, prepaids and deposits	6. RECEIVABLES, PREPAIDS AND DEPOSITS December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Prepaids and deposits 5,872 1,298 754 Receivables 2,922 3 124 Interest receivable 1,573 - - 10,367 1,301 878 Receivables include amounts receivable from Lithium Argentina (Note 15).

Investment in Green Technology

Investment in Green Technology Metals	12 Months Ended
	Dec. 31, 2023
Disclosure of interest in other entities [abstract]
Investment in Green Technology Metals	7. INVESTMENT IN GREEN TECHNOLOGY METALS On April 28, 2022, LAC North America entered into an agreement to acquire shares of Green Technology Metals Limited (ASX: GT1) (“ Green Technology Metals ”), a North American focused lithium exploration and development public company with hard rock spodumene assets in north-western Ontario, Canada, in a private placement for total consideration of $ 10,000 . As at December 31, 2023, the Company holds 13,301 common shares, representing approximately 4 % of the issued and outstanding shares of Green Technology Metals with a fair value of $ 2,580 (December 31, 2022 - $ 7,451 ) determined based on the market price of Green Technology Metals’ shares as of such date. A loss on change in fair value of Green Technology Metals Shares of $ 4,871 at December 31, 2023 (2022 - $ 2,564 ) was recognized in the Consolidated Statements of Comprehensive Loss. The Company’s investment in Green Technology Metals is classified as a Level 1 financial instrument (Note 24).

Investment in Ascend Elements

Investment in Ascend Elements	12 Months Ended
	Dec. 31, 2023
Disclosure of joint operations [abstract]
Investment in Ascend Elements	8. INVESTMENT IN ASCEND ELEMENTS On July 18, 2022, LAC North America made a $ 5,000 investment in Ascend Elements, Inc. (“ Ascend Elements ”), a private US based lithium-ion battery recycling and engineered material company, by way of a subscription for Series C-1 preferred shares. As at December 31, 2023, the Company holds 806 series C-1 preferred shares of Ascend Elements with an estimated fair value of $ 8,582 (December 31, 2022 – $ 5,000 ). A gain on change in fair value of Ascend Elements at December 31, 2023 of $ 3,582 (2022 - $ nil ) determined based on the Company’s assessment of the fair value, was recognized in the Consolidated Statements of Comprehensive Loss. As Ascend Elements is a private company, there is no observable market data to use, so the Company’s assessment was determined based on a review of Ascend Elements’ business developments, financings and trends in the share prices of other companies in the same industry sector. The Company’s investment in Ascend Elements is classified as a Level 3 financial instrument (Note 24).

Property Plant and Equipment

Property Plant and Equipment	12 Months Ended
	Dec. 31, 2023
Disclosure of detailed information about property, plant and equipment [abstract]
Property Plant and Equipment	9. PROPERTY, PLANT AND EQUIPMENT Thacker 1 Equipment Right of Other Total $ $ $ $ $ Cost As at December 31, 2021 - 1,475 2,720 462 4,657 Additions - 1,265 658 239 2,162 As at December 31, 2022 - 2,740 3,378 701 6,819 Transfers from E&E (Note 10) 9,091 - - - 9,091 Additions 193,728 210 549 134 194,621 Disposals - - ( 275 ) ( 90 ) ( 365 ) As at December 31, 2023 202,819 2,950 3,652 745 210,166 Thacker 1 Equipment Right of Other Total $ $ $ $ $ Accumulated depreciation As at December 31, 2021 - 900 305 158 1,363 Depreciation for the year - 744 719 57 1,520 As at December 31, 2022 - 1,644 1,024 215 2,883 Depreciation for the year - 587 807 85 1,479 Disposals - - ( 188 ) ( 90 ) ( 278 ) As at December 31, 2023 - 2,231 1,643 210 4,084 Thacker 1 Equipment Right of Other Total $ $ $ $ $ Net book value As at December 31, 2021 - 575 2,415 304 3,294 As at December 31, 2022 - 1,096 2,354 486 3,936 As at December 31, 2023 202,819 719 2,009 535 206,082 1. The “Thacker Pass” category also includes right of use assets with a cost of $ 2,160 as at December 31, 2023. The Company has certain commitments for royalty and other payments to be made on Thacker Pass as set out below. These amounts will only be payable if the Company continues to hold the subject claims in the future and the royalties will only be incurred if the Company starts production from Thacker Pass. • 20 % royalty on revenue solely in respect of uranium; • 8 % gross revenue royalty on all claims up to a cumulative payment of $ 22,000 . The royalty will then be reduced to 4 % for the life of the project. The Company has the option at any time to reduce the royalty to 1.75 % upon payment of $ 22,000 . 9. PROPERTY, PLANT AND EQUIPMENT (continued) At December 31, 2023, the Company had a commitment to make a final milestone payment of $ 7,876 relating to the purchase of housing units for construction employees, that was due and paid on January 2, 2024. Prepayments of $ 15,315 related to the housing units received in 2024 and related transportation costs, as well as the non-current portion of project insurance for Thacker Pass are included in Other assets.

Exploration and Evaluation Asse

Exploration and Evaluation Assets	12 Months Ended
	Dec. 31, 2023
Exploration and evaluation assets [abstract]
Exploration and Evaluation Assets	10. EXPLORATION AND EVALUATION ASSETS Exploration and evaluation assets relating to Thacker Pass and other projects were as follows: Total $ Exploration and evaluation assets, as at December 31, 2021 5,747 Additions 4,120 Write off of non-Thacker Pass assets ( 353 ) Exploration and evaluation assets, as at December 31, 2022 9,514 Additions 347 Transfers to PP&E (Note 9) ( 9,091 ) Total exploration and evaluation assets, as at December 31, 2023 770 Upon commencement of development of Thacker Pass on February 1, 2023, the capitalized costs of Thacker Pass were transferred from exploration and evaluation assets to property, plant and equipment and Old LAC commenced capitalizing development costs. Concurrent with the transfer of the Thacker Pass assets from exploration and evaluation to property, plant and equipment, the Company completed an impairment test of Thacker Pass which compared the carrying value to the recoverable amount. The recoverable amount is the greater of the value in use and the fair value less disposal costs. The fair value less disposal costs was calculated using a discounted cash flow model with feasibility study economics. The significant assumptions that impacted the fair value included future lithium prices, capital cost estimates, operating cost estimates, estimated mineral reserves and resources, and the discount rate. Based on the result of the impairment test, management concluded that there was no impairment.

Agreements with General Motors

Agreements with General Motors	12 Months Ended
	Dec. 31, 2023
Equity [abstract]
Agreements With General Motors	11. AGREEMENTS WITH GENERAL MOTORS On January 30, 2023, LAC North America entered into an agreement with GM, pursuant to which GM agreed to make a $ 650,000 equity investment in two tranches. The proceeds from the Transaction are to be used for the construction and development of Thacker Pass. On February 16, 2023, the Tranche 1 Investment of $ 320,148 closed, resulting in GM’s purchase of 15,002 common shares of Old LAC which became an equivalent number of shares of the Company post-Separation. In connection with the Tranche 1 Investment, the Company and GM also entered into (a) a warrant certificate and a subscription agreement (the “ GM Tranche 2 Agreements ”), each in relation to a second tranche investment of up to $ 329,852 ; (b) the Offtake Agreement and (c) an investor rights agreement. 11. AGREEMENTS WITH GENERAL MOTORS (continued ) GM Tranche 2 Agreements Pursuant to the GM Tranche 2 Agreements, as the Separation was completed before the closing of the Tranche 2 Investment by GM, the GM Tranche 2 Agreements with Old LAC were made ineffective in consideration for the purchase of two common shares of Old LAC and, a new subscription agreement was executed by New LAC and GM. The terms of the New LAC subscription agreement substantially mirrors the subscription agreement previously executed by Old LAC, subject to the shares and price being adjusted by the New LAC relative value ratio, such that GM’s second tranche investment of up to $ 329,852 will be made in New LAC. Pursuant the Tranche 2 Investment agreement which expires in August 2024 , GM may purchase common shares of New LAC subject to the satisfaction of certain conditions precedent, including the condition that the Company secures sufficient funding to complete the development of Phase 1 for Thacker Pass (the “Funding Condition"). The subscription agreement calls for an aggregate purchase price of up to $ 329,852 , with the number of shares to be determined using a price equal to the lower of (a) the 5-day volume weighted average share price (which is determined as of the date the notice that the certain conditions have been met) and (b) $ 17.36 per share. The GM Tranche 2 Agreements are treated as a derivative because the GM Tranche 2 Agreements may result in the issuance of a variable number of shares for the fixed subscription price. The derivative was initially measured at fair value and subsequently carried at fair value through profit and loss. The Company recorded the GM Tranche 2 Agreements derivative on January 30, 2023, at an initial fair value of $ 33,194 and the net proceeds of Tranche 1 investment were recorded in Net former parent investment. Financial advisory fees of approximately $ 16,803 and other transaction costs of $ 174 were paid in connection with the closing of the first tranche. The $ 1,760 portion of the transaction costs related to the GM Tranche 2 Agreements derivative were expensed. Transactions costs of $ 15,217 attributable to the GM Tranche 1 proceeds were recorded in the Net former parent investment. Financial advisory fees of approximately $ 6,600 will become payable upon completion of the closing of the second tranche of GM’s investment. Changes in the value of the GM Tranche 2 Agreements are summarized below: $ GM derivative liability On initial recognition as at January 30, 2023 ( 33,194 ) Gain on change in fair value 32,846 As at December 31, 2023 ( 348 ) The fair value of the derivative as of January 30, 2023, was determined using Monte Carlo simulation, with the following Old LAC’s inputs: volatility of 58.34 %, share price of $ 21.99 , a risk-free rate of 4.77 %, and an expected dividend of 0 %. The fair value of the derivative as of December 31, 2023, was estimated with the following inputs: volatility of 71.26 %, share price of $ 6.40 , a risk-free rate of 5.54 %, and an expected dividend of 0 %. A gain on change in the fair value of the derivative for the period from issuance to December 31, 2023, of $ 32,846 was recognized in the Consolidated Statement of Comprehensive Loss. 11. AGREEMENTS WITH GENERAL MOTORS (continued ) Valuation of the derivative is sensitive to changes in the Company's share price and the assumed volatility of common shares. The gain on change in fair value of the GM derivative liability of $ 32.8 million was driven by underlying valuation assumptions. A reduction/increase of the Company's share price by 10 % would result in a corresponding reduction/increase of the derivative value by 17 % and 31 % respectively. Offtake Agreement As part of the Arrangement, the Offtake Agreement was assigned to New LAC. Pursuant to the Offtake Agreement, GM may purchase up to 100 % of Thacker Pass Phase 1 production at a price based on prevailing market rates. The term of the arrangement for Phase 1 production is ten years, subject to a five-year extension at GM’s option and other limited extensions. The Company has also granted GM a right of first offer on Thacker Pass Phase 2 production. The volume available under the Offtake Agreement is subject to the receipt of the Tranche 2 Investment and may be reduced proportionately in certain circumstances if GM’s remaining investment is less than $ 329,852 .

Leases and Other Liabilities

Leases and Other Liabilities	12 Months Ended
	Dec. 31, 2023
Miscellaneous liabilities [abstract]
Leases and Other Liabilities	12. LEASES AND OTHER LIABILITIES Leases December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Leases Office leases 1,199 1,614 1,743 Cars and equipment leases 69 4 12 Land lease 1,845 - - 3,113 1,618 1,755 Other liabilities Mining contractor liability 3,500 5,950 5,940 6,613 7,568 7,695 Leases for office space, cars and equipment have terms ranging from 2 to 5 years . The land lease for land near the city of Winnemucca has a term of 40 years from signing in November 2023. Other liabilities During Q2 2019, LAC North America entered into a mining design, consulting and mining operations agreement with a mining contractor for Thacker Pass which included a financing component. In accordance with the agreement, LAC North America received $ 3,500 from the mining contractor in seven consecutive equal quarterly installments, with $ 1,500 received in 2019 and $ 2,000 received in 2020. These amounts are included in the mining contractor liability balance. The Company will pay a success fee to the mining contractor of $ 4,675 upon achieving certain commercial mining milestones or repay the $ 3,500 advance without interest if such commercial mining milestones are not met.

Share Capital and Equity Compen

Share Capital and Equity Compensation	12 Months Ended
	Dec. 31, 2023
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Share Capital and Equity Compensation	13. SHARE CAPITAL AND EQUITY COMPENSATION Share Capital Authorized and Issued Upon incorporation on January 23, 2023, New LAC's authorized share capital was comprised of an unlimited number of common shares without par value and an unlimited number of preference shares without par value (the " Preference Shares "). On October 3, 2023, as part of the Arrangement, among other things: (i) each Old LAC shareholder exchanged its Old LAC common shares for Old LAC class A common shares and Old LAC preference shares; (ii) each Old LAC shareholder then transferred its Old LAC preference shares to New LAC in exchange for Common Shares; (iii) 1,000,000 Preference Shares were issued to Old LAC in exchange for the North American business assets contributed; (vi) all Preference Shares issued to Old LAC were redeemed by New LAC in consideration for an aggregate redemption amount, after which all such Preference Shares were cancelled; and (iii) the notice of articles and articles of New LAC (the " Articles ") were amended to, among other things, eliminate the Preference Shares from the authorized share capital of New LAC such that, following such amendment, New LAC is authorized to issue only an unlimited number of common shares. At December 31, 2023, 161,778 common shares were issued and outstanding. Equity Incentive Plan Prior to the Separation on October 3, 2023, Old LAC’s employees participated in Old LAC’s equity incentive plan in accordance with the policies of the TSX whereby, from time to time, at the discretion of the Old LAC’s board of directors, eligible directors, officers, employees and consultants were: (1) granted incentive stock options exercisable to purchase Old LAC common shares; and (2) awarded DSUs, RSUs and PSUs that, subject to a recipient’s deferral right in accordance with the Income Tax Act (Canada), convert automatically into Old LAC common shares upon vesting. The exercise price of each stock option was based on the fair market price of Old LAC common shares at the time of grant. Stock options were granted for a maximum term of five years . There were no stock options outstanding at October 3, 2023. In connection with the completion of the Separation, the Company adopted an equity incentive plan (the “ Equity Incentive Plan ”). The Equity Incentive Plan provides for the grant to eligible directors and employees of incentive stock options exercisable to purchase common shares, Company RSUs that convert automatically into common shares and Company PSUs that are subject to performance conditions and/or multipliers and designated as such in accordance with the Equity Incentive Plan that are settled for common shares. The Equity Incentive Plan also provides for the grant to eligible directors of Company DSUs which the directors are entitled to redeem for common shares following retirement or termination from the Board. The Company RSUs may vest immediately or one-third per year on each of the grant anniversary dates over a period of up to three years and Company PSUs generally vest after three years. 13. SHARE CAPITAL AND EQUITY COMPENSATION (continued) In connection with the Arrangement, holders of all awarded DSUs, RSUs and PSUs of Old LAC previously held (collectively, the "Old LAC Units") received, in lieu of such outstanding Old LAC Units, equivalent incentive securities of the Company and of Lithium Argentina. On October 3, 2023, the Company had 160,048 common shares issued and outstanding, and 225 DSUs, 2,171 RSUs and 1,037 PSUs were issued in connection with the Arrangement. Restricted Share Units Pursuant to the Arrangement, the holders of the Old LAC RSUs exchanged each Old LAC RSU for one New LAC RSU and 0.87 of a new Lithium Argentina RSU. New LAC RSUs issued to holders of Old LAC RSU who serve as a director, employee or consultant of Lithium Argentina rather than New LAC upon the Separation vested immediately on closing of the Separation, while RSUs issued to those who serve New LAC are subject to the vesting conditions of the original Old LAC awards. From the date of Separation on October 3, 2023 to December 31, 2023, the Company granted 670 RSUs to its employees and consultants. The total estimated fair value of the RSUs was $ 4,878 based on the market of the Company’s shares on the grant date. As at December 31, 2023, there was $ 4,642 of total unamortized compensation cost relating to unvested RSUs. During the year ended December 31, 2023, stock-based compensation expense related to RSUs of $ 3,462 was charged to operating expenses including $ 964 that relates to the period from January 1, 2023 to Separation on October 3, 2023 (2022 - $ 3,058 ; 2021 - $ 2,100 ) and $ 1,460 was capitalized to Thacker Pass project (2022 - $ nil ; 2021- $ nil ). A summary of changes to the number of outstanding RSUs is as follows: Number of RSUs RSUs issued on Separation 2,171 Converted into shares ( 1,191 ) Granted 670 Balance, RSUs outstanding as at December 31, 2023 1,650 Deferred Share Units Pursuant to the Arrangement, the holders of the Old DSUs exchanged each Old LAC DSU for one New LAC DSU and 0.87 of a new Lithium Argentina DSU. A summary of changes to the number of outstanding DSUs is as follows: Number of DSUs DSUs issued on Separation 225 Converted into common shares ( 130 ) Balance, DSUs outstanding as at December 31, 2023 95 13. SHARE CAPITAL AND EQUITY COMPENSATION (continued) Performance Share Units Pursuant to the Arrangement, the holders of the Old LAC PSUs exchanged each Old LAC PSU for one New LAC PSU and 0.87 of a new Lithium Argentina PSU. PSUs issued by New LAC in exchange for previously outstanding PSUs issued by Old LAC remain subject to the time-based vesting conditions of the original Old LAC PSUs and, upon the passage of the time-based vesting conditions, will be settled by the issuance of one common share, irrespective of the performance multiplier the Old LAC PSUs were previously subject to. Notwithstanding the foregoing, New LAC PSUs that replaced Old LAC PSUs that were fully vested and outstanding prior to the Separation were settled by New LAC, as applicable, in accordance with the performance multiplier applicable to the PSUs replaced. As at December 31, 2023, there was $ 2,174 (2022 – $ 206 ) of unamortized compensation costs relating to unvested PSUs. During the year ended December 31, 2023, stock-based compensation expense related to PSUs of $ 4,126 was charged to operating expenses including $ 1,140 that relates to the period from January 1, 2023 to Separation on October 3, 2023 (2022 - $ 979 ; 2021 - $ 1,166 ) and $ 256 was capitalized to Thacker Pass project (2022 - $ nil ; 2021 - $ nil ). A summary of changes to the number of outstanding PSUs is as follows: Number of PSUs PSUs issued on Separation 1,037 Converted into common shares ( 409 ) Balance, PSUs outstanding as at December 31, 2023 628

Earnings (Loss) Per Share

Earnings (Loss) Per Share	12 Months Ended
	Dec. 31, 2023
Earnings per share [abstract]
Earnings (Loss) Per Share	14. EARNINGS (LOSS) PER SHARE The weighted average number of common shares outstanding used in the calculation of both basic and diluted earnings per share was derived from common shares issued as of the Separation date of October 3, 2023, adjusted for transactions that occurred post the same Separation date. Loss per share for the years ended December 31, 2022 and 2021, which is presented on a “carve-out” basis has been calculated using the number of shares of New LAC that were issued and outstanding upon Separation on October 3, 2023.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2023
Related party transactions [abstract]
Related party transactions	15. RELATED PARTY TRANSACTIONS The Company entered into the following transactions with related parties: Transition Services Agreement Upon closing of the Arrangement, the Company and Lithium Argentina entered into a Transition Services Agreement whereby each company provides various accounting, technical and other services, including managing settlement of employee equity awards, to each other for a defined period of time. Compensation of Directors and Key Management The following presentation of the remuneration of directors and key management personnel of the Company recognizes that directors and key management differs for the periods before and after Separation. The amounts for the period prior to Separation and all comparative periods represent an allocation of the remuneration of those directors and key management personnel allocated to LAC North America prior to the Separation date of October 3, 2023. The amounts for the period post-Separation are the actual costs incurred by the Company for those directors and key management personnel for compensation earned at and incurred by the Company post October 3, 2023, including year-end bonuses relating to the full 2023 year. 2023 2022 2021 For the period January 1 to October 2, $ $ $ Salaries, bonuses, benefits and directors' fees included in the Consolidated Statements of Comprehensive Loss 1,499 1,303 901 Salaries, bonuses and benefits included in PP&E 242 - - Equity compensation 1,670 644 672 For the period October 3 to December 31, Salaries, bonuses, benefits and directors' fees included in the Consolidated Statements of Comprehensive Loss 2,481 2,557 509 Salaries, bonuses and benefits included in PP&E 576 - - Equity compensation 1,538 361 132 Total for the year ended December 31, 8,006 4,865 2,214 Amounts due to directors and key management are as follows: As at December 31, 2023 2022 2021 $ $ $ Total due to directors and key management 2,376 1,415 671

General and Administrative Expe

General and Administrative Expenses	12 Months Ended
	Dec. 31, 2023
Selling, general and administrative expense [abstract]
General and Administrative Expenses	16. GENERAL AND ADMINISTRATIVE EXPENSES The following table summarizes the Company’s general and administrative expenses, which represent the activity of LAC North America for the period January 1, 2023 to October 2, 2023 and actual expenses for the period October 3, 2023 to December 31, 2023: For the year ended December 31, 2023 2022 2021 $ $ $ Salaries, benefits and directors’ fees 7,973 3,485 2,108 Office and administration 3,788 1,619 1,157 Professional fees 2,525 3,426 1,205 Regulatory and filing fees 374 161 214 Travel 450 334 67 Investor relations 998 350 231 Depreciation 166 170 134 16,274 9,545 5,116

Exploration and Evaluation Expe

Exploration and Evaluation Expenditures	12 Months Ended
	Dec. 31, 2023
Disclosure of exploration and expenditures [abstract]
Exploration and Evaluation Expenditures	17. EXPLORATION AND EVALUATION EXPENDITURES The following table summarizes the Company’s exploration and evaluation expenditures: For the year ended December 31, 2023 2022 2021 $ $ $ Consulting and salaries 2,405 10,840 7,395 Engineering 782 27,928 23,009 Permitting and environmental 268 3,285 2,391 Field supplies and other 14 1,592 942 Depreciation 196 1,520 658 Drilling and geological expenses 98 2,110 1,718 3,763 47,275 36,113

Transactions Costs

Transactions Costs	12 Months Ended
	Dec. 31, 2023
Notes and other explanatory information [abstract]
Transactions Costs	18. TRANSACTIONS COSTS The following table summarizes the Company’s transactions costs: For the years ended December 31, 2023 2022 2021 $ $ $ Separation cost allocation 4,626 - - DOE Loan due diligence costs 3,138 - - General Motors investment 2,777 - - 10,541 - - Separation costs are allocations of legal and professional fees from the former parent relating to the planning for, execution and closing of the Arrangement. DOE Loan costs relate to due diligence costs to advance the DOE Loan. General Motors investment includes transaction costs related to the derivative liability component of the Tranche 2 Investment.

Finance Costs

Finance Costs	12 Months Ended
	Dec. 31, 2023
Finance Costs [abstract]
Finance Costs	19. FINANCE COSTS The following table summarizes the Company’s finance costs: For the year ended December 31, 2023 2022 2021 $ $ $ Accrued interest on loan from former parent 301 3,591 2,359 Other 47 448 292 348 4,039 2,651

Finance and Other Income

Finance and Other Income	12 Months Ended
	Dec. 31, 2023
Finance and other income [abstract]
Finance and Other Income	20. FINANCE AND OTHER INCOME (EXPENSES) The following table summarizes the Company’s finance and other income: For the year ended December 31, 2023 2022 2021 $ $ $ Interest earned on cash deposits 2,945 - - Other 78 ( 338 ) ( 2 ) 3,023 ( 338 ) ( 2 )

Segmented Information

Segmented Information	12 Months Ended
	Dec. 31, 2023
Disclosure of operating segments [abstract]
Segmented Information	21. SEGMENTED INFORMATION The Company operates in one operating segment and one geographical area. Thacker Pass was in the exploration and evaluation phase and was transferred to the development stage effective February 1, 2023. Substantially all the assets and the liabilities of the Company relate to Thacker Pass.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Major components of tax expense (income) [abstract]
Income Taxes	22. INCOME TAXES A reconciliation of income taxes at Canadian statutory rates with reported taxes is as follows: For the year ended December 31, 2023 2022 2021 $ $ $ Loss from operations before tax ( 3,934 ) ( 67,798 ) ( 47,148 ) Gain from discontinued operations 122 ( 3,934 ) ( 67,798 ) ( 47,026 ) Statutory tax rate 27 % 27 % 27 % Expected income tax recovery at statutory tax rate ( 1,062 ) ( 18,305 ) ( 12,697 ) Items not taxable for income tax purposes ( 6,172 ) - - Effect of lower tax rate in foreign jurisdiction 640 3,241 2,417 Change in unrecognized deferred tax assets and other 6,594 15,064 10,280 Tax expense - - - 22. INCOME TAXES (continued) The significant components of the Company's deferred tax assets and liabilities are as follows: December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Deferred tax assets: Tax loss carryforwards 47,537 40,196 30,695 Exploration and evaluation assets 3,507 3,602 1,173 Property, plant and equipment (including right-of-use assets) - 536 - Investment in Green Technology Metals 1,004 346 - Investment in Ascend Elements - - - Other 1,724 100 109 Deferred tax assets 53,772 44,780 31,977 Deferred tax liabilities: Capital assets ( 163 ) - - Thacker Pass assets ( 4,631 ) - - Investment in Ascend Elements ( 484 ) - - Equity compensation ( 5,722 ) ( 4,845 ) - Deferred tax liabilities ( 11,000 ) ( 4,845 ) - Unrecognized deferred tax assets 42,772 39,935 31,977 The Company has non-capital loss carry-forwards in Canada of $ 5,488 expiring in 2043 and in the U.S. of approximately $ 219,311 of which $ 38,756 expires between 2029 and 2037 and $ 180,555 have no fixed date of expiry. The non-capital loss carry-forwards are available to reduce taxable income in Canada and the US, respectively. The gross deductible temporary difference for which no benefit is recognized is $ 203,836 (2022 - $ 200,482 ). As at December 31, 2023 and 2022, no deferred tax assets are recognized as it is not probable that sufficient future taxable profits will be available to realize such assets. Prior to Separation on October 3, 2023, the Company's operating results were included in Old LAC's financial statements and in its, or its respective subsidiaries', tax returns. For the purposes of the reporting periods prior to Separation, the income tax amounts included in these financial statements have been calculated as if the Company had filed tax returns on a stand-alone basis separate from Old LAC. For the purposes of the December 31, 2023 reporting period, the tax computations up to Separation include the allocation of certain costs from Old LAC to the Company. The tax computations from Separation on October 3, 2023 to December 31, 2023 reflect each entity's legal results. 22. INCOME TAXES (continued) The Separation was implemented by way of an Arrangement pursuant to which there was an exchange of Old LAC common shares for Lithium Argentina common shares and New LAC common shares. The Arrangement is structured to be tax-free by complying with all of the requirements of the public company applicable rules in Section 55 of the Income Tax Act (Canada). The Arrangement also includes an agreement between the Company and Lithium Argentina for certain cross-indemnities against tax-specific claims and an agreement that includes certain covenants that, for a period of three years after Separation on October 3, 2023, may prohibit, except in certain circumstances, the Company and Lithium Argentina from taking or failing to take certain actions that could cause the Arrangement to be taxed in a manner that is inconsistent with the "butterfly" tax treatment.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	12 Months Ended
	Dec. 31, 2023
Notes and other explanatory information [abstract]
Supplemental Cash Flow Information	23. SUPPLEMENTAL CASH FLOW INFORMATION For the year ended December 31, 2023 2022 2021 $ $ $ Interest received on cash deposits 1,373 - - Interest paid 278 462 293

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2023
Disclosure of detailed information about financial instruments [abstract]
Financial Instruments	24. FINANCIAL INSTRUMENTS Financial instruments recorded at fair value on the Statements of Financial position and presented in fair value disclosures are classified using a fair value hierarchy that reflects the significance of the inputs used in making the measurements. The fair value hierarchy has the following levels: • Level 1 – Unadjusted quoted prices in active markets for identical assets or liabilities; • Level 2 – Inputs other than quoted prices that are observable for assets or liabilities, either directly or indirectly; and • Level 3 – Inputs for assets and liabilities that are not based on observable market data. The fair value hierarchy requires the use of observable market inputs whenever such inputs exist. A financial instrument is classified in the lowest level of the hierarchy for which a significant input has been considered in measuring fair value. Common shares and preferred shares acquired as part of the Green Technology Metals and Ascend Elements investments respectively, and the GM Tranche 2 Agreements derivative are measured at fair value on the Consolidated Statements of Financial Position on a recurring basis. Cash and cash equivalents, and receivables, are measured at amortized cost on the consolidated statement of financial position. As at December 31, 2023, the fair value of financial instruments measured at amortized cost approximates their carrying value. Green Technology Metals shares are classified at level 1 of the fair value hierarchy (see Note 7), the GM Tranche 2 Agreements derivative (see Note 11) is classified at level 2 of the fair value hierarchy and Ascend Elements preference shares are classified at level 3 of the fair value hierarchy (see Note 8). The Company manages risks to minimize potential losses. The main objective of the Company’s risk management process is to ensure that the risks are properly identified and that the capital base is adequate in relation to those risks. The principal risks which the Company’s financial instruments are described below. 24. FINANCIAL INSTRUMENTS (continued) Credit Risk Credit risk is the risk of loss associated with a counterparty’s inability to fulfill its payment obligations. Financial instruments that potentially subject the Company to a concentration of credit risk consist primarily of cash and cash equivalents and receivables. The Company’s maximum exposure to credit risk for cash and receivables is the amount disclosed in the Consolidated Statements of Financial Position. Exposure to credit loss is limited by placing cash and cash equivalents (including the Tranche 1 Investment proceeds) primarily with one major Canadian bank, invested in US treasury bills and other short-term investments issued by the Canadian government or Canadian chartered banks. Expected credit losses estimated to be de minimis. Liquidity Risk Liquidity risk is the risk that the Company will not be able to meet its financial obligations as they fall due. The Company’s approach to managing liquidity is to evaluate current and expected liquidity requirements under both normal and stressed conditions to estimate and maintain sufficient reserves of cash and cash equivalents to meet its liquidity requirements in the short and long term. The Company prepares annual budgets, which are regularly monitored and updated as considered necessary. As at December 31, 2023, the Company had a cash and cash equivalents of $ 195,516 to settle current liabilities of $ 24,563 . Current liabilities include the GM Tranche 2 Agreements derivative which will be settled in shares. The following table summarizes the contractual maturities of the Company’s financial liabilities on an undiscounted basis: Years ended December 31, 2024 2025 2026 2027 Total $ $ $ $ $ Accounts payable and accrued liabilities 23,361 - - - 23,361 Obligations under office leases¹ 884 565 712 - 2,161 Obligations under land leases¹ 69 70 73 3,822 4,034 Other obligations¹ 54 3,551 23 - 3,628 Total 24,368 4,186 808 3,822 33,184 1. Include principal and interest/finance charges. Foreign Currency Risk The Company’s functional currency is United States dollars (“USD”). The Company is exposed to foreign currency risk on expenditures incurred in Canadian dollars (“CAD”) which are primarily for corporate expenditures at the head office in Canada. As at December 31, 2023, the Company held $ 8.5 million in cash and cash equivalents denominated in CAD. Strengthening/(weakening) of a USD/CAD exchange rate by 10 % would have resulted in a foreign exchange (loss)/gain for the Company of $ 848 at December 31, 2023.

Capital Management

Capital Management	12 Months Ended
	Dec. 31, 2023
Capital management [abstract]
Capital Management	25. CAPITAL MANAGEMENT The Company’s objectives when managing capital are to safeguard the Company’s ability to continue as a going concern in order to pursue the development of its mineral properties and to maintain a flexible capital structure. The Company manages the capital structure and makes adjustments to it in light of changes in economic conditions and the risk characteristics of the underlying assets. In order to carry out the planned exploration and development of its projects and pay for administrative costs, the Company will spend its existing working capital, continue advancing the DOE Loan for which Conditional Commitment has been received, and raise additional amounts if available as needed. Management reviews its capital management approach on an ongoing basis and believes that this approach, given the relative size of the Company, is reasonable.

Discontinued Operation

Discontinued Operation	12 Months Ended
	Dec. 31, 2023
Disclosure of analysis of single amount of discontinued operations [abstract]
Discontinued Operation	26. DISCONTINUED OPERATION On January 13, 2021, Old LAC completed the sale of its organoclay property, plant and equipment for net proceeds of $ 4,034 . The results from operations for the organoclay business have been presented as discontinued operations in the Consolidated Statements of Comprehensive Loss and the Consolidated Statements of Cash Flows. Years ended December 31, 2023 2022 2021 $ $ $ ORGANOCLAY SALES - - 18 COST OF SALES - - ( 42 ) GROSS LOSS - - ( 24 ) EXPENSES General, administrative, and other - - ( 37 ) - - ( 37 ) Other income - - 25 Gain on sale of assets - - 158 NET INCOME FROM DISCONTINUED OPERATION - - 122 - - Net cash inflow from discontinued operation - - 3,523

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2023
Disclosure of non-adjusting events after reporting period [abstract]
Subsequent Event	27. SUBSEQUENT EVENT On March 12, 2024, the Company received a Conditional Commitment for a $ 2.26 billion DOE Loan for financing the construction of the processing facilities at Thacker Pass for Phase 1. While this Conditional Commitment represents a significant milestone and demonstrates the DOE’s intent to finance Thacker Pass, certain technical, legal and financial conditions, including negotiation of definitive financing documents, must be satisfied before funding of the DOE Loan. There can be no assurances as to the terms and conditions of the definitive financing documents or whether the financing will be finalized.

Summary of Material Accountin_2

Summary of Material Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Disclosure of summary of materials policies [abstract]
Principles of Consolidation	Principles of Consolidation These consolidated financial statements include the accounts of the Company and its corporate group of companies, consisting of (i) wholly-owned US subsidiaries Lithium Nevada, RheoMinerals Inc., and KV project LLC; and (ii) Canadian wholly-owned subsidiary 1339480 B.C. Ltd. All intercompany transactions and balances have been eliminated. Subsidiaries are all entities over which the Company has control. The Company controls an entity when the group is exposed to, or has rights to, variable returns from its involvement with the entity and has the ability to affect those returns through its power to direct the activities of the entity. Subsidiaries are fully consolidated from the date on which control is transferred to the Company. They are deconsolidated from the date that control ceases. Intercompany transactions, balances and unrealized gains on transactions between group companies are eliminated.
Foreign Currency Translation	Foreign Currency Translation Functional and Presentation Currency Items included in the financial statements of each of the entities are measured using the currency of the primary economic environment in which the entity operates (the functional currency). The consolidated financial statements are presented in US dollars. The functional currency of the Company, as well as all subsidiaries, is the US dollar. Transactions and Balances Foreign currency transactions are translated into the functional currency using the exchange rates at the dates of the transactions. Foreign exchange gains and losses resulting from the settlement of such transactions and from the translation of monetary assets and liabilities denominated in foreign currencies at year end exchange rates are generally recognized in profit or loss. Non-monetary items measured at historical cost continue to be carried at the exchange rate at the date of the transaction.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist of cash held with banks and highly liquid short-term investments which can be withdrawn at any time and are subject to an insignificant risk of changes in value.
Exploration and Evaluation Assets	Exploration and Evaluation Assets Exploration expenditures excluding acquisition costs and claim maintenance costs are expensed until the establishment of technical feasibility and commercial viability based on a combination of the following factors: • The extent to which mineral reserves or mineral resources as defined in National Instrument 43-101 (“ NI 43-101 ”) have been identified through a feasibility study or similar document; and, • The status of mining leases, environmental and mining permits. Costs incurred relating to the acquisition and claim maintenance of mineral properties, including option payments and annual fees to maintain the property in good standing, and exploration expenditures performed within the geologic formation of an existing brownfield mining project are capitalized and deferred by property until the project to which they relate is sold, abandoned, impaired, or placed into production. The Company assesses its exploration and evaluation assets for indications of impairment on each balance sheet date and when events and circumstances indicate a risk of impairment. A property is written down or written off when the Company determines that an impairment of value has occurred or when exploration results indicate that no further work is warranted. Exploration and evaluation assets are tested for impairment immediately prior to reclassification to mineral property development costs.
Property, Plant and Equipment	Property, Plant and Equipment On initial recognition, property, plant and equipment are valued at cost. Cost includes the purchase price and directly attributable cost of acquisition or construction required to bring the asset to the location and condition necessary to be capable of operating in the manner intended by the Company, including appropriate borrowing costs and foreign exchange losses or gains on borrowings and related cash used to construct qualifying assets as defined under IFRS. Capitalization of costs incurred ceases when the asset is capable of operating in the manner intended by management. The Company applies judgment in its assessment of when the asset is capable of operating in the manner intended by management. Property, plant and equipment are subsequently measured at cost less accumulated depreciation, less any accumulated impairment losses, with the exception of land which is not depreciated. When parts of an item of property, plant and equipment have different useful lives, they are accounted for as separate items or major components. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Property, plant and equipment that are currently in use are depreciated as follows: • Process testing facility equipment included in “Equipment and machinery” – straight-line basis over the estimated useful life of 10 years; • Right-of-use assets – depreciated over the shorter of the asset’s useful life and the lease term on a straight-line basis; and • Office equipment included in “Other” – declining balance method at 20 % annual rate. The assets’ residual values, useful lives and depreciation methods are reviewed and adjusted, if appropriate, at least annually. The gain or loss arising on the disposal of an item of property, plant and equipment is determined as the difference between the sale proceeds and the carrying amount of the asset and is recognized in profit and loss.
Impairment of Property, Plant and Equipment	Impairment of Property, Plant and Equipment Property, plant and equipment are assessed for impairment indicators at each reporting date or when an impairment indicator arises if not at a reporting date. If an impairment indicator is identified, an impairment assessment is carried out. If an impairment loss is identified, it is recognized for the amount by which the asset’s carrying amount exceeds its recoverable amount. The recoverable amount is the higher of an asset’s fair value less cost of disposal and value in use. Fair value is determined as the amount that would be obtained from the sale of the asset in an arm’s length transaction between knowledgeable and willing parties. In assessing value in use, the estimated future cash flows are discounted to their present value using a pre-tax discount rate that reflects current market assessments of the time value of money and the risks specific to the asset. For the purposes of assessing impairment, assets are grouped at the lowest levels for which there are separately identifiable cash flows (cash-generating units). These are typically individual mines or development projects. Where the factors which resulted in an impairment loss subsequently reverse, the carrying amount of the asset (or cash-generating unit) is increased to the revised estimate of its recoverable amount, but to an amount that does not exceed the carrying amount that would have been determined had no impairment loss been recognized for the asset (or cash-generating unit) in prior years. A reversal of an impairment loss is recognized immediately in profit or loss.
Leases	Leases At inception of a contract, the Company assesses whether a contract is, or contains, a lease. A contract is, or contains, a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company leases office space, equipment, vehicles and land. Lease contracts entered into by the Company are typically made for fixed periods of 2 to 5 years, with the exception of land leases which have a term of 40 years. Lease terms are negotiated on an individual basis and contain a wide range of different terms and conditions. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Leases are recognized as a right-of-use asset and a corresponding liability at the date at which the leased asset is available for use by the Company. Payments associated with short-term leases and leases of low-value assets are recognized on a straight-line basis as an expense in profit or loss. Short-term leases are leases with a lease term of 12 months or less.
Financial Instruments	Financial Instruments Financial assets and liabilities are recognized when the Company becomes a party to the contractual provisions of the instrument. On initial recognition, financial assets are classified as and measured at: amortized cost, fair value through profit or loss (“FVTPL”) or fair value through OCI according to their contractual cash flow characteristics and the business models under which they are held. The Company’s investments in equity investments are classified as FVTPL. Investments in equity instruments are held for strategic purposes and classified as long term. Financial assets are measured at amortized cost if they are held for the collection of contractual cash flows where those cash flows solely represent payments of principal and interest and; the Company’s intent is to hold these financial assets in order to collect contractual cash flows. Financial liabilities are measured at amortized cost unless they are required to be measured at FVTPL. Financial assets are derecognized when the rights to receive cash flows from the assets have expired or have been transferred and the Company has transferred substantially all risks and rewards of ownership. Derivative instruments Derivative instruments, including embedded derivatives in executory contracts or financial liability contracts, are classified as at FVTPL, and recorded on the balance sheet at fair value. Unrealized gains and losses on derivatives not designated in a hedging relationship are recorded as part of income (expense). Fair values for derivative instruments are determined using inputs based on market conditions existing at the balance sheet date or settlement date of the derivative. Derivatives embedded in non-derivative contracts are recognized separately unless they are closely related to the host contract. Impairment of financial assets The Company assesses on a forward-looking basis the expected credit losses associated with its financial assets carried at amortized cost. The impairment methodology applied depends on whether there has been a significant increase in credit risk. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued)
Provisions	Provisions Provisions are recognized when the Company has a present obligation, legal or constructive, as a result of a past event, it is probable that an outflow of resources embodying economic benefits will be required to settle the obligation and a reliable estimate can be made of the amount of the obligation. If the effect of the time value of money is material, provisions are determined by discounting the expected future cash flows at a pre-tax rate that reflects current market assessments of the time value of money and, where appropriate, the risks specific to the liability. Where discounting is used, the increase in the provision due to the passage of time is recognized as a finance cost. Close down and restoration costs include dismantling and demolition of infrastructure and the removal of residual materials and remediation of disturbed areas. Estimated close down and restoration costs are provided for in the accounting period when the obligation arising from the related disturbance occurs, based on the net present value of estimated future costs. The cost estimates are updated during the life of the operation to reflect known developments, such as revisions to cost estimates and to the estimated lives of the operations and are subject to formal reviews at regular intervals. The initial closure provision together with changes resulting from changes in estimated cash flows or discount rates are capitalized within capital assets. These costs are then depreciated over the lives of the asset to which they relate, typically using the units of production method. The amortization or unwinding of the discount applied in establishing the net present value of provisions is charged to the statement of comprehensive (loss)/income as a financing cost. Provision is made for the estimated present value of the costs of environmental cleanup obligations outstanding at the statement of financial position date.
Income Taxes	Income Taxes Income taxes are comprised of current and deferred tax. Income tax is recognized in profit or loss except to the extent that it relates to items recognized directly in equity. Current tax expense is the expected tax payable on taxable income for the year, using tax rates enacted or substantively enacted at period-end, adjusted for amendments to tax payable with regards to previous years. Deferred tax is recorded using the liability method, providing for temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for taxation purposes. Temporary differences are not provided for the initial recognition of assets or liabilities that affect neither accounting or taxable loss, unless arising in a business combination, nor for differences relating to investments in subsidiaries to the extent that they are not probable to reverse in the foreseeable future. The amount of deferred tax provided is based on the expected manner of realization or settlement of the carrying amount of assets and liabilities, using tax rates enacted or substantively enacted at the statement of financial position date. A deferred tax asset is recognized only to the extent that it is probable that future taxable profits will be available against which the asset can be utilized. To the extent that the Company does not consider it probable that a deferred tax asset will be recovered, the deferred tax asset is not recorded.
Share Capital	Share Capital Common shares are classified as equity. Incremental costs directly attributable to the issuance of shares are recognized as a deduction from equity.
Earnings/(Loss) per Share	Earnings/(Loss) per Share Basic earnings/(loss) per share is computed by dividing the net earnings or loss attributable to shareholders of the Company by the weighted average number of common shares outstanding during the reporting period. For periods presented on a "carve-out" basis, the number of shares issued and outstanding upon Separation is used as the denominator in the calculation of basic earnings/(loss) per share. The diluted earnings/(loss) per share calculation is based on the weighted average number of common shares outstanding during the period, plus the effects of dilutive common share equivalents. This method requires that the dilutive effect of outstanding options and warrants issued should be calculated using the treasury stock method. This method assumes that all common share equivalents have been exercised at the beginning of the period (or at the time of issuance, if later), and that the funds obtained thereby were used to purchase common shares of the Company at the average trading price of the common shares during the period, but only if dilutive.
Equity-Based Compensation	Equity-Based Compensation The Company’s equity incentive plan allows the grant of stock options, restricted share units ("RSUs"), performance share units (PSUs") and deferred share units ("DSUs"). The cost of equity-settled payment arrangements is recorded based on the estimated fair value at the grant date and charged to earnings over the vesting period. Each tranche in an award is considered a separate award with its own vesting period and grant date fair value. The fair value of each tranche is measured at the date of grant using Monte Carlo simulation methodology for performance share units. Compensation expense is recognized over the tranche’s vesting period based on the number of awards expected to vest, by increasing contributed surplus. The number of awards expected to vest is reviewed at least annually with any impact being recognized immediately. Where equity instruments are granted to non-employees, they are recorded at the fair value of the goods or services received in the statement of comprehensive (loss)/income, unless they are related to the issuance of equity instruments. Amounts related to the issuance of shares are recorded as a reduction of share capital. When the value of goods or services received in exchange for the share-based payment cannot be reliably estimated, the fair value is measured by use of a valuation model.
Estimation Uncertainty and Significant Accounting Policy Judgments	Estimation Uncertainty and Significant Accounting Policy Judgments The preparation of these consolidated financial statements require management to make assumptions, estimates, and judgments that affect the amounts reported in these financial statements and accompanying notes. The Company bases its estimates on historical experience and various assumptions that are believed to be reasonable at the time the estimate was made. Accordingly, actual results may differ from amounts estimated in these consolidated financial statements and such differences could be material. Significant accounting policy judgments in the preparation of the Company's financial statements are as follows: Accounting for the Agreements with General Motors The Company’s accounting for the agreements with General Motors involved judgment, specifically in its assumption that in determination the Offtake Agreement represents an agreement with market selling prices; and that the Offtake is separate from the equity financing provided by GM (see Note 11). The second tranche investment component of subscription agreements with GM which involved estimation of fair value, utilizes a Monte Carlo simulation that required significant assumptions, including expected volatility of Old LAC’s (and, following Separation, New LAC’s) share price, an estimated risk-free rate and an estimated dividend. Commencement of Development of Thacker Pass The Company determined that the technical feasibility and commercial viability of Thacker Pass had been demonstrated following the release of an independent National Instrument 43-101 feasibility study (the “ Thacker Pass Feasibility Study ”) on January 31, 2023, the receipt of the favorable ruling from the U.S. District Court, District of Nevada (“U.S. District Court ”) for the issuance of the Record of Decision (“ ROD ”), and the receipt of notice to proceed from the Bureau of Land Management (“ BLM ”) on February 7, 2023. The Company entered into an engineering, procurement and construction management agreement and other construction-related contracts. Construction of Thacker Pass, including site preparation, geotechnical drilling, water pipeline development and associated infrastructure commenced. Accordingly, the capitalized costs of Thacker Pass were transferred to property, plant and equipment from exploration and evaluation assets and capitalization of development costs commenced February 1, 2023. Concurrent with the transfer of the Thacker Pass assets from exploration and evaluation to property, plant and equipment, the Company completed an impairment test of Thacker Pass which compared the carrying value to the recoverable amount. The recoverable amount is the greater of the value in use and the fair value less disposal costs. The fair value less disposal costs is calculated using a discounted cash flow model with feasibility study economics. The significant assumptions that impacted the fair value included future lithium prices, capital cost estimates, operating cost estimates, estimated mineral reserves and resources, and the discount rate. Management applied judgment in conducting the impairment test and concluded that there was no impairment. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Assessment of Impairment of Thacker Pass The Company applied judgment in carrying out an evaluation of Thacker Pass for indicators of impairment at December 31, 2023. The Company carried out the evaluation considering internal and external factors including but not limited to, the Thacker Pass November 2022 Feasibility Study including assumptions and sensitivity analysis, market trends in lithium prices, discount rates, trends in financial markets and the Company's market capitalization.
New IFRS Pronouncements	New IFRS Pronouncements Amendments to IAS 1 – Presentation of Financial Statements In October 2022, the IASB issued amendments to IAS 1, Presentation of Financial Statements titled Non-current Liabilities with Covenants. These amendments sought to improve the information that an entity provides when its right to defer settlement of a liability is subject to compliance with covenants within 12 months after the reporting period. These amendments to IAS 1 override but incorporate the previous amendments, Classification of liabilities as current or non-current, issued in January 2020, which clarified that liabilities are classified as either current or non-current, depending on the rights that exist at the end of the reporting period. Liabilities should be classified as non-current if a company has a substantive right to defer settlement for at least 12 months at the end of the reporting period. The amendments are effective January 1, 2024, with early adoption permitted. Retrospective application is required on adoption. These amendments are not expected to have a material effect on the financial statements of the Company. Amendment to IAS 1 and IFRS Practice Statement 2 – Disclosure of Accounting Policies In February 2021, the IASB issued amendments to IAS 1, “Presentation of Financial Statements” and the IFRS Practice Statement 2 “Making Materiality Judgments” to provide guidance on the application of materiality judgments to accounting policy disclosures. The amendments to IAS 1 replace the requirement to disclose significant accounting policies with a requirement to disclose material accounting policies. Guidance and illustrative examples are added in the Practice Statement to assist in the application of the materiality concept when making judgments about accounting policy disclosures. The amendments were effective January 1, 2023. These amendments did not impact these consolidated financial statements. 4. SUMMARY OF MATERIAL ACCOUNTING POLICIES (continued) Amendments to IAS 12 – International Tax Reform Pillar Two Model Rules In May 2023, the IASB issued amendments to IAS 12, International Tax Reform - Pillar Two Model Rules to clarify the application of IAS 12 Income Taxes to income taxes arising from tax law enacted or substantively enacted to implement the Organization for Economic Co-operation and Development (OECD)/G20 Inclusive Framework on Base Erosion and Profit Shifting (BEPS) Pillar Two model rules (Pillar Two income taxes). The amendments introduce a mandatory temporary exception to the accounting for deferred taxes arising from the jurisdictional implementation of the Pillar Two model rules and disclosure requirements for the entities to help users of the financial statements better understand an entity’s exposure to Pillar Two income taxes arising from that legislation, particularly before its effective date. The mandatory temporary exception, the use of which is required to be disclosed, applies immediately. The remaining disclosure requirements apply for annual reporting periods beginning on or after January 1, 2023, but not for any interim periods ending on or before December 31, 2023. These amendments did not impact these consolidated financial statements.

Reorganization (Tables)

Reorganization (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of reorganization [abstract]
Summary of Share Transactions Pursuant to the Arrangement	Share transactions pursuant to the Arrangement are as follows: $ Cash transferred to establish sufficient working capital pursuant to the Arrangement 75,000 Loan from former parent contributed pursuant to the Arrangement 46,258 Share issuance costs pursuant to the Arrangement ( 7,479 ) 113,779

Cash and Cash Equivalents (Tabl

Cash and Cash Equivalents (Tables)	12 Months Ended
	Dec. 31, 2023
Cash and cash equivalents [abstract]
Summary of Cash and Cash Equivalents	December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Cash 12,050 636 933 Cash equivalents 183,466 - - 195,516 636 933

Receivables, Prepaids and Dep_2

Receivables, Prepaids and Deposits (Tables)	12 Months Ended
	Dec. 31, 2023
Prepaids, deposits and receivables [abstract]
Summary of Receivables, Prepaids and Deposits	December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Prepaids and deposits 5,872 1,298 754 Receivables 2,922 3 124 Interest receivable 1,573 - - 10,367 1,301 878

Property Plant and Equipment (T

Property Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of detailed information about property, plant and equipment [abstract]
Summary of Property, Plant and Equipment	Thacker 1 Equipment Right of Other Total $ $ $ $ $ Cost As at December 31, 2021 - 1,475 2,720 462 4,657 Additions - 1,265 658 239 2,162 As at December 31, 2022 - 2,740 3,378 701 6,819 Transfers from E&E (Note 10) 9,091 - - - 9,091 Additions 193,728 210 549 134 194,621 Disposals - - ( 275 ) ( 90 ) ( 365 ) As at December 31, 2023 202,819 2,950 3,652 745 210,166 Thacker 1 Equipment Right of Other Total $ $ $ $ $ Accumulated depreciation As at December 31, 2021 - 900 305 158 1,363 Depreciation for the year - 744 719 57 1,520 As at December 31, 2022 - 1,644 1,024 215 2,883 Depreciation for the year - 587 807 85 1,479 Disposals - - ( 188 ) ( 90 ) ( 278 ) As at December 31, 2023 - 2,231 1,643 210 4,084 Thacker 1 Equipment Right of Other Total $ $ $ $ $ Net book value As at December 31, 2021 - 575 2,415 304 3,294 As at December 31, 2022 - 1,096 2,354 486 3,936 As at December 31, 2023 202,819 719 2,009 535 206,082 1. The “Thacker Pass” category also includes right of use assets with a cost of $ 2,160 as at December 31, 2023.

Exploration and Evaluation As_2

Exploration and Evaluation Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Exploration and evaluation assets [abstract]
Schedule of Exploration and Evaluation Assets Relating to Thacker Pass Project	Exploration and evaluation assets relating to Thacker Pass and other projects were as follows: Total $ Exploration and evaluation assets, as at December 31, 2021 5,747 Additions 4,120 Write off of non-Thacker Pass assets ( 353 ) Exploration and evaluation assets, as at December 31, 2022 9,514 Additions 347 Transfers to PP&E (Note 9) ( 9,091 ) Total exploration and evaluation assets, as at December 31, 2023 770

Agreements With General Motors

Agreements With General Motors (Tables)	12 Months Ended
	Dec. 31, 2023
Equity [abstract]
Schedule of Change in the Value of Derivative Agreement	Changes in the value of the GM Tranche 2 Agreements are summarized below: $ GM derivative liability On initial recognition as at January 30, 2023 ( 33,194 ) Gain on change in fair value 32,846 As at December 31, 2023 ( 348 )

Leases and Other Liabilities (T

Leases and Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Miscellaneous liabilities [abstract]
Summary of Leases and Other Liabilities	December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Leases Office leases 1,199 1,614 1,743 Cars and equipment leases 69 4 12 Land lease 1,845 - - 3,113 1,618 1,755 Other liabilities Mining contractor liability 3,500 5,950 5,940 6,613 7,568 7,695

Share Capital and Equity Comp_2

Share Capital and Equity Compensation (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of terms and conditions of share-based payment arrangement [abstract]
Summary of Changes to Number of Restricted Shares	A summary of changes to the number of outstanding RSUs is as follows: Number of RSUs RSUs issued on Separation 2,171 Converted into shares ( 1,191 ) Granted 670 Balance, RSUs outstanding as at December 31, 2023 1,650
Summary of Changes to Number of Deferred Share Units	A summary of changes to the number of outstanding DSUs is as follows: Number of DSUs DSUs issued on Separation 225 Converted into common shares ( 130 ) Balance, DSUs outstanding as at December 31, 2023 95
Summary of Changes to Number of Performance Share Units	A summary of changes to the number of outstanding PSUs is as follows: Number of PSUs PSUs issued on Separation 1,037 Converted into common shares ( 409 ) Balance, PSUs outstanding as at December 31, 2023 628

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2023
Related party transactions [abstract]
Summary of Compensation of Directors and Key Management	The following presentation of the remuneration of directors and key management personnel of the Company recognizes that directors and key management differs for the periods before and after Separation. 2023 2022 2021 For the period January 1 to October 2, $ $ $ Salaries, bonuses, benefits and directors' fees included in the Consolidated Statements of Comprehensive Loss 1,499 1,303 901 Salaries, bonuses and benefits included in PP&E 242 - - Equity compensation 1,670 644 672 For the period October 3 to December 31, Salaries, bonuses, benefits and directors' fees included in the Consolidated Statements of Comprehensive Loss 2,481 2,557 509 Salaries, bonuses and benefits included in PP&E 576 - - Equity compensation 1,538 361 132 Total for the year ended December 31, 8,006 4,865 2,214 Amounts due to directors and key management are as follows: As at December 31, 2023 2022 2021 $ $ $ Total due to directors and key management 2,376 1,415 671

General and Administrative Ex_2

General and Administrative Expenses (Tables)	12 Months Ended
	Dec. 31, 2023
Selling, general and administrative expense [abstract]
Summary of Company's General and Administrative Expenses	The following table summarizes the Company’s general and administrative expenses, which represent the activity of LAC North America for the period January 1, 2023 to October 2, 2023 and actual expenses for the period October 3, 2023 to December 31, 2023: For the year ended December 31, 2023 2022 2021 $ $ $ Salaries, benefits and directors’ fees 7,973 3,485 2,108 Office and administration 3,788 1,619 1,157 Professional fees 2,525 3,426 1,205 Regulatory and filing fees 374 161 214 Travel 450 334 67 Investor relations 998 350 231 Depreciation 166 170 134 16,274 9,545 5,116

Exploration and Evaluation Ex_2

Exploration and Evaluation Expenditures (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of exploration and expenditures [abstract]
Summary of Company's Exploration and Evaluation Expenditures	The following table summarizes the Company’s exploration and evaluation expenditures: For the year ended December 31, 2023 2022 2021 $ $ $ Consulting and salaries 2,405 10,840 7,395 Engineering 782 27,928 23,009 Permitting and environmental 268 3,285 2,391 Field supplies and other 14 1,592 942 Depreciation 196 1,520 658 Drilling and geological expenses 98 2,110 1,718 3,763 47,275 36,113

Transactions Costs (Tables)

Transactions Costs (Tables)	12 Months Ended
	Dec. 31, 2023
Notes and other explanatory information [abstract]
Summary Of Transactions Costs	The following table summarizes the Company’s transactions costs: For the years ended December 31, 2023 2022 2021 $ $ $ Separation cost allocation 4,626 - - DOE Loan due diligence costs 3,138 - - General Motors investment 2,777 - - 10,541 - -

Finance Costs (Tables)

Finance Costs (Tables)	12 Months Ended
	Dec. 31, 2023
Finance Costs [abstract]
Summarizes the Company's Finance Costs	The following table summarizes the Company’s finance costs: For the year ended December 31, 2023 2022 2021 $ $ $ Accrued interest on loan from former parent 301 3,591 2,359 Other 47 448 292 348 4,039 2,651

Finance and Other Income (Table

Finance and Other Income (Tables)	12 Months Ended
	Dec. 31, 2023
Finance and other income [abstract]
Summary of Finance and Other Income	The following table summarizes the Company’s finance and other income: For the year ended December 31, 2023 2022 2021 $ $ $ Interest earned on cash deposits 2,945 - - Other 78 ( 338 ) ( 2 ) 3,023 ( 338 ) ( 2 )

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Major components of tax expense (income) [abstract]
Summary of Reconciliation of Income Taxes at Canadian Statutory Rates with Reported Taxes	A reconciliation of income taxes at Canadian statutory rates with reported taxes is as follows: For the year ended December 31, 2023 2022 2021 $ $ $ Loss from operations before tax ( 3,934 ) ( 67,798 ) ( 47,148 ) Gain from discontinued operations 122 ( 3,934 ) ( 67,798 ) ( 47,026 ) Statutory tax rate 27 % 27 % 27 % Expected income tax recovery at statutory tax rate ( 1,062 ) ( 18,305 ) ( 12,697 ) Items not taxable for income tax purposes ( 6,172 ) - - Effect of lower tax rate in foreign jurisdiction 640 3,241 2,417 Change in unrecognized deferred tax assets and other 6,594 15,064 10,280 Tax expense - - -
Summary of Significant Components of Deferred Tax Assets and Liabilities	The significant components of the Company's deferred tax assets and liabilities are as follows: December 31, 2023 December 31, 2022 December 31, 2021 $ $ $ Deferred tax assets: Tax loss carryforwards 47,537 40,196 30,695 Exploration and evaluation assets 3,507 3,602 1,173 Property, plant and equipment (including right-of-use assets) - 536 - Investment in Green Technology Metals 1,004 346 - Investment in Ascend Elements - - - Other 1,724 100 109 Deferred tax assets 53,772 44,780 31,977 Deferred tax liabilities: Capital assets ( 163 ) - - Thacker Pass assets ( 4,631 ) - - Investment in Ascend Elements ( 484 ) - - Equity compensation ( 5,722 ) ( 4,845 ) - Deferred tax liabilities ( 11,000 ) ( 4,845 ) - Unrecognized deferred tax assets 42,772 39,935 31,977

Supplemental Cash Flow Inform_2

Supplemental Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2023
Notes and other explanatory information [abstract]
Schedule of Supplemental Cash Flow Information	For the year ended December 31, 2023 2022 2021 $ $ $ Interest received on cash deposits 1,373 - - Interest paid 278 462 293

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of detailed information about financial instruments [abstract]
Summary of the contractual maturities of the Company's financial liabilities	The following table summarizes the contractual maturities of the Company’s financial liabilities on an undiscounted basis: Years ended December 31, 2024 2025 2026 2027 Total $ $ $ $ $ Accounts payable and accrued liabilities 23,361 - - - 23,361 Obligations under office leases¹ 884 565 712 - 2,161 Obligations under land leases¹ 69 70 73 3,822 4,034 Other obligations¹ 54 3,551 23 - 3,628 Total 24,368 4,186 808 3,822 33,184

Discontinued Operation (Tables)

Discontinued Operation (Tables)	12 Months Ended
	Dec. 31, 2023
Disclosure of analysis of single amount of discontinued operations [abstract]
Schedule of Discontinued Operation	Years ended December 31, 2023 2022 2021 $ $ $ ORGANOCLAY SALES - - 18 COST OF SALES - - ( 42 ) GROSS LOSS - - ( 24 ) EXPENSES General, administrative, and other - - ( 37 ) - - ( 37 ) Other income - - 25 Gain on sale of assets - - 158 NET INCOME FROM DISCONTINUED OPERATION - - 122 - - Net cash inflow from discontinued operation - - 3,523

Background and Nature of Oper_2

Background and Nature of Operations - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Mar. 12, 2024	Jan. 30, 2023
Disclosure of detailed information about investment property [line items]
Name of reporting entity	Lithium Americas Corp.
Ownership interest in subsidiary	100%
Subsequent events [member]
Disclosure of detailed information about investment property [line items]
Conditional commitment		$ 2,260
General Motors Holdings LLC [member]
Disclosure of detailed information about investment property [line items]
Payment for investment			$ 650
U S Department of Energy [Member] | Subsequent events [member]
Disclosure of detailed information about investment property [line items]
Conditional commitment		$ 2,260
Common shares [member] | General Motors Holdings LLC [member]
Disclosure of detailed information about investment property [line items]
Number of aggregate subscription receipts from investment			15,002
Tranche 1 investment [member] | General Motors Holdings LLC [member]
Disclosure of detailed information about investment property [line items]
Payment for investment			$ 320.1
Tranche 2 Investment | General Motors Holdings LLC [member]
Disclosure of detailed information about investment property [line items]
Payment for investment			$ 329.9

Reorganization - Additional Inf

Reorganization - Additional Information (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CAD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Disclosure of detailed information about investment property [line items]
Accrued interest	$ 43,600
Cash	195,516	$ 8.5	$ 636	$ 933	$ 512
Working capital balance	75,000
GM Tranche 1 Investment [member]
Disclosure of detailed information about investment property [line items]
Cash	$ 275,500

Reorganization - Summary of Sha

Reorganization - Summary of Share Transactions Pursuant to the Arrangement (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Disclosure of reorganization [abstract]
Cash transferred to establish sufficient working capital pursuant to the Arrangement	$ 75,000
Loan from former parent contributed pursuant to the Arrangement	46,258
Share issuance costs pursuant to the Arrangement	(7,479)
Outstanding commitments made by entity, related party transactions, total	$ 113,779

Summary of Material Accountin_3

Summary of Material Accounting Policies - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023
Summary of material accounting policies [line items]
Land leases term	40 years
Bottom of range [member]
Summary of material accounting policies [line items]
Lease contracts term	2 years
Top of range [member]
Summary of material accounting policies [line items]
Lease contracts term	5 years
Process testing facility equipment [member]
Summary of material accounting policies [line items]
Property, plant and equipment, depreciation method	straight-line basis
Property plant and equipment, estimated useful life	10 years
Office equipment [member]
Summary of material accounting policies [line items]
Property, plant and equipment, depreciation method	declining balance method
Property plant and equipment annual depreciation rate	20%

Cash and Cash Equivalents - Sum

Cash and Cash Equivalents - Summary of Cash and Cash Equivalents (Details) $ in Thousands, $ in Millions	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CAD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Cash and cash equivalents [abstract]
Cash	$ 12,050		$ 636	$ 933
Cash equivalents	183,466		0	0
Cash and cash equivalents as presented in the Statement of Financial Position	195,516	$ 8.5	636	933	$ 512
Restricted cash	$ 288		$ 0	$ 0

Cash and Cash Equivalents - Add

Cash and Cash Equivalents - Additional Information (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CAD ($)	Oct. 03, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 CAD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Disclosure of financial assets [line items]
Cash and cash equivalents	$ 195,516	$ 8.5		$ 636		$ 933	$ 512
Canadian dollars [member]
Disclosure of financial assets [line items]
Cash and cash equivalents		$ 8.5			$ 0
US dollars [member]
Disclosure of financial assets [line items]
Cash and cash equivalents	$ 187,000			$ 600
Bottom of range [member]
Disclosure of financial assets [line items]
Interest earned	3%
Top of range [member]
Disclosure of financial assets [line items]
Interest earned	5.50%
Tranche 1 investment [member]
Disclosure of financial assets [line items]
Cash and cash equivalents			$ 75,000

Receivables, Prepaids and Dep_3

Receivables, Prepaids and Deposits - Summary of Receivables, Prepaids and Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Prepaids, deposits and receivables [abstract]
Prepaids and deposits	$ 5,872	$ 1,298	$ 754
Receivables	2,922	3	124
Interest receivable	1,573	0	0
Prepaid and deposits and receivables	$ 10,367	$ 1,301	$ 878

Investment in Green Technolog_2

Investment in Green Technology Metals - Additional Information (Details) - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
	Apr. 28, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of interest in other entities [line items]
Investment in Green Technology Metals		$ 2,580	$ 7,451	$ 0
Green technology metals [member]
Disclosure of interest in other entities [line items]
Payment to acquire investments other than equity investments	$ 10,000
Investment owned number of shares		13,301
Percentage of equity interests acquired		4%
Investment in Green Technology Metals		$ 2,580	7,451
Gains losses recognized in profit or loss fair value measurement assets		$ 4,871	$ 2,564

Investment in Ascend Elements -

Investment in Ascend Elements - Additional Information (Details) - USD ($) shares in Thousands, $ in Thousands		12 Months Ended
	Jul. 18, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of joint operations [line items]
Payment to acquire investments in preferred shares		$ 0	$ 5,000	$ 0
Investment in Ascend Elements		8,582	5,000	$ 0
Gain on change in fair value		$ 32,846
Ascend Elements, Inc [member]
Disclosure of joint operations [line items]
Payment to acquire investments in preferred shares	$ 5,000
Investment owned number of shares		806
Investment in Ascend Elements		$ 8,582	5,000
Gain on change in fair value		$ 3,582	$ 0

Property, Plant and Equipment -

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of detailed information about property, plant and equipment [line items]
Cost of property plant and equipment, beginning of period	$ 6,819	$ 4,657
Accumulated depreciation of property plant and equipment, beginning of period	2,883	1,363
Transfers from E&E (Note 10)	9,091
Additions	194,621	2,162
Disposals	(365)
Depreciation for the year	1,479	1,520
Disposals	(278)
Cost of property plant and equipment, end of period	210,166	6,819
Accumulated depreciation of property plant and equipment, end of period	4,084	2,883
Total property, plant and equipment	206,082	3,936	$ 3,294
Right-of-use assets [member]
Disclosure of detailed information about property, plant and equipment [line items]
Cost of property plant and equipment, beginning of period	3,378	2,720
Accumulated depreciation of property plant and equipment, beginning of period	1,024	305
Additions	549	658
Disposals	(275)
Depreciation for the year	807	719
Disposals	(188)
Cost of property plant and equipment, end of period	3,652	3,378
Accumulated depreciation of property plant and equipment, end of period	1,643	1,024
Total property, plant and equipment	2,009	2,354	2,415
Thacker Pass Project [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Transfers from E&E (Note 10)	(9,091)
Additions	193,728
Cost of property plant and equipment, end of period	202,819
Total property, plant and equipment	202,819
Equipment and machinery [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Cost of property plant and equipment, beginning of period	2,740	1,475
Accumulated depreciation of property plant and equipment, beginning of period	1,644	900
Additions	210	1,265
Depreciation for the year	587	744
Cost of property plant and equipment, end of period	2,950	2,740
Accumulated depreciation of property plant and equipment, end of period	2,231	1,644
Total property, plant and equipment	719	1,096	575
Other [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Cost of property plant and equipment, beginning of period	701	462
Accumulated depreciation of property plant and equipment, beginning of period	215	158
Additions	134	239
Disposals	(90)
Depreciation for the year	85	57
Disposals	(90)
Cost of property plant and equipment, end of period	745	701
Accumulated depreciation of property plant and equipment, end of period	210	215
Total property, plant and equipment	$ 535	$ 486	$ 304

Property, Plant and Equipment_2

Property, Plant and Equipment - Summary of Property, Plant and Equipment (Parenthetical) (Details) $ in Thousands	Dec. 31, 2023 USD ($)
Thacker Pass [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Right of use assets	$ 2,160

Property, Plant and Equipment_3

Property, Plant and Equipment - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Uranium [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Royalty payable on revenue percentage	20%
Thacker Pass [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Prepayments on housing units	$ 15,315
Royalty Claims [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Capital commitments	$ 22,000
Royalty payable on revenue percentage	8%
Royalty payable on revenue for life of project percentage	4%
Royalty payable on revenue upon payment of commitment percentage	1.75%
Purchase Of Housing Units [Member]
Disclosure of detailed information about property, plant and equipment [line items]
Contractual capital commitments	$ 7,876

Exploration and Evaluation As_3

Exploration and Evaluation Assets - Schedule of Exploration and Evaluation Assets Relating to Thacker Pass Project (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Exploration and evaluation assets [abstract]
Beginning balance	$ 9,514	$ 5,747
Additions	347	4,120
Write off of non-Thacker Pass assets		(353)
Transfers to PP&E (Note 9)	(9,091)
Ending balance	$ 770	$ 9,514

Agreements with General Motor_2

Agreements with General Motors - Additional information (Details) $ / shares in Units, shares in Thousands, $ in Thousands			12 Months Ended
	Feb. 16, 2023 USD ($) shares	Jan. 30, 2023 USD ($) $ / shares	Dec. 31, 2023 USD ($) Tranche $ / shares	Dec. 31, 2022 USD ($)
Initial fair value of derivative			$ (348)	$ (33,194)
Tranche One [Member]
Issue of equity	$ 320,148
Number of shares issued | shares	15,002
Professional fees		$ 16,803
Other Transaction Cost		174
Tranche Two [Member]
Equity Investment From Investor		$ 329,852
Number of Tranche | Tranche			2
Investment Agreement Expiration Date			2024-08
Purchase price per share | $ / shares		$ 17.36
Initial fair value of derivative		$ 33,194
Professional fees		6,600
Transaction cost related to derivative expense		1,760
Transaction cost related to former parent investment		15,217
Volatility rate			71.26%
Share price | $ / shares			$ 6.4
Risk free rate			5.54%
Expected dividend rate			0%
Investments accounted for using equity method		$ 650,000
Acquisition percentage			100%
Gain loss of change in fair value of derivative			$ 32,846
Top of range [member] | Tranche Two [Member]
Investments accounted for using equity method			$ 329,852
Old lac [member] | Tranche Two [Member]
Volatility rate		58.34%
Share price | $ / shares		$ 21.99
Risk free rate		4.77%
Expected dividend rate		0%
share price [member] | Tranche Two [Member]
Change in percentage			10%
share price [member] | Top of range [member] | Tranche Two [Member]
Decrease percentage of derivative value			31%
Increase percentage of derivative value			31%
share price [member] | Bottom of range [member] | Tranche Two [Member]
Decrease percentage of derivative value			17%
Increase percentage of derivative value			17%

Agreements with General Motor_3

Agreements with General Motors - Schedule of Change in the value of derivative agreement (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Equity [abstract]
On initial recognition as at January 30, 2023	$ (33,194)
Gain on change in fair value	32,846
As at December 31, 2023	$ (348)

Leases and Other Liabilities -

Leases and Other Liabilities - Summary of Leases and Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of quantitative information about leases and other liabilities [line items]
Lease liabilities	$ 3,113	$ 1,618	$ 1,755
Mining contractor liability	3,500	5,950	5,940
Other liabilities	6,613	7,568	7,695
Office leases [member]
Disclosure of quantitative information about leases and other liabilities [line items]
Lease liabilities	1,199	1,614	1,743
Cars and equipment leases [member]
Disclosure of quantitative information about leases and other liabilities [line items]
Lease liabilities	69	4	12
Land lease [member]
Disclosure of quantitative information about leases and other liabilities [line items]
Lease liabilities	$ 1,845	$ 0	$ 0

Leases and Other Liabilities _2

Leases and Other Liabilities - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Instalments	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Disclosure of detailed information about other liabilities [line Items]
Mining contractor liability	$ 3,500	$ 5,950	$ 5,940
Success fee to mining contractor	4,675
Repayment amount upon failing to achieve milestone	$ 3,500
Office space, cars and equipment [member] | Bottom of range [member]
Disclosure of detailed information about other liabilities [line Items]
Leases useful life	2 years
Office space, cars and equipment [member] | Top of range [member]
Disclosure of detailed information about other liabilities [line Items]
Leases useful life	5 years
Land lease [member]
Disclosure of detailed information about other liabilities [line Items]
Leases useful life	40 years
Thacker Pass [Member]
Disclosure of detailed information about other liabilities [line Items]
Number of instalments | Instalments	7
Mining contractor liability	$ 3,500			$ 2,000	$ 1,500

Share Capital and Equity Comp_3

Share Capital and Equity Compensation - Additional Information (Details)		12 Months Ended
	Oct. 03, 2023 USD ($) shares $ / shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares outstanding | shares	160,048,000
Operating expense		$ 27,625,000	$ 60,857,000	$ 44,495,000
Capitalized for thacker pass project			0	0
Old lac [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares outstanding | shares	0
Stock options granted terms	5 years
Ordinary shares [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares issued | shares		161,778,000
Number of shares outstanding | shares		161,778,000
Preference shares [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares issued | shares	1,000,000,000
RSUs [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares issued | shares	2,171,000
Number shares granted | shares	670,000	0.670
Estimated fair value	$ 4,878,000
Unrecognized compensation cost related to unvested share based compensation arrangements		$ 4,642,000
Fair value of share units recorded as a share-based payments expense		3,462,000
Operating expense		964,000	3,058,000	2,100,000
Capitalized for thacker pass project		1,460,000
Per share value of rearrangement | $ / shares	$ 0.87
DSUs [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares outstanding | shares	225,000
Per share value of rearrangement | $ / shares	$ 0.87
PSUs [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of shares issued | shares	1,037,000
Unrecognized compensation cost related to unvested share based compensation arrangements		2,174,000	206,000
Fair value of share units recorded as a share-based payments expense		4,126,000
Operating expense		1,140,000	979,000	1,166,000
Capitalized for thacker pass project		$ 256,000	$ 0	$ 0
Per share value of rearrangement | $ / shares	$ 0.87

Share Capital and Equity Comp_4

Share Capital and Equity Compensation - Summary of Changes to the Number of Shares Outstanding (Details) - shares		12 Months Ended
	Oct. 03, 2023	Dec. 31, 2023
RSUs [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued on separation		2.171
Converted into shares		(1.191)
Granted	670,000	0.670
Number of shares outstanding balance		1.650
DSUs [Member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued on separation		225,000
Converted into shares		(130,000)
Number of shares outstanding balance		95,000
PSUs [member]
Disclosure of terms and conditions of share-based payment arrangement [line items]
Issued on separation		1,037,000
Converted into shares		(409,000)
Number of shares outstanding balance		628,000

Related Party Transactions - Su

Related Party Transactions - Summary of Compensation of Directors and Key Management (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended			12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 02, 2023	Oct. 02, 2022	Oct. 02, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related party transactions [abstract]
Salaries, bonuses, benefits and directors' fees included in the Consolidated Statements of Comprehensive Loss	$ 2,481	$ 2,557	$ 509	$ 1,499	$ 1,303	$ 901
Salaries, bonuses and benefits included in PP&E	576	0	0	242	0	0
Equity compensation	1,538	361	132	$ 1,670	$ 644	$ 672
Total for the year ended December 31,							$ 8,006	$ 4,865	$ 2,214
Total due to directors and key management	$ 2,376	$ 1,415	$ 671				$ 2,376	$ 1,415	$ 671

General and Administrative Ex_3

General and Administrative Expenses - Summary of Company's General and Administrative Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	$ 16,274	$ 9,545	$ 5,116
Salaries, Benefits and Directors Fees
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	7,973	3,485	2,108
Office and Administration
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	3,788	1,619	1,157
Professional Fees
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	2,525	3,426	1,205
Regulatory and Filing Fees
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	374	161	214
Travel
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	450	334	67
Investor Relations
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	998	350	231
Depreciation
Disclosure of attribution of expenses by nature to their function [line items]
General and administrative expenses	$ 166	$ 170	$ 134

Exploration and Evaluation Ex_3

Exploration and Evaluation Expenditures - Summary of Company's Exploration and Evaluation Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	$ 3,763	$ 47,275	$ 36,113
Consulting and salaries [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	2,405	10,840	7,395
Engineering [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	782	27,928	23,009
Permitting and environmental [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	268	3,285	2,391
Field supplies and other [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	14	1,592	942
Depreciation [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	196	1,520	658
Drilling and geological expenses [member]
Disclosure of assets recognised from costs to obtain or fulfil contracts with customers [line items]
Exploration and evaluation expenditures	$ 98	$ 2,110	$ 1,718

Transactions Costs - Summary Of

Transactions Costs - Summary Of Transactions Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Trading income (expense) [abstract]
Separation cost allocation	$ 4,626	$ 0	$ 0
ATVM Loan due diligence costs	3,138	0	0
General Motors investment	2,777	0	0
Total transactions costs	$ 10,541	$ 0	$ 0

Finance Costs - Summarizes the

Finance Costs - Summarizes the Company's Finance Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finance Costs [abstract]
Accrued interest on loan from former parent	$ 301	$ 3,591	$ 2,359
Other	47	448	292
Finance costs	$ 348	$ 4,039	$ 2,651

Finance and Other Income (Expen

Finance and Other Income (Expenses) - Summary of Finance and Other Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finance and other income [abstract]
Interest earned on cash deposits	$ 2,945
Other	78	$ (338)	$ (2)
Finance and Other Income	$ 3,023	$ (338)	$ (2)

Segmented Information - Additio

Segmented Information - Additional Information (Details)	12 Months Ended
	Dec. 31, 2023 Area Segment
Disclosure of operating segments [abstract]
Number of operating segment | Segment	1
Number of geographic areas | Area	1

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Income Taxes at Canadian Statutory Rates with Reported Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Major components of tax expense (income) [abstract]
Loss from operations before tax	$ (3,934)	$ (67,798)	$ (47,148)
Gain from discontinued operations			122
(Loss)/Income before tax	$ (3,934)	$ (67,798)	$ (47,026)
Statutory tax rate	27%	27%	27%
Expected income tax recovery at statutory tax rate	$ (1,062)	$ (18,305)	$ (12,697)
Items not taxable for income tax purposes	(6,172)	0	0
Effect of lower tax rate in foreign jurisdiction	640	3,241	2,417
Change in unrecognized deferred tax assets and other	6,594	15,064	10,280
Total tax expense (income)	$ 0	$ 0	$ 0

Income Taxes - Summary of Signi

Income Taxes - Summary of Significant Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	$ 53,772	$ 44,780	$ 31,977
Deferred tax liabilities	(11,000)	(4,845)	0
Unrecognized deferred tax assets	42,772	39,935	31,977
Exploration and evaluation assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	3,507	3,602	1,173
Property, plant and equipment (including right-of-use assets) [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	0	536	0
Investment in Green Technology Metals [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	1,004	346	0
Investment in Ascend Elements [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	0	0	0
Deferred tax liabilities	(484)	0	0
Other [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	1,724	100	109
Capital assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax liabilities	(163)	0	0
Thacker Pass assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax liabilities	(4,631)	0	0
Equity compensation [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax liabilities	(5,722)	(4,845)	0
Tax loss carryforwards [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets	$ 47,537	$ 40,196	$ 30,695

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets not recognized	$ 203,836	$ 200,482
Deferred tax assets are recognized	$ 0	$ 0
Canada [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Non-capital loss carryforwards expiration year period	2043
US [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Non-capital loss carry-forwards	$ 219,311
Non-capital loss carryforwards expiration year period	between 2029 and 2037
Expiring between 2042 - 2043 [member] | Canada [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Non-capital loss carry-forwards	$ 5,488
Expires between 2029 and 2037 [member] | US [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Non-capital loss carry-forwards	38,756
No expiration [Member] | US [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Non-capital loss carry-forwards	$ 180,555

Supplemental Cash Flow Inform_3

Supplemental Cash Flow Information - Schedule of supplemental cash flow information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Supplemental cash flow [abstract]
Interest received on cash deposits	$ 1,373	$ 0	$ 0
Interest paid	$ 278	$ 462	$ 293

Financial Instruments - Summary

Financial Instruments - Summary of the contractual maturities of the Company's financial liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Accounts payable and accrued liabilities	$ 23,361	$ 9,913	$ 4,214
Obligations under office leases	2,161
Obligations under land leases	4,034
Other obligations	3,628
Financial liabilities on undiscounted basis ,Total	33,184
Later than one year [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Accounts payable and accrued liabilities	23,361
Obligations under office leases	884
Obligations under land leases	69
Other obligations	54
Financial liabilities on undiscounted basis ,Total	24,368
Later than one year and not later than two years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Accounts payable and accrued liabilities	0
Obligations under office leases	565
Obligations under land leases	70
Other obligations	3,551
Financial liabilities on undiscounted basis ,Total	4,186
Later than two years and not later than three years [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Accounts payable and accrued liabilities	0
Obligations under office leases	712
Obligations under land leases	73
Other obligations	23
Financial liabilities on undiscounted basis ,Total	808
Later than three years and later [member]
Disclosure of maturity analysis for non-derivative financial liabilities [line items]
Accounts payable and accrued liabilities	0
Obligations under office leases	0
Obligations under land leases	3,822
Other obligations	0
Financial liabilities on undiscounted basis ,Total	$ 3,822

Financial Instruments - Additio

Financial Instruments - Additional Information (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CAD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 195,516	$ 8.5	$ 636	$ 933	$ 512
Current liabilities	$ 24,563		$ 54,209	$ 4,517
Average foreign exchange rate	10
Net foreign exchange gain (loss)	$ 848
Credit risk [member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	195,516
Current liabilities	$ 24,563

Discontinued Operation - Additi

Discontinued Operation - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
	Jan. 13, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disclosure of analysis of single amount of discontinued operations [line items]
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations		$ 0	$ 0	$ 4,034
Discontinued operations [member]
Disclosure of analysis of single amount of discontinued operations [line items]
Proceeds from disposal of non-current assets or disposal groups classified as held for sale and discontinued operations	$ 4,034

Discontinued Operation - Schedu

Discontinued Operation - Schedule of Discontinued Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Expenses
Total expense	$ (27,625)	$ (60,857)	$ (44,495)
Net income from discontinued operation	0	0	122
Discontinued operations [member]
Disclosure of analysis of single amount of discontinued operations [line items]
Organoclay sales	0	0	18
Cost of sales	0	0	(42)
Gross Loss	0	0	(24)
Expenses
General, administrative, and other	0	0	(37)
Total expense	0	0	(37)
Other income	0	0	25
Gain on sale of assets	0	0	158
Net income from discontinued operation	0	0	122
Net cash inflow from discountinued operation	$ 0	$ 0	$ 3,523

Subsequent Event - Additional I

Subsequent Event - Additional Information (Details) $ in Millions	Mar. 12, 2024 USD ($)
Subsequent events [member]
Disclosure of non-adjusting events after reporting period [line items]
Gross loan commitments	$ 2,260