Segment Results
Heavy Materials: Cement, Concrete and Aggregates
Revenue in the Heavy Materials sector, which includes Cement, Concrete and Aggregates, as well as Joint Venture and intersegment Cement revenue, was $277.6 million, a 21% improvement. Heavy Materials operating earnings increased 31% to $75.5 million primarily because of improved Cement net sales prices and earnings from the recently acquired Kosmos Cement Business.
Cement revenue for the quarter, including Joint Venture and intersegment revenue, was up 28% to $234.1 million, and operating earnings were $70.4 million, up 30%. These increases reflect improved Cement net sales prices and the significant contribution of the recently acquired Kosmos Cement Business, which accounted for approximately $45 million of revenue and $13 million of operating earnings during the quarter.
The average net sales price for the quarter increased 2% to $111.91 per ton. Excluding the impact from the Kosmos Cement Business, the average net sales price increased 4%. Cement sales volume for the quarter was 1.8 million tons, up 28% versus the prior-year period. Excluding the impact from the Kosmos Cement Business, our Cement sales volume was flat with the prior-year period.
Concrete and Aggregates revenue decreased 7% to $43.5 million. The decline reflects the sale of our Northern California concrete and aggregates businesses during the first quarter of fiscal 2021. Excluding the results from the sold businesses, Concrete and Aggregates revenue was up 13%. Third quarter operating earnings for Concrete and Aggregates increased 52% to $5.1 million, primarily reflecting improvements in organic Concrete sales volume, Concrete sales prices, and operating efficiencies, as well as lower diesel fuel costs.
Light Materials: Gypsum Wallboard and Paperboard
Revenue in the Light Materials sector, which includes Gypsum Wallboard and Paperboard, increased 8%, reflecting improved Wallboard sales volume and pricing. Gypsum Wallboard sales volume was a third quarter record of 727 million square feet (MMSF), up 9%, while the average Gypsum Wallboard net sales price increased 1% to $147.87 per MSF. Given the improved demand outlook for single-family construction activity in the US and increasing demand for our products, our American Gypsum wallboard business implemented a wallboard price increase during the quarter and another increase in early January.
Paperboard sales volume for the quarter declined 1% to 79,000 tons. The average Paperboard net sales price was $484.92 per ton, up 5% from the prior year, consistent with the pricing provisions in our long-term sales agreements.
Operating earnings were $48.0 million in the sector, an increase of 1%, reflecting improved Wallboard sales volume and pricing, partially offset by higher operating costs, primarily due to higher recycled fiber costs.
Sale of Oil and Gas Proppants Business
On September 18, 2020, the Company sold its Oil and Gas Proppants business to Smart Sand, Inc. The current-year and prior-year financial results of the Oil and Gas Proppants segment have been classified as Discontinued Operations on the Statement of Earnings. The assets and liabilities of the Oil and Gas Proppants segment have been reflected on separate lines for Discontinued Operations on the Balance Sheet.
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