Exhibit 99.1

      FOR IMMEDIATE RELEASE                    CONTACT: James P. Kelly
                                                    Director, Investor Relations
                                                    (617) 342-6244
                                                    jim_kelly@cabot-corp.com

                                                    Ethel Shepard
                                                    Corporate Affairs Manager
                                                    (617) 342-6254
                                                    ethel_shepard@cabot-corp.com

                STATOIL TO USE CABOT CESIUM FORMATE FLUIDS ON TWO
                         MAJOR HIGH PRESSURE GAS FIELDS

BOSTON, MA (June 13, 2003) - Cabot Corporation (NYSE:CBT) announced today that
its Cabot Specialty Fluids business has signed a letter of intent with a major
energy service company to provide a supply of cesium formate fluids for both
reservoir drilling and completion activities on two large gas and condensate
field projects in the Norwegian Continental Shelf. The fields, Kristin and
Kvitebjorn, are being developed and will be operated by Statoil (NYSE:STO). If
the cesium formate fluids perform as anticipated, they could be used in more
than 20 drilling and completion projects in these fields over the next several
years.

Concerning the letter of intent, Ken Burnes, Cabot's Chairman and CEO, stated
"We are very excited about the opportunity to establish a significant
relationship with a major company such as Statoil on these projects. Successful
performance of cesium formate drilling fluids on the projects would demonstrate
to a broader customer base that these fluids provide the most effective drill-in
and completion solution in high-temperature, high-pressure wells. We are also
optimistic that this indicates an increase in HTHP drilling activity."

                                                    (more)

About Cesium Formate

Cesium formate is a dense biodegradable drilling and completion fluid that is
used as a solids-free base fluid for large-scale drilling and completion
projects. The fluids can be used in a wide range of applications in areas that
allow oilfield-operating companies to increase production and improve their
drilling speed, which can save time and reduce operating costs. Cabot cesium
formate has been used successfully in numerous drilling and completion
operations for several major oil companies in the UK and Norwegian North Sea
sectors.

Cesium formate is also proven to be compatible with all major elements of the
drilling (BOP, surface equipment, MWD, LWD and mud motors) and completion
equipment (metals and elastomers), under conditions of high temperature and
pressure.

The monovalent nature of cesium formate reduces the likelihood of reservoir
formation damage, providing operators with a maximized production index and
overall production profile. Because it is biodegradable as well as
non-corrosive, cesium formate is considered an environmentally safer product
than other drilling fluids on the market.

About Cabot

Cabot Corporation is a global specialty chemicals and materials company and is
headquartered in Boston, MA. Cabot's major products are carbon black, fumed
silica, inkjet colorants, capacitor materials and cesium formate drilling
fluids. Cabot has approximately 4,500 employees in 45 manufacturing plants
located in 23 countries around the world. www.cabot-corp.com

FORWARD-LOOKING INFORMATION: Included above are forward-looking statements
relating to management's expectations of future profits, the possible
achievement of the Company's financial goals and objectives and management's
expectations for shareholder value creation initiatives and for the Company's
product development program. Actual results may differ materially from the
results anticipated in the forward-looking statements included in this press
release due to a variety of factors, including market supply and demand
conditions, fluctuations in currency exchange rates, costs and availability of
raw materials, patent rights of others, stock market conditions, demand for our
customers' products, competitors' reactions to market conditions, the outcome of
pending litigation and governmental investigations, the impact of global health
and safety concerns on economic conditions or market opportunities and other
factors discussed in the Company's 2002 Annual Report on Form 10-K. Timely
commercialization of products under development by the Company may be disrupted
or delayed by technical difficulties, market acceptance, competitors' new
products, as well as difficulties in moving from the experimental stage to the
production stage.

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