Webcast Alert: Crompton Corporation Announces Q2 2004 Crompton Corporation Earnings Release Webcast.

Crompton Corporation announces the following Webcast:

    What:     Q2 2004 Crompton Corporation Earnings Release     When:     July 23rd, 2004 @ 8:00 AM ET     Where:    http://www.firstcallevents.com/service/ajwz408912347gf12.html     How:      Live over the Internet -- Simply log on to the web at the              address above.     Contact:  Lori Kim, Corporate Communications Specialist, +1-203-573-2163              kimlo@cromptoncorp.com   

If you are unable to participate during the live webcast, the call will be archived at http://www.firstcallevents.com/service/ajwz408912347gf12.html

Crompton Corporation, with annual sales of $2.2 billion, is a producer and marketer of specialty chemicals and polymer products and equipment providing the solutions, service and value our customers need to succeed. It has approximately 5,500 employees and key manufacturing facilities worldwide.

Available in 120 countries, the company products include: polymers, polymer additives and polymer processing equipment; organofunctional silanes and specialty silicones; crop protection chemicals, petroleum additives, and refined products.

Crompton's 113 million outstanding common shares are traded on the New York Stock Exchange under the symbol CK.

CONTACT: Lori Kim, Corporate Communications Specialist of Crompton Corporation, +1-203-573-2163, kimlo@cromptoncorp.com