PRICE INCREASE

Imerys in North America Announces Price Increases for Filtration and Functional Filler Products

September 23, 2011

Santa Barbara, California

Imerys Performance & Filtration Minerals, formally World Minerals Inc., will raise prices for products shipped within North America effective November 1, 2011. The increase will range 4 to 12%, subject to any provisions in individual contracts. The price increase supports investments in manufacturing and maintenance, quality systems, environmental compliance, and new products, and to offset increased production costs. The price increases will affect all diatomite, perlite, cellulose, and silicate products. The energy surcharge will remain in effect.

Imerys, an industrial minerals company and a world leader in the manufacturing of high quality filter aids and functional mineral additives, is headquartered in Paris, France, with operations in North and South America, Europe and Asia-Pacific. More information on performance and filtration products is available on the website (www.worldminerals.com).

The world leader in adding value to minerals, Imerys is active in 47 countries with more than 240 sites. Number one in the world for minerals for filtration, diatomite and perlite products, Imerys mines, researches and delivers innovative mineral solutions for some of the largest companies in the world. Now with a broad range of worldwide diatomite and perlite reserves, Imerys products have many applications in everyday life, including beverage filtration, paint, plastic, construction, pharmaceutical and personal care. Imerys is investing and innovating for the future with revolutionary products like Celite Cynergy, which is redefining beer filtration. More comprehensive information on Imerys can be found on the Group’s website, www.imerys.com

For further information please contact us.