Acme-Hardesty Co.

General Chemical

 PPG Industries

 Airgas

 Imerys

 PQ Corporation

 Allied Signal

 Innophos

Puritan Products

American Colloid

 International Metals

 Reheis

Americhem

 International Specialty Products

 Rhodia

Andersons

 Jones Hamilton

 Roquette Corp.

 Ashta Chemical

 Jungbunzlauer

 Rot Quimica

 Atotech

 Kemiron

 Solvay Chemicals

 BP Chemicals

 MacDermid Inc.

 SQM North America

 Cargill

 Mosaic

 Sun Co.

 Celite

 Nitrochem Inc.

 U.F. Strainrite

 Church & Dwight

 North American Salt

 U.S. Borax

 Degussa

 Occidental Chemical

 U.S. Gypsum

 Dow Chemical

 Oil Associates

 Unocal

 Engelhard Materials

 Olin Chemicals

 Velsicol

FMC Corp.

 Pioneer

World Minerals