| Lafarge Corp (Girard, OH)
|
| M Brashem Inc (Bellevue, WA)
|
| Milwhite Inc (Van Horn, TX)
|
| Multi Serv (Warren, OH)
|
| Multi Serv (Mansfield, OH)
|
| Nevada Star Resource Corp (Bellevue, WA)
|
| Olympic Mill Svc (Lemont, IL)
|
| Operation Hope (Jackson, TN)
|
| Oxbow (Aurora, IN)
|
| Penna Perlite Corp of York (York, PA)
|
| Pennsylvania Perlite Corp (Bethlehem, PA)
|
| Polymer Drilling Systems (El Dorado, AR)
|
| Ray Brown Enterprises (Woodruff, SC)
|
| Southern Clay Products Inc (Gonzales, TX)
|
| Sprunger's Minerals (Delta, UT)
|
| Superior Sand Co (Friendsville, MD)
|
| Therm-O-Rock East Inc (New Eagle, PA)
|
| Unimin Corp (Mauk, GA)
|
| United States Pumice Co (Lee Vining, CA)
|
| Virginia Vermiculite Ltd (Louisa, VA)
|
