Pumice and pumicite

Production of pumice in the United States during 2011 was estimated to be 380 kt (420,000 st), a 3-percent decrease compared with 2010. The unit value of pumice varied by end use in 2011. Pumice used as an abrasive was priced at $10.39/t ($9.30/st), while specialty-grade pumice, used in cosmetics, filtration or precision grinding, was priced as high as $150/t ($130/st) on a spot basis. Fourteen companies operated 16 mines in Arizona, California, Idaho, Kansas, New Mexico and Oregon. U.S. pumice exports totaled about 15 kt (17,000 st). Imports were higher, 35 kt (39,000 st).