Estimated domestic production of pumice and pumicite during 2000 increased about 16 percent from 1999, according to the US Geological Survey (USGS). Revised figures for 1999 domestic production were a record 643 kt (707,000 st), according to the agency. That was up 60 kt (66,000 st) from 1998.The USGS estimated the value of pumice and pumicite sold or used in the United States during 2000 to be
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