Talk:Psilomelane

Latest comment: 9 years ago by 71.182.238.243

This article reports that psilomelane is "is extensively mined in Vermont, Virginia, Arkansas". According to the United States Geological Survey's mineral commodity summaries, no manganese ore containing more than 20% manganese has been produced in the United States since 1970. http://minerals.usgs.gov/minerals/pubs/commodity/manganese/mcs-2015-manga.pdf — Preceding unsigned comment added by 71.182.238.243 (talk) 18:44, 18 April 2015 (UTC)Reply