@misc{indiciae6c5c3e229ae9, title = {Mineral Commodity Summaries 2000}, author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey}, year = {2000}, doi = {10.3133/mineral2000}, url = {https://pubs.usgs.gov/publication/mineral2000}, note = {Source identifier: mineral2000} }