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Global Geochemical Database for Critical Minerals in Archived Mine Samples

June 22, 2020

The Critical Minerals in Archived Mine Samples Database (CMDB) contains chemistry and geologic information for historic ore and ore-related rock samples from mineral deposits in the United States. In addition, the database contains samples from archetypal deposits from 27 other countries in North America, South America, Asia, Africa and Europe. Samples were obtained from archived ore collections under the U.S. Geological Survey's project titled "Quick Assessment of Rare and Critical Metals in Ore Deposits: A National Assessment" (2008 to 2013) in an effort to begin an assessment of the Nations' previously mined ore deposits for critical minerals. Mineralized and altered rock samples were provided by the Colorado School of Mines - Ransome collection, Mackay School of Mines - Stanford and Keck collections, and by the personal collections of Don Bryant and David Leach.