Databases of mineral deposits and occurrences are essential to conducting assessments of undiscovered mineral resources. In the USGS's (U.S. Geological Survey) global assessment of undiscovered resources of copper, potash, and the platinum-group elements (PGE), only a few mineral deposit types will be evaluated. For example, only porphyry-copper and sediment-hosted copper deposits will be considered for the copper assessment. To support the global assessment, the USGS prepared comprehensive compilations of the occurrences of these two deposit types in order to develop grade and tonnage models and delineate permissive areas for undiscovered deposits of those types.
This publication identifies previously published databases and database records that describe PGE, nickel, and chromium deposits and occurrences. Nickel and chromium were included in this overview because of the close association of PGE with nickel and chromium mineralization. Users of this database will need to refer to the original databases for detailed information about the deposits and occurrences. This information will be used to develop a current and comprehensive global database of PGE deposits and occurrences.