Mineral Resources Data System

Mineral resource occurrence data covering the world, most thoroughly
within the U.S. This database contains the records previously
provided in the Mineral Resource Data System (MRDS) of USGS and the
Mineral Availability System/Mineral Industry Locator System
(MAS/MILS) originated in the U.S. Bureau of Mines, which is now part
of USGS.
The MRDS is a large and complex relational database developed over
several decades by hundreds of researchers and reporters. While
database records describe mineral resources worldwide, the
compilation of information was intended to cover the United States
completely, and its coverage of resources in other countries is
incomplete.
The content of MRDS records was drawn from reports previously
published or made available to USGS researchers. Some of those
original source materials are no longer available.
The information contained in MRDS was intended to reflect the
reports used as sources and is current only as of the date of those
source reports. Consequently MRDS does not reflect up-to-date
changes to the operating status of mines, ownership, land status,
production figures and estimates of reserves and resources, or the
nature, size, and extent of workings. Information on the
geological characteristics of the mineral resource are likely to
remain correct, but aspects involving human activity are likely to
be out of date.