Minerals

The USGS Earth Mapping Resource Initiative (Earth MRI) is a partnership of the USGS, the Association of American State Geologists and other governmental, Tribal and private sector entities to update the nation’s surface and subsurface mapping, to improve our knowledge of the geologic framework in the United States and to identify areas that may have the potential to contain undiscovered critical...

Mining records for shaft mining used to be maintained by the U.S. Bureau of Mines, which closed in 1996. Their records are in the National Archives and National Technical Reports Library. States are currently the best source for mine ownership records. The USGS Mineral Resources Data System (MRDS) might provide some information. The U.S. Bureau of Mines database MAS/MILS (Mineral Availability...

The Energy Act of 2020 defined critical minerals as those that are essential to the economic or national security of the United States; have a supply chain that is vulnerable to disruption; and serve an essential function in the manufacturing of a product, the absence of which would have significant consequences for the economic or national security of the U.S. The act further specified that...

After 85 years of service, the U.S. Bureau of Mines (USBM) closed in 1996. Certain functions, such as the collection, analysis, and dissemination of minerals information, have been returned to the U.S. Geological Survey (USGS). For information on former USBM programs or publications, please see the following sources: The National Technical Reports Library (part of the National Technical...

White gold was originally developed to imitate platinum (a naturally white metal). White gold is usually an alloy containing about 75% gold and about 25% nickel and zinc. If stamped 18 karat, it would be 75% pure gold.

For statistical information about mineral commodities, visit the USGS Commodity Statistics and Information website. For locations outside the United States, USGS International Minerals Statistics and Information is the best starting point.

The fineness of jewelry gold is stated as the number of parts in twenty-four that are gold. Thus, 24 karat gold is pure gold; 12 K would be an alloy that is half gold and half copper or other metals.

A mineral is a naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties. Common minerals include quartz, feldspar, mica, amphibole, olivine, and calcite. A rock is an aggregate of one or more minerals, or a body of undifferentiated mineral matter. Common rocks include granite, basalt...

Of the 1,740,000 metric tons of silver discovered to date, 55% is found in just four countries on earth. All the silver discovered thus far would fit in a cube 55 meters on a side. Learn more: USGS commodity website for silver

Fool's Gold can be one of three minerals. The most common mineral mistaken for gold is pyrite. Chalcopyrite may also appear gold-like, and weathered mica can mimic gold as well. Compared to actual gold, these minerals will flake, powder, or crumble when poked with a metal point, whereas gold will gouge or indent like soft lead. In addition, actual gold will leave a golden yellow streak when...

Sterling silver is the standard of quality for articles containing 92.5% silver and 7.5% copper (and/or other alloys).

About 244,000 metric tons of gold has been discovered to date (187,000 metric tons historically produced plus current underground reserves of 57,000 metric tons). Most of that gold has come from just three countries: China, Australia, and South Africa. The United States ranked fourth in gold production in 2016. All of the gold discovered thus far would fit in a cube that is 23 meters wide on every...