Wyoming Metals

Wyoming has produced both precious and base metals in the past. Precious metals are relatively scarce and include gold, silver, and the platinum group metals. Base metals are those of relatively inferior value compared to precious metals. Base metals are generally more chemically active than precious metals and include copper, lead, zinc, and molybdenum.

Although significant metals production has not occurred since iron ore mining ended at South Pass in 1983, fluctuating metals prices during recent years have spurred erratic interest in, and increased exploration for, Wyoming’s gold, platinum, copper, iron, rare earth elements REE), titanium, and related metals.

Precambrian rocks exposed in the cores of mountain uplifts, Tertiary volcanic and intrusive rocks, and related placer deposits are the dominant hosts for Wyoming’s metal resources. However, some metal deposits also occur in Phanerozoic sedimentary rocks. The Archean craton, also known as the Wyoming Craton (or Province), is part of the ancient core of the North American continent and dominates Wyoming’s Precambrian rock exposures. The Archean rocks are more than 2.5 billion years old and are often compared to rocks in some of the world’s richest precious metal producing areas such as the Archean cratons of Western Australia, South Africa, and the Superior Province of Canada.

Gold, copper, and iron have all been mined from these rocks in Wyoming. Younger Precambrian (Proterozoic) rocks accreted along the south edge of the Archean craton in the Medicine Bow Mountains and in the Sierra Madre include two large layered mafic-ultramafic complexes and a variety of intrusive and metamorphic rocks that host both base and precious metals, including platinum. Tertiary volcanic, sub-volcanic, and related rocks in the Absaroka volcanic plateau in northwest Wyoming host large base and precious metal deposits. Tertiary intrusive rocks in the Rattlesnake Hills of central Wyoming carry disseminated gold, and Tertiary intrusive rocks in the Bear Lodge Mountains in northeast Wyoming host significant REE and thorium deposits along with low-grade gold mineralization.

Carissa mine at the South Pass City State Historic Site. [Credit: Wayne M. Sutherland, WSGS]

Principal Metal Districts and Areas of Wyoming

Metals Publications

Publications relating to metals can be downloaded or purchased from the metals category of the online catalog.


Patty Webber, patty.webber@wyo.gov