Feb 172017
IS-79 Colorado Mineral and Energy Industry Activities 2015-16 (cover)

The current annual Colorado Mineral and Energy Industry Activities report 2015-16 is now available. Following up on the 2014 report, this report, based on 2015 production data, sketches a comprehensive overview of Colorado’s mineral resource production. Of note is the fact that total value of mineral and energy fuels production in Colorado for 2015 is estimated to be $13.43 billion, a 29% decline from the $18.8 billion production value in 2014. The decline was caused primarily by a precipitous decrease in oil and gas market prices which provide 70% of Colorado mineral resource revenue. Oil and gas production actually registered at all-time highs of 127.6 Mbbl and 1,709 Bcf, respectively.

Nonfuel mineral production — including metals, industrial minerals, and construction materials — posted a modest 3.9% increase in revenue. Increased production of crushed stone, cement, and sand and gravel aggregate accounted for the increase. With a 2015 production of 21,790 metric tons of molybdenum from two mines, Colorado is the largest molybdenum producer in the U.S. Although just one mine in the state publicly reported gold production in 2015, Colorado remains the third largest producer of the metal in the U.S. as it was in 2014.

Citation: Cappa, James A., Michael K. O’Keefe, James R. Guilinger, and Karen A. Berry. “IS-79 Colorado Mineral and Energy Industry Activities 2015-16.” Mineral and Energy Industry. Information Series. Golden, CO: Colorado Geological Survey, 2016.
Feb 142017

Uranium is a widespread and ubiquitous element. It has a crustal abundance of 2.8 parts per million, slightly more than tin. Primary deposits of uranium tend to concentrate in granitic or alkalic volcanic rocks, hydrothermal veins, marine black shales, and early Precambrian age placer deposits. Secondary (or epigenetic) deposits of uranium are formed later than the surrounding rocks that host the mineral deposit. Uranium is soluble in oxidizing aqueous solutions, especially the U+6 valence state, and can be redistributed from primary source rocks into porous sedimentary rocks and structures by groundwater and form secondary (epigenetic) uranium mineral deposits.

Epigenetic deposits of uranium in sedimentary rocks form the bulk of uranium deposits in Colorado. These include the many mines of the Uravan, Cochetopa, Maybe, and Rifle districts, and other scattered places including the Front Range and Denver Basin. Primary uranium deposits in Colorado occur in hydrothermal veins, especially in the Front Range. Continue reading »