From abstract: Deposits of vanadium-bearing sandstone are widely distributed in western Colorado and eastern Utah and have been the principal domestic source of vanadium, uranium, and radium. Except during a few years when operations were relatively small, deposits at one or more places in this region have been intensively mined since 1909. Production has increased considerably each year since 1937.

From Introduction: "Scattered throughout the Colorado Front Range, there are many small copper deposits, believed to be of pre-Cambrian age. The have been widely prospected but have produced little or no ore. In one of these, the Copper King mine, near Gold Hill, Colo., nickel was discovered in 1930, and development in the following years has exposed some 25,000 tons of ore containing from 2 to 3 percent of nickel. No other nickel deposit is known in the Front Range, but a somewhat similar deposit has been opened in Gem mine, near Canon City and about 120 miles south of Gold Hill."