Thirty-five occurrences of radioactive rocks had been reported from Nevada
prior to 1952. Twenty-five of these had been investigated by personnel of the
U. S. Geological Surveyor of the U. S. Atomic Energy Commission. Of those
investigated, uranium minerals were identified at 13 sites; two sites contained a thorium mineral (monazite); the source of radioactivity on nine properties was not ascertained, and one showed no abnormal radioactivity. Of the other
reported occurrences, one is said to contain uraniferous hydrocarbons and nine
are placers containing thorian monazite.
Pitchblende occurs at two localities, the East Walker River area, and the
Stalin's Present prospect, where it is sparsely disseminated in tabular bodies
cutting granitic rocks. Other uranium minerals found in the state include:
carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite,
and an unidentified mineral which may be dumontite. Monazite is the only thorium mineral of possible economic importance that has been reported.
From an economic standpoint, only four of the properties examined showed
reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951; the Majuba Hill mine; the Stalin's Present prospect; and the West Willys claim in the Washington district. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.