Uranium,
a radioactive element, was first mined in the western United States
in 1871 by Dr. Richard Pierce, who shipped 200 pounds of pitchblende
to London from the Central City Mining District near Denver, Colorado.
The ore was researched for fabrication of steel alloys, chemical experimentation
and as pigments for dyes, inks and stained glass.
In
1898 Pierre and Marie Curie and G. Bemont isolated the "miracle element"
radium from pitchblende. That same year, uranium, vanadium and radium
were found to exist in carnotite, a mineral containing colorful red
and yellow ores that had been used as body paint by early Navajo and
Ute Indians on the Colorado Plateau. The discovery triggered a small
prospecting boom in southeastern Utah, and radium mines in Grand and
San Juan counties became a major source of ore for the Curies.