The U. S. Geological Survey, on behalf of the Atomic Energy Commission,
from July 1951 to February 1952, explored the Lost Creek schroeckingerite
deposit, Sweetwater County, Wyoming, by means of auger- drilling, trenching, and
bucket-drilling. This report presents an estimate of the inferred ore reserves
obtained during this exploration.
The inferred reserves are presented under three schedules. Schedule A is
the reserves calculated for the main schroeckingerite-bearing area; Schedule B
is the reserves for the smaller schroeckingerite-bearing area to the north of
the main area. The grade and tonnage estimates for both Schedule A and Schedule
B are divided into two groups--data for selective mining, and data for bulk-mining.
Schedule C presents reserve estimates for a semi- selective mining method
and was calculated for four selected blocks in the western half of the main
The inferred reserves of schroeckingerite available for bulk-mining in the
area of Schedule A are about 3,000,000 tons that contain 0.005 percent uranium,
or about 140 tons of metallic uranium. By bulk-mining, 900,000 tons containing
0.005 percent uranium, or U£ tons of metallic uranium, are available in the
area of Schedule B.
The inferred reserves available for selective mining in the area of
Schedule A are 100,000 tons of schroeckingerite deposits that contain 0.030
percent uranium, or 30 tons of metallic uranium. By selective mining, 35,000
tons of schroeckingerite deposits that contain the 0.030 percent uranium, or
10 tons of metallic uranium, are available in the area of Schedule Bo
Semi- selective mining in the four areas of Schedule C will yield about
650,000 tons of rock containing O.008 percent uranium, or 50 tons of metallic