NI43-101Pre-Feasibility Study Report - page 109

Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
, 2014
10135-200-46 - Rev. 0
The Company also completed a TEM geophysical survey and had all pre-existing
core analyzed for REE content. Molycorp withdrew from the joint venture in 1980.
Duval continued with a diminished level of exploration activity until September 1984.
With the divestiture of Duval and spin-off of Battle Mountain Gold Company, the
property was abandoned after management rejected a recommended rare earth
metallurgical feasibility study.
The USGS conducted field and laboratory studies on the property between 1975 and
1979, including geological mapping, rock geochemistry, petrographic studies, and
radiometric surveys covering a large area that encompasses the current Bear Lodge
Project area. M.H. Staatz of the USGS documented results of the work in
Professional Paper 1049D, entitled “Geology and Description of Thorium and Rare
Earth Deposits in the Southern Bear Lodge Mountains, Northeastern Wyoming” in
1983. The report concludes that “the Bear Lodge disseminated deposits have one of
the largest resources of both total rare earths and thorium in the United States”.
Hecla acquired a land position in the district in 1986 and added to it in 1988 by
optioning additional claims. Hecla discovered high-grade REE mineralization and
concentrated on rare earth exploration until the end of the 1990 field season, at which
time rare earth prices were falling. Hecla then acquired Coca Mines, which controlled
an adjacent property that hosted a small gold discovery. Following the Coca
acquisition in 1991, Hecla focused on the low-grade gold potential of the merged
property position. Hecla completed 12 diamond drill holes for 13,756 feet (4,194
meters) during its REE exploration phase and defined rare earth mineralization in
several carbonatite dike sets along the southwestern flank of Bull Hill. The dike sets
are part of the current Bull Hill REE deposit.
The USBM conducted work in the Bear Lodge Mountains to evaluate the REE
mineralization in the early 1950s, and again in 1990. In 1950, the USBM conducted
sampling that identified an REE-anomalous area defined by total REE abundances
greater than (>) 2000 ppm and drilled the anomalous area (mostly Whitetail Ridge)
with 10 shallow core holes that ranged in depth from 23.5 to 220.1 feet (7.2 to 67.1
meters). The work was reviewed in 1990 and resulted in an estimate of potential REE
resources in the general Bull Hill area.
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