NI43-101Pre-Feasibility Study Report - page 155

Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
, 2014
10135-200-46 – Rev. 0
November) drill programs. A Maxidrill 10-C was brought in as a fourth drill during the
second half of the 2011 drill program. The 2012 program employed two skid-
mounted LF-70 drills, the track-mounted Maxidrill 10-C, and a skid-mounted CS-1000
rig. The 2013 drilling program was conducted by Major Drilling of Salt Lake City, Utah
and utilized a track-mounted Longyear LF-70 and a track-mounted Longyear LF-90
core drilling rigs, and a track-mounted Schramm T-450GT RC drill rig.
In general the holes were drilled with HQ-sized core (77.8 mm inside diameter).
During the 2004 through 2008 drill programs (12 holes total), HQ core was drilled
through the oxidation zone (to approximate depths of 300 to 500 feet/90 to 150 m),
after which core size was generally reduced to NQ (60.3 mm inside diameter). In
2007, two drill holes (RES07-1 and RES07-2) were drilled deeper with HQ core
before reducing to NQ in order to secure a larger sample for metallurgical testing. In
2008, one hole (RES08-4) was reduced from HQ to NQ at about 300 feet (90 m), and
then from NQ to BQ (46.1 mm diameter) at about 1,400 feet (425 m) depth. BQ core
was drilled to the end of the hole (1,886 feet/575 m). From 2009 through 2012 most
holes were drilled with HQ-sized core, with the exception of 15 holes that were
reduced to NQ prior to the end of the hole. One hole (RES10-57) was drilled with PQ-
sized core (85 mm diameter) through the top several hundred feet to address
anticipated recovery problems associated with broken ground. Initial use of the larger
diameter PQ core provided additional opportunities to reduce in the event of adverse
down-hole drilling conditions. The core was reduced to HQ-sized core, and then to
NQ-sized core several hundred feet from the end of the hole (1,675 feet; 510 m).
In 2013 HQ-sized core was used for the Whitetail Ridge infill drilling and PQ-sized
core for the Bull Hill high-grade infill drilling.
10.3.2 Recovery and Rock Quality
The un-oxidized carbonatite dikes, along with FMR and OxCa veins and dikes, the
near-surface oxidized equivalents of the carbonatite dikes, were the target of most
drilling completed in the Bull Hill area through 2008. From 2004 through 2008, core
recovery in the friable, leached, and weathered FMR zones was generally much lower
than in the more competent OxCa and sulfide-bearing carbonatite rocks, with a range
from 0 to 100% and an average recovery of slightly better than 70 percent. The low
recoveries are due primarily to the presence of the variably leached and fractured
FMR dikes, veins, and stockwork, which tend to fracture and disaggregate easily
during the drilling process. The zones may also contain void space that also reduces
recoveries. The void space results from dissolution of matrix carbonate in the original
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