Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
th
, 2014
10135-200-46 - Rev. 0
14-15
Table 14.8 - Apparent TREO Grade Bias for Low- and
High-Core-Recovery Samples
Grade
Range
Oxidation
Type
Low Recovery
(0-95%)
High Recovery
(>95%)
All Samples
Apparent
Bias
Relative to
Low-
Recovery
Samples
Apparent
Bias
Relative to
All Samples
Footage Meters Average
TREO
Footage Meters Average
TREO
Footage Meters Average
TREO
<30%
FMR
Oxide
64,399
19611
0.838
37,257
11356
0.770
101,656 30985
0.813
9%
3%
OxCa
23,246
7085
0.817
13,455
4101
0.695
36,701
11186
0.772
18%
6%
Ox+OxC
a
87,646
26715
0.833
50,712
15457
0.750
138,358 42172
0.802
11%
4%
>30%
FMR
Oxide
7,636
2327
3.953
3,440
1049
4.504
11,076
3376
4.124
-12%
-4%
OxCa
5,662
1726
3.840
2,403
732
4.239
8,064
2458
3.959
-9%
-3%
Ox+OxC
a
13,297
4053
3.905
5,843
1781
4.395
19,140
5834
4.054
-11%
-4%
All
Sampl
es
Oxide
72,035
21956
1.169
40,698
12405
1.085
112,732 34361
1.138
8%
3%
OxCa
28,908
8811
1.409
15,857
4833
1.232
44,766
13645
1.346
14%
5%
Ox+OxC
a
100,943 30767
1.237
56,555
17238
1.126
157,498 48005
1.197
10%
3%
(A.Noble, 2014)
14.7 Compositing
Given the highly variable orientation of drill holes with respect to the REE dikes, a
method was developed to composite drill-hole samples into widths that approximate
the horizontal true width of the veins. In addition, the composites were optimized to
provide composite intervals that were above a specified cutoff grade and longer than
a specified minimum width. There were two objectives for this procedure: first, the
resulting composites should partition into low-grade and high-grade populations
representing stockwork-dominant and dike-dominant mineralization, and second, the
composites should have sufficient width to provide geometric dilution for a reasonable
minimum mining width.
True width compositing was done using parameters specific to each estimation
domain, as summarized in Table 14.9 and using the algorithm outlined in Table
14.10. Width and cutoff parameters were developed heuristically to provide
subpopulations of low-grade and high-grade composites that were as close to
lognormal populations as possible, subject to a minimum mining width of at least 20
feet.
