Rare Element Resources
Bear Lodge Project
Canadian NI 43-101 Technical Report
October 9
th
, 2014
10135-200-46 – Rev. 0
8-7
Table 8.2 - Thorium & Uranium-Bearing Mineral Phases Associated
with the Bear Lodge REE Deposit
Mineral Phase
Formula
Occurrence
Importance
Monazite
(Ce,La,Nd,Th)PO
4
Variable distribution in
REE-mineralized dikes
and
veins.
May
constitute up to 1/3 of
REE minerals locally, but
generally
minor
abundance.
High
(May contain multiple percent Th
and minor U)
Thorianite and
Thorite
ThO
2
and ThSiO4
Variable distribution in
REE-mineralized dikes
and veins.
Low to
Moderate
(Primary Th minerals)
Pyrochlore
(betafite)
(Ca, U)
2
(Ti, Nb, Ta)
2O6
(OH)
Identified tentatively as
trace
accessory
in
oxidized
REE
mineralized dikes and
veins.
Low
Uranpyrochlore
(U,Ca,Ce)
2
(Nb,Ta)
2
O
6
(OH,F)
Trace accessory in host
rocks.
Low
Britholite
(Ce,Ca,Th,La,Nd)
5
(SiO
4
,PO
4
)
3
(OH,F)
Trace accessory noted in
some gold-bearing veins
outside zone of REE
mineralization.
Low
(A. Noble, 2014)
Minor amounts of thorium and uranium may also be present in the primary REE
minerals, the REE fluocarbonates (bastnasite, parisite, and synchysite) and ancylite
(hydrous Sr-REE carbonate), but thorium and uranium do not appear in the literature
as essential components of these phases. Thorium abundances appear to be higher
in bastnasite group minerals and monazite from the Whitetail Ridge resource area
and from the Taylor and Carbon exploration target areas. Average thorium and
uranium abundances of the bastnasite group minerals and ancylite from the Bull Hill
deposit, based on electron microprobe analyses conducted by the Company in 2006,
are presented in Table 8.3.
