The Company has amassed mineral tenures that include the entire core of the district. BGM's properties encompass approximately 182,222 hectares across a belt that is 67 kilometers long by 25 kilometers wide. The area includes 101 creeks that have reported placer gold production and five past producing mines.The Cariboo Gold
Belt has attracted interest and investment to south-central British Columbia
since the famed Cariboo Gold Rush of 1861. That history lives on in the many heritage
sites and museums that dot the landscape today. Based upon historic estimates,
gold production in the Cariboo area was approximately 3.2 million ounces from
alluvial production and 1.3 million ounces from lode mines. The area includes 101 creeks that have reported placer gold production.
Historically Mined Ore
Analysis of the
Cariboo district's historical mining record, undertaken by BGM, implies a
strong possibility that the area will continue to yield gold-containing ore
over the long-term. Three mines are particularly notable in this regard:
Mosquito Creek and Aurum local to Island Mountain, and Cariboo Gold Quartz
found on Cow Mountain. Gold has predominantly been extracted from pyrite replacement
ore from Mosquito Creek, while at Mosquito Creek quartz vein ore was mined.
Approximately equidistant between them, the Aurum Mine split its yield between both
pyrite replacement and quartz vein ore. BGM believes that an even distribution
of both these gold-containing ores exists across the range, but has been
historically underexploited and the controls of mineralization poorly
understood until now. The Company therefore will look to target these areas, as
well as adjacent unexplored zones for potentially lucrative zones of economic mineralization.
to early Permian continental slope rocks of the Barkerville Sub-Terrane host Barkerville’s
vein and gold-rich replacement mineralization. Accreted to the North American
Craton in the Jurassic, the Barkerville Sub-Terrane is analogous to the
adjacent Cariboo Sub-Terrane and together compose the northern extension of the
Kootenay Terrane. The western Barkerville and eastern Cariboo terranes are
juxtaposed by the NNW trending westerly directed Pleasant Valley Thrust placing
the Cariboo on top of the Barkerville. The western margin of the Barkerville
Sub-Terrane is bounded by the easterly-directed Eureka Thrust, which places
island arc volcanic rocks of the Quesnel Terrane over the Barkerville Terrane.
Flat lying erosional remnants of the Quesnel Terrane overly the Barkerville
Terrane and have been called by previous workers the Slide Mountain Terrane
with the Eureka thrust called the Pundata Thrust. Within the Barkerville
Sub-Terrane, the Snowshoe Group is a package of predominantly arenaceous
siliciclastic rocks with intercalations of carbonaceous, calcareous and
metavolcanic rocks with local lenses of limestone. Arenaceous sandstones are
the preferred host for the gold bearing vein deposits, whereas the calcareous
sandstones and siltstones are hosts to the replacement mineralization.
ALTERATION AND MINERALIZATION
Mineralization is exhibited in numerous styles:
- Fault fill veins sub-parallel to lithology hosted in carbonaceous mudstone
- Vertical NE trending extensional veins dominantly hosted by sandstone units
- Moderately dipping ENE trending shear veins hosted in sandstone units
- Gold bearing sulphide replacement mineralization hosted in fold hinges of calcareous sandstone units
- Gold bearing sulphide replacement mineralization hosted in calcareous siltstone units bounded by fault structures
Sub-layer parallel faults form within the carbonaceous units develop sheared graphitic horizons, which, during metamorphism develop lenses of metamorphic quartz within layer parallel dilation zones. Once exhumed into a brittle environment these lenses are tectonically brecciated and infilled with gold and sulphide deposited in the breccia matrix with cryptocrystaline grey quartz.
Tectonostratigraphic facies can be mapped for tens for kilometers within the Company’s property. The lithologies have direct implications on mineralization styles within the camp with quartz veins preferentially developing in the thick sandstone units and replacement style mineralisation developing in calcareous horizons.
The BC fault structure is a long-lived structure interpreted as a major up flow zone that can be mapped for 1.2 kilometers along Barkerville Mountain. The fault structure is hosted in graphitic mudstone with accumulations of layer-parallel dilatational metamorphic lenses of quartz. The structure has been uplifted into a brittle environment, and continues strike slip movement brecciates the quartz lenses and surround country rock. A later hydrothermal event deposits silica and gold bearing pyrite within the matrix of the breccia.
Shear veins are present throughout the property, observed as shallow dipping tabular bodies. Interpreted to have formed in a brittle-ductile environment, these veins are generally barren except where they have been fractured, brecciated and mineralized in proximity to the later vertical veins discussed below. These veins are cemented with the gold bearing silica-pyrite mineralization.
From cross-cutting relationships with the other minerlaisation the vertical vein set is interpreted to be the latest vein set. Again, these veins prefer more robust lithological units that fracture during deformation. These veins are the main host for mineralization on Cow and Island Mountains, and the newly discovered KL Zone on Barkerville Mountain.
Replacement mineralization is local to calcareous bearing rocks that are found within the Bonanza Ledge ore body and Island Mountain. Vertical veins are interpreted from field observations to be the conduit for replacement mineralization of Island Mountain and the BC fault structure is the conduit for Bonanza Ledge ore body.
The alteration for all styles of deposits is consistent throughout the property, although mineralization does vary. Alteration consists of a silica-pyrite with minor sericite core, zoning outwards to a dominant sericite assemblage with minor silica and pyrite, pyrrhotite sphalerite. Fe-Carbonate is ubiquitous throughout the alteration sequence. Cosalite correlates with higher gold values often associated with visible gold occurrences., where galena is associated with high silver grades.