SUSTAINABLE – LOW IMPACT
SUSTAINABLE – LOW IMPACT
SUSTAINABLE – LOW IMPACT
Barkerville Gold Mines
The Company has amassed mineral tenures that include the entire core of the district. BGM’s properties encompass approximately 195,000 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 Colombia 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.
“BGM has developed and actively utilizes a systematic, scientific framework for successful mineral exploration and resource development. Validation of this methodology is clearly demonstrated again and again with our drilling success.”Terry Harbort PhD.
The Cariboo Gold Belt has attracted interest and investment to south-central British Colombia 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 Company has amassed mineral tenures that include the entire core of the district. BGM’s properties encompass approximately 195,000 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.
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 Cow Mountain 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.
Mid Neoproterozoic 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.
The Bonanza Ledge Mine at Barkerville Mountain is BGM’s initial production unit. On April 23rd, 2015 BGM announced the completion of Phase I test mining via open pit, with 91,234 tonnes processed at a head grade of 8.66 grams per tonne, yielding 23,726 ounces and a total recovery of 93.4 %.
A new underground mine at Bonanza Ledge was recently permitted (March 2017), which contains a measured and indicated resource of 684,900 tonnes at 7.21 grams per tonne and 158,800 ounces with 18,600 ounces in the inferred category. Bonanza Ledge is situated on the southwest flank of Barkerville Mountain, about two kilometers northwest of the historical Williams Creek, which yielded 85,000 oz of alluvial production. This mine is an underground operation and will focus initially for about three years on the remaining underground resources at both Bonanza Ledge and BC Vein with the potential to develop other deposits nearby on Barkerville Mountain utilizing the same infrastructure.
Bonanza Ledge contains disseminated gold mineralization in a calcareous siltstone while BC Vein is a typical fault hosted quartz pyrite vein hosted mineralization style BC Vein is open at depth and along strike. Further exploration is planned to follow up on several new targets on Barkerville Mountain in the KL Zone and on the 2016 acquired Williams Creek tenements, which will add to the BC Vein strike length.
Cow Mountain hosts the historical Cariboo Gold Quartz Mine which exploited primarily vertically dipping quartz vein mineralization. From 1933 to 1959 the mine is reported to have produced 1.68 million tonnes grading 0.37 ounces per tonne (621,000 total ounces of gold). Due to a lack of exploration the mine was closed because the Company could not replace mined ounces. Through continued exploration the Cariboo Gold Quartz Mine still holds great potential for discovery of high-grade ore.
Today, Cow Mountain has been subject to an extensive diamond drill program testing continuity and extension at depth. BGM has completed a shallow phase 1 drill program in order to increase confidence on historic resources and plans to incorporate a new resource on Cow in a property wide resource statement in due course.
Aurum Mine (Island Mountain):
Gold rich sulphide replacement ore and vertically dipping gold-bearing quartz veins have been worked on Island Mountain since the early 1900s. Island Mountain is located immediately northwest of the Jack of Clubs Lake and just west of the town of Wells.
Island Mountain operated from 1934 to 1967, exploiting both vertically dipping quartz vein and replacement-style mineralization for a total reported production of 603,800 ounces of gold with an average grade of 0.45 ounces per tonne. Both Aurum and Mosquito Creek Mines focused on replacement style mineralization due to its higher grade and more coherent geometries. The mine closed in 1967 due to low metal prices.
The Aurum Mine, located at Island Mountain was developed on 11 levels to a vertical depth of ~300m via an internal shaft. Further development of the mine to the northwest was limited due to the historic boundary with the Mosquito Creek claim group, now owned by BGM. A later owner of the Aurum Mine developed extensions of the Island Mountain Mine into the Mosquito Creek claim group at a depth known as the Aurum Mine. Five levels were developed at Mosquito Creek over a strike length of over 1,000 feet between two prominent structures, the Burnett and Mosquito faults. The current drilling phase targets both fine-grained pyrite replacement and quartz vein styles of gold mineralization in large unexploited areas adjacent to past-producing gold mines.
Mosquito Creek (Island Mountain):
Island Mountain also hosts the Mosquito Creek Gold Mine, a small historic mine located 750 feet above the upper workings of the Aurum Mine. The mine was developed by Mosquito Creek Gold Mines Ltd. and operated from 1980 to 1987 producing 23,000 oz of gold. Again, the Company focused on replacement mineralization, leaving behind most of the vertically dipping quartz vein ore.
Underground development included a vertical shaft to a depth of 516 feet and levels at elevations of 4,400, 4,300, 4,200, and 4,100 feet. Following this early work by Mosquito Creek Gold Mines, a number of joint ventures saw additional underground development and exploration work carried out on the property.
Parallel to the focused resource definition underway in the Island Mountain-Cow Mountain-Barkerville Mountain corridor, BGM is developing a robust project pipeline through systematic greenfields exploration across our extensive package of mineral claims. Based on advanced multi-thematic targeting, regional exploration follows a systematic phase methodology implemented by our experienced team.
High-resolution soil sampling and reconnaissance over the last two years have delineated numerous high quality targets ready for drill testing. Continual detailed mapping of forestry roads and clear cuts adds to the regional geological mapping database of lithology, alteration and structure providing a quality base for future exploration.