The Mount Copeland deposit lies within metamorphic rocks flanking the southern margin of Frenchman Cap Dome. The Frenchman Cap Dome is one of a series of gneiss domes that occur along the eastern border of the Precambrian-Paleozoic(?) Shuswap Metamorphic Complex which is a narrow belt of high-grade metamorphic rocks in the Columbian orogen of southeastern British Columbia. This dome, which is centred 32 kilometres northwest of Revelstoke, has a core zone of migmatite and a fringing zone of metasedimentary rocks.
The metasedimentary rocks comprise a series of mappable units of biotite schist and grey schist, white quartzite, calc-silicate gneiss and marble, and grey gneiss. Concordant bodies of nepheline syenite gneiss occur with the calc-silicate gneiss and marble unit. Field, petrographic, and to a lesser extent, chemical evidence suggests the syenitic gneisses were emplaced as sills, and that these sills were emplaced before Shuswap deformation and metamorphism (Fyles, 1970; McMillan, 1974). The margins of the syenite bodies are nepheline-free, which may be the result of reaction with enclosing rocks.
The rocks have been metamorphosed and subjected to three phases of deformation. The oldest folds are recumbent and isoclinal with deformed axial surfaces and shallow easterly or westerly plunging axes. Second phase folds have overturned axial surfaces which dip steeply to the southwest and south. The broad curvature of the foliation around the southwest corner of the dome is referred to as a phase 3-fold.
Lenses of syenite pegmatite or syenite aplite are common along the northern border of the nepheline syenite unit and, because of their concentrations of molybdenite, are the focus of economic interest. Characteristically they lie parallel to foliation but they cross it locally. Massive disseminated molybdenite occurs randomly in the aplite and pegmatite lenses and to a lesser extent in calc-silicate gneisses adjacent to the syenite gneiss contact. During the life of the Mount Copeland mine, almost all production was from these aplite-pegmatite bodies within the syenite gneisses; more specifically the Glacier zone, which is up to 3 metres thick and exposed for 121 metres along strike.
The Glacier zone occurs in a digitation which is either a fold limb or a sill of syenite gneiss in the calc-silicate gneiss unit. In this digitation, the syenite gneiss appears to be free of nepheline. Calcite is commonly present in small amounts and locally is prominent in the syenite gneiss. Minor constituents of the rock include zircon, sphene, apatite and magnetite. Some samples also contain fluorite, some pyrite and/or pyrrhotite, and some molybdenite. The lens has been folded into tightly compressed, overturned (phase 2) folds (Fyles, 1970) that plunge 15 degrees southeastward. The axial surfaces of the folds dip at moderate angles towards the south. In detail, the aplite-pegmatite zones are irregular and molybdenite distribution is highly variable. Contacts between the aplites, pegmatites, and syenites may be either sharp or gradational.
The pegmatites and aplites have similar mineralogies. Both are leucocratic relative to the enclosing gneisses but both have local mafic-rich folia and lenses. Potassium feldspar is the dominant mineral. Locally the pegmatite matrix consists of masses of calcite that contain clusters of biotite, pyrrhotite, pyrite and ilmenite. Minor amounts of zircon are present; quartz is rare but occurs interstitially or as vug fillings. The oxide minerals, magnetite and ilmenite, are fairly common and locally form equant blobs up to 2 centimetres across. Sulphide minerals present include pyrite, pyrrhotite, molybdenite, and rare chalcopyrite. Sulphides fill cracks in the oxide minerals and apparently post-date them.
Molybdenite has a number of habits; it may be disseminated, form clumps and rosettes of crystals along hairline cracks, fill vugs, or occur as intergrowths with calcite, sericite, and potassium feldspar. Large crystals of molybdenite contain inclusions of potassium feldspar, calcite and zircon. However, molybdenite also occurs in potassium feldspar crystals and commonly is concentrated around potassium feldspar megacrysts in the pegmatites. Pyrrhotite and pyrite are also distributed as disseminations, fracture fillings, and line or fill vugs.
In the syenite gneisses, feldspars are clouded by kaolinite alteration or stained pink by sericite-calcite alteration. Biotite is locally chloritized. The pegmatite-aplite zones are similarly altered. Epidote and chlorite coat late-stage fractures in the rocks. Veinlets commonly consist of calcite, potassium feldspar, chlorite, or rarely, quartz.
Molybdenite showings on the north flank of Copeland Ridge were discovered in 1964. Underground exploration commenced in September 1967. A decision to go into production was made in 1969 and installation of a 180-tonne-per-day crusher and concentrator was completed in February 1970. Development work was underway simultaneously and production officially began on July 1, 1970. At that time, reserves were 163 278 tonnes grading 1.09 per cent molybdenum (Geology, Exploration and Mining in British Columbia, 1973). Production ceased in July 1974 and the mine was officially closed in October 1974.
The Mt. Copeland property was dormant from 1974 until 1995.
In 1995, Discovery Consultants staked the Mt. Copeland claim and completed a rock sampling program to assess the industrial mineral potential of the nepheline syenite. Discovery Consultants let the claims lapse and no work was done between 1995 and 2005.
In 2005, Andris Kikauka entered into a joint-venture with John Kalmet, Grant Anderson and William Pfaffenberger. Andris Kikauka then executed geological mapping, soil sampling and rock chip sampling at Mt. Copeland. Highlights include rock chip sample Cope-05 AR-7, which assayed 2.699 per cent molybdenum (Assessment Report 27908).
In 2007, Andris Kikauka conducted an exploration program of rock chip sampling. Highlights include sample VC090707-2, which assayed 3.6 per cent molybdenum over 0.4 metres (Assessment Report 29539).
In 2008, Torch River Resources Ltd. completed an exploration program of soil sampling, geophysical magnetometer surveys and 2212.8 metres of diamond drilling. The best intersection was a 2.7 metre section assaying 0.214 per cent molybdenum in drillhole COP08-09 (Assessment Report 30385).
In 2010, Torch River Resources Ltd. completed rock and soil sampling on the Mt. Copeland property. Highlights include sample COPE10AR-20, which assayed 131 000 grams per tonne cerium, 102 000 grams per tonne lanthanum, 17 650 grams per tonne neodymium, 7700 grams per tonne praseodymium, 6190 grams per tonne zirconium, 623 grams per tonne yttrium, 527 grams per tonne niobium, 284 grams per tonne dysprosium, 1200 grams per tonne samarium and 2.926 per cent titanium (Assessment Report 31834).
In 2011, Torch River Resources Ltd. extracted 48 rock chip samples from Mt. Copeland. Highlights include sample 832, which assayed 6100 grams per tonne cerium, 5780 grams per tonne lanthanum, 969 grams per tonne neodymium, 405 grams per tonne praseodymium, 104.5 grams per tonne samarium, 87 grams per tonne dysprosium, 712 grams per tonne yttrium, 145 grams per tonne zirconium, 0.0589 per cent molybdenum and 88.2 grams per tonne niobium (Press Release, Torch River Resources Ltd., January 11, 2012).