The Chief occurrence is located 5.5 kilometres southeast of Glossy Mountain, 18 kilometres west of Tunkwa Lake.
The area lies at the northern boundary of the Upper Triassic to Lower Jurassic Guichon Creek Batholith. The batholith is a composite, calc-alkaline intrusion consisting of granodiorite and granite, with diorite and quartz diorite common as border phases. Upper Triassic rocks of the Nicola Group envelop the batholith and locally form roof pendants. The Jurassic Ashcroft Formation unconformably overlies the Nicola Group and batholith. The Eocene Kamloops Group unconformably covers the older rocks along the north end of the batholith.
Between Brassy and Rattlesnake creeks, Nicola Group andesitic and basaltic flows and tuffs have been intruded by multiphase intrusive bodies that are correlated with the Guichon Creek Batholith. The predominant plutonic lithology is a hornblende diorite. Quartz syenite-quartz monzonite and associated intrusive breccia and a small quartz porphyry (rhyolite?) plug have intruded the hornblende diorite and are exposed along Rattlesnake Creek. In this vicinity a prominent gossan has formed due to weathering of heavily pyritized and silicified quartz porphyry and hornblende diorite. The intrusive breccia contains disseminated chalcopyrite and was the target of a 1976 percussion drilling program by BP Minerals Ltd.
Exploration in 1984 uncovered a quartz-carbonate stockwork that is exposed for approximately 7 metres in altered hornblende diorite; gold values range up to 0.780 grams per tonne. Alteration consists of intense carbonate-silica and quartz-pyrite veining.
A select sample of diorite with malachite stains along fractures taken in 1996 assayed 0.49 per cent copper and 9 grams per tonne silver (Assessment Report 24809).
Work History
Previous work, in 1970 and 1971, on the Geo claims (now called Brassie Creek [MINFILE 092INW018] and which adjoined the Chief claims) consisted of a very low frequency electromagnetic survey, induced polarization survey, geological mapping, three diamond drill holes, totalling 230 metres, and a ground magnetometer survey on behalf of Supertest Investments and Petroleum Ltd. BP Minerals diamond-drilled six holes in 1973 but no report was filed. Between the period 1974 to 1987, work on the Chief property, on behalf of Bethlehem Copper Corporation, BP Minerals Limited, Ninja Resources Ltd., MineQuest Exploration Associates Ltd. and QPX Minerals Inc., consisted of ground and/or airborne electromagnetic and magnetic surveys, induced polarization surveys, percussion drilling, soil geochemistry and geological mapping.
In 1999, Christopher James Gold Corp. completed a drilling and rock sampling program on the Brassie Creek property. Three drillholes, totalling 324.6 metres, were completed and 141 core samples were submitted for assay. A total of 82 rock samples were collected and submitted for assay.
In 2013, K. Ellerbeck completed a program of prospecting and rock sample on the Brassie claim group near the Chief occurrence area. In total 11 grab samples were collected, 4 of which were submitted for assay.
In 2015, K. Ellerbeck collected 12 grab samples as part of a prospecting program on the Brassie claim group; three of the grab samples were assayed
In 2017, K. Ellerbeck completed a program of prospecting and rock sampling on the Brassie claim group; four rock samples were collected and assayed.