The Key City occurrence is located on the western slopes of Mount Sicker, approximately 1.2 kilometres east of the Chemainus River.
Regionally, the area is within the Cowichan uplift; one of three geo-anticlinal uplifts that expose Paleozoic Sicker and Buttle Lake Group rocks on Vancouver Island. Cretaceous sediments of the Nanaimo Group unconformably overlie the Paleozoic rocks; the contact is marked by a basal conglomerate containing volcanic fragments derived from the Sicker Group. The local stratigraphy is disrupted by folding, faulting (pre-Triassic as well as Paleogene–Neogene) and the intrusions of gabbro and diabase sills and dikes (known as the Mount Hall Gabbro) that are coeval with the Upper Triassic Karmutsen Formation.
The Sicker Group rocks mainly comprise felsic volcanic tuffs of the Middle to Upper Devonian McLaughlin Ridge Formation. The rocks in the area include graphitic schists and cherty sediments and tuffs which form a band within the rhyolitic volcanics. This is the same band of rock which hosts the massive sulphides on the Lenora-Tyee mines (MINFILE 092B 001) to the immediate east.
Locally, a historical adit and underground workings expose a schist hosting a small amount of pyrite and chalcopyrite show in small stringers or disseminations. Another shaft, referred to as the XL shaft is located near the northwest corner of the X.L. (L.19G) and northeast corner of the N.T. Fraction (L. 43G) Crown-granted claims and approximately 150 metres south-southwest of the Key City shaft.
Work History
The property was first explored, in the late 1890s or early 1900s, by an adit run from south to north for approximately 160 metres in order to intersect the projected extension of the Lenora orebody. Overall, the adit cuts approximately 60 metres of diorite and 100 metres of schist. A shaft runs 30 metres from the surface to intersect the adit approximately 100 metres from the portal. The shaft then continues down to the 60-metre level where a crosscut is made 60 metres to the south.
In 1967 and 1968, Mt. Sicker Mines conducted programs of geological mapping, a 48.0 line-kilometre ground electromagnetic survey and a 3.0 line-kilometre ground magnetic survey on the Mt. Sicker property.
In 1972, Duncanex Resources completed a program of prospecting, line-cutting, geological mapping and a 34.0 line-kilometre ground electromagnetic survey on the surrounding area as the CF Group and Dawn claims. In 1974, Dresser Ind. completed four diamond drill holes, totalling 830.0 metres, on the Lenora property. During 1978 through 1980, S.E.R.E.M. Limited completed programs of geological mapping, ground geophysical surveys and soil sampling on the Rocky claims.
In 1986, Falconbridge Copper completed a 23.3 line-kilometre induced polarization survey on the area. Also at this time, six diamond drill holes (MTS-18, -19, -20, -21, -22 and -23) were completed on the Key City, Tony and XL claims to test the faulted extension of the Lenora-Tyee Mine Package, west and south of the former works. Diamond drill hole MTS-18, located on the XL claim to the south, failed to intercept the ‘Mine Package’ series of rock but did yield 0.35 per cent zinc over 0.3 metre in stratigraphically lower units comprised of an interbedded succession of rhyodacitic ash, tuff, crystal tuff and minor andesite, whereas drillhole MTS-19, located a short distance southeast of the Key City shaft, yielded intercepts of 0.58, 0.37 and 0.32 per cent copper over 0.73, 0.45 and 0.30 metres and at depths of 13.00, 44.55 and 98.0 metres down hole, respectively (Assessment Report 15719). Also at this time holes (MTS-23 and MTS-20), located a short distance west of the Key Stone and XL shafts, respectively, yielded 0.35 and 0.35 per cent copper over 0.95 and 0.78 metres at 134.8 and 145.0 metres down hole, respectively (Assessment Report 15719).
During 1987 through 1990, Minnova completed programs of geochemical sampling and at least 27 diamond drill holes, totalling 7073.0 metres, on the area as the Mount Sicker and Twin properties. At least three holes (MTS-58, -59 and -60) were completed on the Key City claim. No significant intercepts were reported.
In 2008, Westridge Resources completed a 440.3 line-kilometre airborne geophysical (magnetic and electromagnetic) survey on the area as part of the Fortuna property. In 2010 and 2011, Rock-Con Resources completed a program of prospecting and rock sampling on the Mount Sicker property.
In 2013 and 2014, Conarry Ventures Inc. conducted programs of prospecting and rock sampling on the area as the Mount Sicker property. Two samples (E5123799 and E5123800) a quartz vein in rhyolite exposed in a road cut, located approximately 400 to the northwest of the plotted location of the Key City occurrence, assayed 1.32 and 1.15 grams per tonne gold, 3.8 and 62.8 grams per tonne silver, trace and 0.363 per cent lead, 0.02 and 10.48 per cent zinc with 1.06 and 1.37 per cent copper (Assessment Report 34604).
In 2020, 911 Mining Co. conducted a program of prospecting and geochemical (rock and silt) sampling on the area as the Mount Sicker property. A grab sample (S41) from the Key City shaft dump yielded 4.56 per cent copper, whereas two outcrop chip samples (S42 and S44) from the Key City adit area yielded 2.36 and 17.2 per cent copper, respectively (Portable-XRF assay; Assessment Report 39405). Also at this time, a chip sample from the X.L. shaft yielded 0.24 per cent copper (Portable-XRF assay; Assessment Report 39405).
In 2021 and 2022, Scenc Resources Corp. completed a minor program of geological mapping, rock sampling, a 1.8 line-kilometre ground electromagnetic survey and four backpack drill holes, totalling 14.9 metres, on the Mount Sicker property. Later in 2022, Sasquatch Resources Corp. completed a program of prospecting, geological mapping, drillcore and rock sampling and a 418.2 line-kilometre airborne electromagnetic survey on the Mount Sicker property.
