The Mona-Westholme occurrence is located on the southwest slope of Mount Sicker, approximately 5.5 kilometres west-southwest of Westholme. The Richard III (MINFILE 092B 003) occurrence is located approximately 500 metres to the west. The Westholme shaft is located on the Westholme Crown-granted claim near the southeast corner of the Estelle Crown-granted claim, while the Mona shaft is located approximately 160 metres to the northwest on the Mona Crown-granted claim and near its border with the Estelle Crown-granted claim.
Regionally, the area is located within the Cowichan uplift and is underlain by andesitic to rhyolitic volcanics of the Middle to Upper Devonian McLaughlin Ridge and Myra Formations (Sicker Group). The local stratigraphy is disrupted by folding, faulting (pre-Triassic as well as Paleogene–Neogene), intrusions of gabbro and diabase sills and dikes (known as the Mount Hall gabbro) that are coeval with the Upper Triassic Karmutsen Formation (Vancouver Group).
Locally, chalcopyrite and pyrite mineralization is hosted by volcanic rocks exposed in a tailings pile and old shaft. Approximately 100 metres east of the Mona shaft a mineralized zone is exposed for approximately 20 metres and is up to 11 metres wide. Mineralization is comprised of abundant pyrite and chalcopyrite stringers and veins up to 30-centimetres in width.
In 1986, drillhole MTS-27, located between the Westholme and Mona shafts, was drilled to test an interpreted east continuation of the Lenora-Tyee mine horizon across the Fortuna faults and below the Mona diorite. Fine sphalerite stringers were encountered below the diorite within barium enriched, weakly sericitized quartz-crystal tuffs and yielded intercepts including 0.21 per cent zinc over 1.2 metres at 41.95 metres down hole and 5.70 per cent zinc with 0.33 per cent copper over 0.07 metre at 52.42 metres down hole (Assessment Report 15719).
In 1987, drillhole MTS-38, located east of the Westholme shaft, yielded intercepts of up to 0.37 per cent zinc with 0.14 gram per tonne gold over 1.00 metre (73.10 to 74.10 metres down hole) from a felsic ash with chert fragments and beds hosting pyrite and trace chalcopyrite in veinlets, and drillhole MTS-43, located west-southwest of the Mona shaft, yielded intercepts including 1.29 per cent copper, 10.4 grams per tonne silver and 0.18 gram per tonne gold over 0.60 metre (130.50 to 131.10 metres down hole) and 0.67 per cent copper over 0.80 metre (133.40 to 134.20 metres down hole) in a felspar phyric crystal tuff/ash hosting semi-massive pyrite and chalcopyrite stringers (Assessment Report 16716).
In 1989, drillhole MTS-63, located several hundred metres east-southeast of the Westholme shaft yielded 0.49 per cent copper and 5.8 grams per tonne silver over 0.5 metre (277.40 to 277.90 metres down hole) in intermediate tuff, ash, lithic tuff and chert hosting quartz veins with pyrite and minor chalcopyrite (Assessment Report 18520).
Also at this time, drillhole MTS-64, located on the Nellena claim and approximately 650 metres southeast of the Westholme shaft, yielded intercepts including: 0.136 per cent copper with 0.465 per cent zinc over 0.20 metre (197.70 to 197.90 metres down hole) and 0.700 per cent zinc over 0.55 metre (320.70 to 321.25 metres down hole), and drillhole MTS-65, located several hundred metres east of the Mona shaft, yielded intercepts including 2.96 per cent copper, 9.0 grams per tonne silver and 0.13 gram per tonne gold over 0.40 metre (329.40 to 329.80 metres down hole) and 0.16 per cent copper, 0.49 per cent zinc, 6.0 grams per tonne silver and 0.14 gram per tonne gold with 0.26 per cent barium over 0.80 metre (423.10 to 423.90 metres down hole; Assessment Report 18859).
In 2020, two samples (S47 and S48) from the Mona shaft dump yielded 0.19 and 1.80 per cent copper, 0.23 and 12.32 per cent zinc with 0.09 and 0.94 per cent lead, and two samples (S49 and S50) from the Westholme shaft dump yielded 6.65 and 14.18 per cent copper, 0.09 and 0.12 per cent zinc with 0.02 and 0.07 per cent lead (Portable-XRF assay; Assessment Report 39405). Also at this time, two dump samples (S51 and S52) from the Blubell shaft yielded 0.34 and 1.13 per cent copper with 0.22 and 0.03 per cent zinc (Portable-XRF assay; Assessment Report 39405).
In 2021, three samples (one outcrop and two float) from the Mona and Westholme occurrence area yielded from 0.91 to 2.90 per cent copper, 0.01 to 0.57 per cent lead, 0.03 to 6.73 per cent zinc, 16 to 50 grams per tonne silver and 0.43 to 1.40 grams per tonne gold (Assessment Report 40298).
Work History
Three historical shafts, referred to as the Westholme, Mona and Bluebell shafts, are reported in the occurrence area and likely date to the late 1890s or early 1900s. The Bluebell shaft is located approximately 350 metres north of the Westholme shaft, and the Mona shaft is located roughly between the previous two shafts. The Westholme shaft is reported to be approximately 200 metres long, whereas the Mona shaft has been developed for approximately 40 metres and the Bluebell shaft is at least 7 metres deep. The area has been historically explored in conjunction with the nearby Richard III (MINFILE 092B 003) occurrence and a complete early history of the Mount Sicker area can be found there.
During 1964 through 1966, the area was held and explored by Mt. Sicker Mines Ltd. In 1967, Mt. Sicker Mines conducted a geological mapping program of on the Field and South Groups of the Mt. Sicker property. In 1972, Duncanex Resources conducted a program of line-cutting on the area.
In 1972, Duncanex Resources completed a program of prospecting, geological mapping and a 34.0 line-kilometre ground electromagnetic survey on the surrounding area as the CF Group. In 1974, Dresser Ind. completed four diamond drill holes, totalling 830.0 metres, on the Lenora property. In 1977, John Deighton conducted a geological mapping program on the area as the Yankee, Margie and Mollie claims. During 1978 through 1980, S.E.R.E.M. Limited completed programs of geological mapping, ground geophysical surveys, soil sampling and seven diamond drill holes, totalling 1235.9 metres, on the surrounding area as the Rocky claims.
In 1985 and 1986, Falconbridge Copper completed programs of geological mapping, rock sampling, an induced polarization survey and a single diamond drill hole (MTS-27) on the area. The former dump and shaft were reported to correlate with a strong chargeability and resistivity anomaly.
In 1987, Minnova Inc. completed 16 diamond drill holes, totalling 3217.2 metres, on the Twin property. Three diamond drill holes (MTS-38, -41 and -43) were completed to test the extent of zinc mineralization in the Mona and Westholme shafts area.
During 1988 through 1990, Minnova completed programs of geochemical sampling and at least 11 diamond drill holes, totalling 3865.8 metres, on the area as the Mount Sicker property. At least five drillholes (MTS-61, -62, -63, -64 and -65) were completed on the Mona and Westholme shafts area.
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 2017, the area was prospected by Justin Deveault as the Hayden claim.
In 2020, 911 Mining Co. conducted a program of prospecting and geochemical (rock and silt) sampling on the area as the Mount Sicker property. 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.
