The Pillar showing, composed of finely disseminated bornite in a fine-grained feldspar porphyry over 4.58 metres width, is located 4.75 kilometres north of Toodoggone Lake and west of Jack Lee Creek. The showing is located in the south-central part of the Toodoggone gold camp, roughly 280 kilometres north of Smithers.
The showing is situated within a Mesozoic volcanic arc assemblage which lies along the eastern margin of the Intermontane Belt, a northwest-trending belt of Paleozoic to Tertiary sediments, volcanics and intrusions bounded to the east by the Omineca Belt and to the west and southwest by the Sustut and Bowser basins.
Permian Asitka Group crystalline limestones are the oldest rocks exposed in the region. They are commonly in thrust contact with Upper Triassic Takla Group andesite flows and pyroclastic rocks. Takla volcanics have been intruded by the granodiorite to quartz monzonite Black Lake Suite of Early Jurassic age and are in turn unconformably overlain by or faulted against Lower Jurassic calcalkaline volcanics of the Toodoggone Formation, Hazelton Group.
The dominant structures in the area are steeply dipping faults which define a prominent regional northwest structural fabric trending 140 to 170 degrees. In turn, high angle, northeast-striking faults (approximately 060 degrees) appear to truncate and displace northwest-striking faults. Collectively these faults form a boundary for variably rotated and tilted blocks underlain by monoclinal strata.
The Pillar showing is underlain by a 1.5 kilometre, subcircular hornblende syenite to monzonite stock of the Early Jurassic Black Lake Suite. This stock intrudes undivided volcanics of the Toodoggone Formation, which at this locality consist of feldspar porphyry, hornblende-quartz and hornblende-feldspar andesite (Assessment Report 1825).
Volcanic rocks are well fractured, but fracture patterns are obscure. The dominant set strikes west-northwest and dip 70 to 80 degrees northeast. Intrusive rocks exhibit two fracture orientations; 320 degrees and dipping 80 degrees northeast and 045 degrees and dipping vertical.
At the Pillar showing sparse chalcopyrite and associated malachite mineralization occur in northwest-oriented fractures, which have been exposed in three trenches over a total area of 15 by 183 metres and to a depth of 31 metres. The showing is coincident with a strong copper soil geochemical high of 350 to 1050 parts per million and a magnetic high of greater than 4000 gammas (Assessment Report 1825).
In 1968, a rock sample (PR-7) of fractured and sheared andesite with pyrite from a shear zone yielded 0.056 per cent copper and 5.0 grams per tonne silver (Property File - Cordilleran Engineering Ltd. (1968-08-28): Report on Follow-Up Geochemical Surveys in the Toodoggone River Area).
In 1969, a rock chip sample (2131) assayed 0.11 per cent copper, 0.15 per cent zinc and 3.0 grams per tonne silver (Property File - Cordilleran Engineering Ltd. (1969-08-11): Geochemical Lab Report and Sample Tags - No. 29-251 - Pillar Claim).
Work History
In 1968, Quebec Cartier Mines and Kennco Explorations Ltd. completed a program of geological mapping, soil sampling, trenching and a 53.0 line-kilometre ground magnetic survey on the area as the Pillar claims. Also, at this time and in 1969, Kennco Explorations Ltd. completed programs of rock and soil sampling on the area immediately southwest as the Pillar No. 1 and 2 groups.
In 1980 and 1981, Serem Ltd. completed programs of geological mapping, geochemical (rock, silt and soil) sampling and a ground electromagnetic survey on the area as the Jock 1-5 and Itsch claims.
In 1982 and 1983, Golden Rule Resources Ltd. completed programs of prospecting, geological mapping, geochemical (rock, silt and soil) sampling and airborne geophysical surveys on the area as the Jock 1-5 claims. In 1985, a further program of prospecting, geological mapping and rock sampling was completed on the Jock claims.
In 1986, the Toodoggone Syndicate completed a 75 line-kilometre airborne geophysical survey on the area immediately north as the Anna and Michel claims. Also at this time, Canasil Resources Inc. completed a program of geological mapping, geochemical (rock, silt and soil) sampling and a ground resistivity survey on the area and the Brenda and Jan claims located immediately to the south and east. In 1987, Beachview Resources Ltd. completed a program prospecting and geochemical (rock and soil) sampling on the Anna and Michel claims.
In 1988, Canasil Reseources completed a further program of rock and soil sampling, geological mapping and ground geophysical surveys were completed on the area as part of the Brenda property. During 1989 through 1993, programs of trenching and soil and rock sampling were completed on the area. During 1994 through 1997, further programs of diamond drilling were performed on the Brenda property, primarily on the Brenda - White Pass (MINFILE 094E 147) zone.
In 2002, Northgate Minerals Corporation optioned the Brenda property from Canasil Resources Inc. A high-resolution airborne magnetic, radiometric and satellite imaging surveys followed by 1650 metres of diamond drilling in four holes on the Brenda - White Pass (MINFILE 094E 147) zone. In 2003, a program of rock and soil sampling and five diamond drill holes, totalling 1481.1 metres, were completed on the Brenda property. In 2004, a further five diamond drill holes, totalling 1445.7 metres were completed. After review of the 2004 data, Northgate returned the property to the vendor.
In 2007, Canasil Resources conducted a 32.2 line-kilometre 3-D induced polarization survey and five bore holes, totalling 1708 metres, centred over the White Pass (MINFILE 094E 147) zone area.
In 2013, Canasil Resources Inc. completed a program of rock sampling and a lone drillhole, totalling 962.6 metres, on the Brenda property.
During the 1990s through 2020 (from 1999 by Finlay Minerals Ltd.) the area immediately north was explored as part of the Pil property, and a completed exploration history can be found at the Pil South (MINFILE 094E 310) occurrence.
