Banks Island lies along the western edge of the Tertiary-Jurassic Coast Plutonic Complex characterized by northwest-trending granitic bodies, mainly granodiorite-quartz monzonite and quartz diorite, which are separated by narrow, persistent Permian(?) or older metasedimentary belts, mainly crystalline limestone, micaceous quartzite skarn and schist. The metasedimentary rocks generally exhibit a wide range of ‘granitization’ effects and contact metasomatism. Regional and local faulting, fracturing and folding are common on the island. Two major right-lateral faults striking 310 degrees, known as the Arseno and Hepler faults, have associated 045 degree linears. Left-lateral faults striking 090 degrees also occur. Many contacts between the plutonic and metasedimentary rocks are faults or drag folds. Some faults have been healed by recrystallization. Structure is the prime factor in ore localization.
The Discovery zone is localized within a northwest-trending fault zone that partially crosscuts metasedimentary rocks parallel to the margin of altered biotite quartz monzonite. The mineralized zone occurs between coarsely crystalline grey marble to the south and zoisite-actinolite-quartz skarn to the north. The metasediments are cut by hornblende-quartz diorite dikes. The fault structure strikes 315 to 320 degrees and dips steeply (80 degrees) northeast. The mineralization dips less steeply near surface (55 to 65 degrees northeast). Sulphide mineralization consists of pyrite, pyrrhotite, arsenopyrite, sphalerite and chalcopyrite, which replace the grey marble and brecciated skarn.
The mineralized zone averages 3 metres wide and is up to 76 metres long and 90 metres in vertical depth. The deposit appears to be a 30 degree southeast-plunging shoot, open at depth and strike length.
The Discovery zone was discovered in 1960 during prospecting by Falconbridge Nickel Mines Ltd.
In 1963, Falconbridge Nickel Mines Ltd. completed geochemical and geophysical surveys and 14 diamond drillholes. Anomalous gold, silver, copper, zinc and lead were found in the drillcores.
In 1976, Falconbridge Nickel Mines Ltd. completed 1130.2 metres of diamond drilling on the Yellow Giant property.
In 1984, Trader Mines Ltd. completed limited geophysical surveys and diamond drilling on the Discovery zone. A 15.2-metre drill intersection assayed 24.69 grams per tonne gold and 63.77 grams per tonne silver (Assessment Report 14171).
In 1988, unclassified reserves for the Discovery zone were 58 361 tonnes grading 15.5 grams per tonne gold (Trader Resource Corp., Letter to Shareholders, March 28, 1988).
In 1993, Trader Resources Corp. owned 90 per cent of the Yellow Giant property claims, while Falconbridge Nickel Mines Ltd. owned the remaining 10 per cent of the claims.
In 1994, Trader Resources Corp. was renamed Highwood Resources Ltd.
In 1996, Energex Minerals Ltd. acquired 51 per cent of the claims from Highwood Resources Ltd.
In 1998, Doublestar Resources Ltd. acquired the 51 per cent share held by Energex Minerals Ltd.
In 2000, Doublestar Resources Ltd. acquired Falconbridge Nickel Mines Ltd.’s 10 per cent stake of the claims.
In 2002, Dynatec Corp. merged with Highwood Resources Ltd. to form Beta Minerals Inc.
In 2007, Selkirk Metals Corp. acquired 61 per cent of the Yellow Giant property claims through the purchase of Doublestar Resources Ltd.
In 2009, Advanced Primary Minerals Corp. acquired 39 per cent of the claims through the reverse takeover of Beta Minerals Inc. and then sold the stake to Selkirk Metals Corp., giving them 100 per cent ownership of the property. Imperial Metals Corp. then acquired all the shares of Selkirk Metals Corp., making it a wholly-owned subsidiary of Imperial Metals Corp.
No exploration work was completed on the property from 1988 until 2010, when Selkirk Metals Corp. completed a control survey to establish UTM coordinates for old drillholes and facilities.
In 2011, Banks Island Gold Ltd. optioned the property from Selkirk Metals Corp.
In 2012, Banks Island Gold Ltd. completed 12 diamond drillholes in the Discovery zone. Highlights include drillhole DIS-12-03, which returned 3.7 metres (estimated true width of 2.6 metres) grading 135.5 grams per tonne gold and 48 grams per tonne silver (Press Release, Banks Island Gold Ltd., May 25, 2012). Banks Island Gold Ltd. released a NI 43-101 compliant mineral resources estimate for the Discovery zone which showed a measured resource of 10 000 tonnes grading 22.1 grams per tonne gold and 36 grams per tonnes silver, an indicated resource of 15 000 tonnes grading 22.8 grams per tonne gold and 36 grams per tonne silver and an inferred resource of 6000 tonnes grading 30.8 grams per tonne gold and 36 grams per tonne silver using a 6 gram per tonne gold cut off (Press Release, Banks Island Gold Ltd., October 22, 2012).
See Kim (103G 021), Bob (103G 024) and Tel (103G 026) showings for additional information and resource estimates.