The Bay 21 (A zone) occurrence is located approximately 150 metres south of the southwestern end of Frances (Bay) Lake.

Regionally, the area is underlain by northwest-trending belts of basaltic volcanics and carbonate sedimentary rocks of the Upper Triassic Karmutsen and Quatsino formations (Vancouver Group) and mafic volcanics and sediments of the Upper Triassic to Lower Jurassic Bonanza Group (Holberg volcanic unit, Nahwitti River wacke and Parson Bay Formation). These volcanic and sedimentary rocks have been intruded by granodioritic rocks of the Early to Middle Jurassic Island Plutonic Suite.

Locally, at the A zone, discontinuous sections of ‘high-grade’ copper mineralization have been exposed by trenches and drillholes along a narrow, northerly trending zone where propylitic-altered andesite and lapilli to ash tuffs are laced with chalcopyrite, pyrite and magnetite in stringers up to 2.5 metres wide. The stringers trend 060 to 335 degrees in a zone trending 300 degrees and dipping 60 degrees north. The footwall, associated with a parallel fault, is intensely bleached and silicified with considerable disseminated pyrite and rare specks of chalcopyrite. Epidote, chlorite and sericite alteration is common.

Another zone of mineralization, located 270 metres southeast of the main trenches, consists of propylitized andesite and andesite tuff hosting chalcopyrite and pyrite over an area 15 metres wide and 45 metres long.

In 1965, channel samples from the two main trenches yielded 4.17 per cent copper, 34.3 grams per tonne silver and 0.34 grams per tonne gold over 1.4 metres and 3.37 per cent copper, 41.1 grams per tonne silver and 0.34 grams per tonne gold over 1.2 metres (Assessment Report 710).

In 1987, drilling on the A zone yielded intersections of 0.82 per cent copper over 30.0 metres, including 1.62 per cent copper over 12.0 metres, from hole E-71 and 0.30 per cent copper over 42.0 metres in hole E-72 (Assessment Report 16778).

Work History

During 1965 through 1967, BHP-Utah Mines completed programs of geological mapping, soil sampling and ground geophysical programs on the area as the Bay and Cove claims. Sixty-two diamond drill holes, totalling 4035 metres, were reportedly completed on the A zone during this time but no drill logs of these are known.

During the 1970s, 18 drillholes, totalling 5047 metres, were reportedly completed around Frances Lake and west of the Island Copper (MINFILE 092L 158) pit.

In 1986, Utah Mines completed a program of soil sampling and ground magnetic and electromagnetic surveys on the area as part of the Island Copper Mine property. The following year, BHP-Utah Mines completed 14 drillholes, totalling 2905.0 metres, on the M 34 claim. In 1988, BHP-Utah Mines completed a 390.0 line-kilometre airborne magnetic and electromagnetic survey on the area. In 1994, BHP Minerals Canada Ltd. completed 18 diamond drill holes, totalling 1783.1 metres, on the area.