The Steelhead showing is about 16 kilometres from tidewater on Douglas Channel, on a ridge top between Ecstall Lake and Quaal River, 58.5 kilometres southwest of Kitimat and 87 kilometres southeast of Prince Rupert.
The Steelhead showing is in the Ecstall Greenstone Belt, underlain by intercalated felsic and intermediate volcanics and fine clastic sediments. The Ecstall belt is a north-northwest trending, high-grade metamorphic belt bounded by the elongate mid-Cretaceous Ecstall pluton on the west and the Paleocene Quottoon pluton on the east. The rocks include sericite schist, quartz sericite schist, pyritic quartz sericite schist, chlorite schist, andesite, tuff, greywacke, siltstone, and argillite.
Pyrite, sphalerite, and chalcopyrite occur in the pyritic quartz sericite schist. Sampling of a pyritic horizon gave assays up to 0.3 per cent copper, 3.8 per cent zinc, and 5.8 grams per tonne silver (Assessment Report 15491).
In 1995, Atna Resources Ltd., under joint venture with Ecstall Mining Corporation, conducted an electromagnetic survey and diamond drilling (1075 metres in 8 holes) on the Horsefly (103H 014) and Steelhead showings.
See also Packsack (103H 013).
Located 1 kilometre south of the Horsefly (103H 014) prospect, the Steelhead showing was discovered in 1986 during follow-up of Noranda Exploration’s airborne EM survey. Investigation of the area around a series of strong ABEM anomalies outlined 3 pyritic quartz-sericite schist units hosting from 1 per cent to 30 per cent pyrite. In detail, these units consist of pyritic rhyolite, quartz-sericite schist and breccias (Schmidt, 1996a, p.8). Mineralization occurs as pods or patches of pyrite and pyrrhotite, with associated chalcopyrite and sphalerite. Some mineralization occurs in fragments within the breccias. As at the Horsefly prospect, the black siliceous argillite horizons in the Steelhead area are also mineralized with disseminated pyrite, pyrrhotite and rare chalcopyrite. Local geology consists of a succession of mafic to intermediate to felsic volcaniclastic rocks and flows, and minor intercalated sedimentary units (Schmidt, 1996a, p.6-7). Schmidt also reports (op. cit.) that fragmental rocks on the east side of the Steelhead grid have well-preserved primary textures - abundant lapilli and crystal fragments and rare bomb sags are evident. Numerous exposures of graded beds were also noted but textures were not clear enough to ascertain tops.
The best assays obtained from a series of grab samples were 1.65 per cent copper, 3.8 per cent zinc, 5.8 grams per tonne silver and 120 parts per billion gold (Schmidt, 1996a). Three holes, totaling 424 metres, were drilled at Steelhead by Atna Resources Ltd. in September, 1995; the best intersection assayed 0.027 per cent copper, 1,276 parts per million lead, 362 parts per million zinc, 13.8 parts per million silver and 24 parts per billion gold over 4.9 metres in an argillite unit hosting disseminated pyrrhotite and trace chalcopyrite (Schmidt, 1996a).
The Steelhead showing was part of the 2019 airborne VTEM survey conducted for Kingfisher Resources Ltd. The airborne survey was aimed at detection of structures and/or conductors related to potential Cu-Au-Zn-Ag VMS-style mineralization (Assessment Report 39155).
