The Red Reef showing is located on the northwest slope of Mount Rainey, 2 kilometres southeast of Stewart. Various showings have been investigated in this area since 1910.

The occurrence is hosted in argillite and tuff with minor intercalated recrystallized limestone of the Lower Jurassic Unuk River Formation (Hazelton Group) adjacent to Eocene granodiorite of the Hyder pluton (Coast Plutonic Complex). The bedded units strike 116 to 130 degrees, dip 70 to 78 degrees southwest and are locally folded and cut by granitic pegmatite and lamprophyre dikes.

The showing consists of siliceous skarn zones up to 3 metres wide, developed parallel to the bedding of the enclosing rocks. The zones contain massive patches, blebs, disseminations and stringers of pyrrhotite, pyrite, minor chalcopyrite and bornite in a gangue of quartz, garnet, epidote, diopside and biotite. These zones are often cut by northwest and northeast striking lenses, veins and stringers of quartz and massive pyrrhotite, pyrite, galena and sphalerite with disseminated chalcopyrite.

Chip sampling in an adit resulted in copper assays of between 0.62 and 3 per cent (Property File - Ramani, 1974, page 5). Chip sampling along a skarn zone over a length of 15 metres and a width of 2.4 metres assayed trace gold and silver (Property File - Mandy, 1937, page 6).

Work History

In 1910, work comprised 6 metres of tunnel and various opencuts. In 1913, the main tunnel was continued a distance of 23 metres and a body of quartz, carrying low copper and gold values, was intersected. This quartz was crosscut for a distance of 6 metres before running into the country rock, giving a total width of quartz of 7.6 metres. The crosscut was then continued another 7.9 metres, but without encountering any orebodies other than one or two small stringers. On one of the outcrops above this tunnel, 6 metres was driven in on a quartz vein about 1.2 metres in width, also carrying low gold and copper values. In 1938, some additional drifting was done by contract during the summer.

In 1981, Domody Resources Ltd. prospected the area Contact, Red Reef and Sky claims. During 1984 through 1987, Teuton Resources Corp. completed programs of prospecting, geochemical (rock, soil and stream sediment) sampling and a 24 line-kilometre airborne geophysical survey on the area.

In 1990, Amphora Resources completed an 8.1 line-kilometre airborne magnetic and electromagnetic (VLF) survey on the area.

In 2018, Granby Gold Inc. completed an 88.25 line-kilometre airborne magnetic and gamma-ray spectrometry survey on the area.