The Copper Group Crown-granted claims are located on the northeast side of Treat Creek on the southern slopes of Treasure Mountain. This is on the east side of Jervis Inlet, at Prince of Wales Reach.

Regionally, the area is underlain by a series of northwest-trending volcanic and marine sedimentary rocks of the Lower Cretaceous Gambier Group and argillite, greywacke, wacke and conglomerate turbidites of the Lower to Middle Jurassic Bowen Island Group, which form a roof pendant that has been intruded by diorite and quartz diorite of the Jurassic to Cretaceous Coast Plutonic Complex.

Locally, the host strata comprise a series of fine-grained andesitic volcanic tuffs and agglomerates with included layers of argillite, chert, limestone, and basalt flows. The whole package has been extensively altered by a quartz diorite phase of the Coast Plutonic Complex.

Skarn mineralization occurs along a parallel series of east-trending structures. Garnet and epidote are the major skarn minerals. Contained within the skarn are lenticular, massive bodies of magnetite and pyrrhotite with minor chalcopyrite, pyrite and sphalerite. Pyrite, magnetite, pyrrhotite, chalcopyrite, sphalerite and galena are also sporadically disseminated in the skarn zones and silicified volcanics. Disseminations of chalcopyrite and molybdenite occur in quartz veins and stockworks in the vicinity of the skarn zones.

In 1917, a sample taken across 1.2 metres from the face of the no. 1 level adit assayed trace gold, 27.4 grams per tonne silver, 1.0 per cent copper and 19.3 per cent iron, and dump samples from the no. 2 and 3 level adits yielded 0.7 gram per tonne and trace gold, 41.0 and 20.5 grams per tonne silver, 1.1 and 1.3 per cent copper with 33.9 and 23.4 per cent iron, respectively (Minister of Mines Annual Report 1917, page 283).

In 1971, a drillhole (T-4) located at approximately 700 metres elevation and approximately 450 metres north-northwest of the plotted location of the adits is reported to have yielded 0.15 per cent copper over 61.9 metres, including 0.23 per cent copper over 12.2 metres (Property File - Unknown (1975-01-01): Report on Map Location No. 9 - T).

In 1987, a chip sample (JER87-4) over 1.0 metre of disseminated pyrite, chalcopyrite and galena in a greenstone, exposed at an elevation of approximately 615 metres and in the presumed area of the adits, assayed 0.81 gram per tonne gold, 100.3 grams per tonne silver, 0.24 per cent lead and 0.06 per cent bismuth; the following year, a nearby chip sample (JRF88-R9) yielded 0.15 per cent lead, 0.11 per cent zinc and 20.6 grams per tonne silver over 0.6 metre (Assessment Report 18346).

In 1993, a chip sample (R43) from a zone of silicified and pyritic andesite exposed along a road near the historical drillhole T-4 yielded 1.96 per cent zinc over 0.08 metre (Assessment Report 23238).

Work History

The Copper Group of claims, which included the Eldorado, Colorado, Portland, Columbia, Beaver, Coon and Otter claims, were originally staked in the late 1890s.

During the period of 1917 to 1922, a large amount of work was done to develop the occurrences with a series of six adits on four levels and over a vertical elevation of approximately 66.5 metres being driven to explore the mineralization. By 1922, the no. 1 level adit had been driven for approximately 9.1 metres, mostly in gravel and at an elevation of approximately 610 metres, and two short adits had been driven for approximately 5.5 and 2.4 metres on the no. 2 level, located approximately 21 metres below the no. 1 level. The no. 3 level adit, located a further 15 metres downslope, had been driven for approximately 20.5 metres with a 3-metre crosscut, while a second no. 3 level adit, located approximately 15 metres to the west of the first adit, was driven for approximately 18.3 metres with a 6.1 metre drift. The no. 4 level adit is located approximately 30.5 metres below the no. 3 level adits and was driven for approximately 15.2 metres with a 3-metre drift. Other mineral showings are reported to have been located between 152 and 762 metres elevation, with another adit being driven at an elevation of approximately 305 metres and trenches at elevations of approximately 157, 244 and 427 metres. The exact locations of the adits and related workings are unknown.

In 1959, Phelps Dodge is reported to have completed a dip-needle survey on the area. In 1965 and 1966, when Gunnex Ltd. conducted a mapping and sampling program of the historical Copper Group occurrences. In 1968 or 1969, Jervis Inlet Mines Limited completed approximately 610 metres of diamond drilling in four holes on the historical Copper Group occurrences.

During 1971 through 1973, El Paso Mining conducted programs of geological mapping, geochemical (rock and soil) sampling, ground magnetometer and VLF-EM surveys and four diamond drill holes, totalling approximately 762 metres, on the area as the T claims.

In 1987 and 1988, Ashworth Explorations Ltd. conducted a program of geological mapping and rock sampling on the area as the Chris, Goliath, Maria, Nita and Orca claims of the Jervis Inlet property.

In 1993, Arrowhead Exploration Services, on the behalf of Anthian Resources Corp., conducted a program of geological mapping, geochemical (rock and soil) sampling and a 10.3 line-kilometre ground magnetic and electromagnetic (VLF) survey on the area as the Treat property.

In 2020, Saxifrage Geological Services Ltd. conducted a minor rock sampling and prospecting survey on the area as the Jervis Inlet Cu-Zn property.