The oldest rocks in the Ray showing area consist of a thick sequence of weakly metamorphosed siltstones and argillites which are considered to be part of the Devonian to Permian Stikine Assemblage. Overlying this sequence are black shales, siltstones, greywacke and conglomerates of the Upper Triassic Stuhini Group. Intruding the Mesozoic rocks are Jurassic to Tertiary plutonic rocks which range in composition from syenite to diorite. Contact metamorphism consists of large zones of hydrothermal alteration with the formation of some migmatites and cataclasites. Early Jurassic Texas Creek Plutonic Suite, syenite and orthoclase porphyry rocks intrude the stratigraphy and the Triassic-Jurassic Iskut River (Bronson) stock consisting of monzodiorite to gabbro is found to the southeast.
On the property the Upper Triassic sedimentary rocks are dominated by black to grey, foliated and well-bedded argillaceous siltstone. The siltstone grades into well-indurated, poorly foliated and well-bedded chert and some limestone. The volcanics consist mainly of mafic flows which include feldspar porphyry volcanic flows.
Sericite schist occurs in the eastern portion of the Hemlo West 16 claim. Metamorphosed sediments in this area, which consist of siltstone, sandstone and shale, are believed to be Lower Triassic in age. It is pale green in color, well-foliated, variably siliceous and hosts variable amounts of disseminated, veined and laminated pyrite. Structural relationships suggest that this rock unit is unconformable, however, some coarsely crystalline limestone with faults along both contacts, occurs within the schist.
Chloritization and some epidotization of the volcanics and sedi- ments appears to be related to regional metamorphism. Pervasive seri- citization which characterizes the schist is possibly related to the mineralization which accompanies the sericite schist. Outcrops of quartz sandstone adjacent to the sericite schist contain minor amounts of sericite suggesting that the sericitization is gradational between the two.
Widespread disseminated and veined pyrite is abundant on the Hemlo West 16 claim. Accompanying the pyrite are local concentrations of chalcopyrite and galena. This mineralization appears to be associated with the sericite schist, and in some cases the pyrite occurs as laminations parallel to the foliation. Also on the Hemlo West 16 claim veined pyrite mineralization appears to be confined to the chert in quartz-carbonate-dolomite gangue.
The Ray No. 1 showing occurs within a steep-sided gully within quartz-sericite schist with some garnet and chlorite. A fault, striking northwest and dipping 55 degrees southwest, between coarsely crystalline limestone and schist is mineralized with sphalerite and galena. In 1966, a 0.34 metre sample taken across sulphide minerali- zation with iron and manganese oxide stained fault rock and clay gouge assayed 1.37 grams per tonne gold, 44.57 grams per tonne silver, 0.14 per cent lead and 2.0 per cent zinc (Minister of Mines, Annual Report, 1966, page 35).
A pod of massive sphalerite, chalcopyrite, galena, pyrite and quartz is reported to occur along a foliation plane within the seri- cite schist. In 1966, a chip sample across 0.7 metres assayed 18.17 grams per tonne gold, 1769.0 grams per tonne silver, 2.68 per cent lead, 9.3 per cent zinc and 8.92 per cent copper (Minister of Mines, Annual Report, 1966, page 35).
In 1987, a rock sample taken from Trench A (Ray No. 1 showing), which hosts secondary mineralization consisting of pyrite and sphalerite with intensely weathered biotite, assayed 3.05 grams per tonne gold, greater than 200.0 grams per tonne silver, 0.95 per cent arsenic, 0.33 per cent copper, 0.33 per cent lead and 0.98 per cent zinc. Mineralization within Trench B consists of a 3 to 30 centimetre wide chalcopyrite-bornite vein with associated parallel pyrite veins. A sample from the chalcopyrite-bornite vein assayed 3.05 grams per tonne gold, 92.6 grams per tonne silver, 0.95 per cent lead with greater than 1.0 per cent copper and zinc (Dandy, 1988).
Regarding the re-opening and re-sampling of these trenches, the best result comes from Trench No. 1B, which returned values of 8.32 per cent copper, 3.90 per cent lead, 12.02 per cent zinc, 884.895 grams per tonne silver and 32.639 grams per tonne gold over 0.5 metres (Assessment Report 17122).
Earlier reports suggest the mineralization is the result of fault controlled, epithermal processes, however, it is now thought the genesis may be associated with some form of volcanogenic massive sulphide deposit.
The Ray was found by Iskut Silver Mines Limited who held 34 recorded claims as the Ray and Joann groups in 1965. Work on the property in 1965 and 1966 included geochemical soil sampling, ground magnetometer surveys, trenching and stripping, and 70 metres of packsack diamond drilling in 4 holes. The property was subsequently expanded to 68 claims in the Ray, Joann, and Grace groups. During 1970 Cerro Mining Company of Canada Limited carried out geolocial and geochemical surveys, and Iskut Silver carried out a detailed magnetometer survey on Joann 1 and Grace 6 claims. Amax Exploration, Inc., carried out geological mapping, and geochemical soil, silt, and water surveys in 1971.
The Ray occurrence occurs to the immediate west of the area later worked as the Meridor and Snip North properties. The Ray area is part of that area later worked by the Iskut Joint Venture (Hemlo West property). Refer to Gregor (104B 357) and Snip North (104 312) for further geological information and details of a common work history.
