Property-scale mapping shows that mineralization at the GFJ showing is largely hosted by andesite block breccias and tuffs of the Salmon River Formation, Hazelton Group. The hosting unit is in thrust contact with overlying undifferentiated andesite and epiclastic rocks. A stock of Eocene quartz monzonite occurs about 2.5 kilometres south and contact with marine sedimentary and volcanic rock of the Upper Triassic Stuhini Group occurs about one kilometre northeast. In general, mineralization trends west-southwest from the thrust contact for about 1.5 kilometres.
The GFJ showing is a lode gold vein occurrence up to 750 metres in length and from 0.5 to 1 metre in width. Mineralization was found within a shallowly-dipping shear-controlled pyritic quartz vein, consisting of banded quartz, chlorite, pyrite, arsenopyrite and possibly tetrahedrite. Wall rocks were described as andesite tuff. Native gold is reported.
Several separate veins or zones of veins were mapped. One zone consists of a series of 20 to 40 centimetre flat-lying veins and 2 to 4 metres wide silicified zones of sub-horizontal vein stockworks. This zone is exposed over a length of 195 metres. Sulphides and alteration in this zone are weak. Another vein extends 110 metres with widths ranging from 15 to 80 centimetres, dipping about 30 degrees to the east. This vein consists of banded quartz, siderite and sulphides, and contains up to 33.7 grams per tonne gold (as reported in Assessment Report 27511). Weak silicification extends up to 5 metre in the hanging wall while the footwall is moderately silicified for 1 metre. Another poorly exposed vein is sub-horizontal, 12 to possibly 50 centimetres thick, and extends for about 90 metres. This vein consists of quartz, pyrite, arsenopyrite and chalcopyrite. Gold assays from this vein range up to 46.4 grams per tonne (as reported in Assessment Report 27511). Several other veins were described but do not carry significant gold.
At one point, three isolated exposures were sampled, yielding assays up to 72.7 grams per tonne gold and 562 grams per tonne silver (http://www.kenrichmining.com, June 1998).
During 1987, Bighorn Development Corporation conducted an exploration program consisting of rock geochemistry, prospecting, trenching and silt sampling on the Corey claims and the documenting report showed assays and maps of the GFJ grid (Assessment Report 17404). According to Assessment Report 27511, the first recorded work on the GFJ showing was in 1993 when Assessment Report 23805 described the results of a reconnaissance sampling program. More extensive work was carried out in 1993 when a grid was established, and the showing was mapped and sampled (Assessment Report 24373). Assessment Report 24373 noted that Placer Dome previously discovered that high-grade float in the area, presumably in 1992. No work has been carried out on the GFJ showing from 1996 to 2003.
In 2016, C.J. Greig & Associates Ltd., on behalf of Eskay Mining Corp., conducted reconnaissance soil and stream sediment sampling in an area that has been mapped as Stuhini Group rocks, east of Ted Morris glacier on the southern part of the SIB property. Samplers collected 65 soil samples along a northwest-trending ridge located on the east side of the Ted Morris glacier. The soil line traversed an area mapped as Stuhini Group sedimentary and volcanic rocks. Samples were collected at 75 metres intervals along the line for a total line-length of about 4800 metre. Three stream sediment samples were also collected about 1 kilometre south of the soil line. A total of 126 rock samples were collected in a region encompassing about 35 square kilometres that surrounds the Ted Morris glacier. Areas sampled include Red Lightning (104B 605) and GFJ (104B 233) and areas farther south toward Ted Morris Glacier showing (104B 236).
Several rock samples were collected near the GFJ prospect in 2016. Of note was sample CB-16-044 taken just north of the prospect which graded 91.7 grams per tonne silver, 0.25 gram per tonne gold, 0.25 per cent copper, 0.85 per cent lead, 0.48 per cent zinc and 0.196 per cent antimony (Assessment Report 36739). The sample was from a quartz-sulphide vein contain sphalerite, galena, chalcopyrite and chalcocite. The vein was reported as subcrop in carbonate altered rock. The sample was located 414105 East and 6257540 North.
See Sib (Lulu) (104B 376) and Cumberland (104B 011) for further details of work done on the Sib and Corey property.
