The BGS-Galena Ridge (Pyramid) occurrence is located at an elevation of approximately 1500 metres on a northeast-facing slope, west of the South Unuk River and approximately 11 kilometres northwest of Mount Pearson.
The area is underlain by the Upper Triassic Stuhini Group, which consists of Upper and Lower divisions. The Lower division is dominantly sedimentary with undifferentiated, fine-grained, well-bedded rocks and coarser conglomerate layers, whereas the Upper division is dominantly volcanic and volcaniclastic with mafic to intermediate tuff and volcanic breccia, mafic porphyritic flows, felsic flows and flow breccia. The Stuhini Group is crosscut by a granitoid batholith and stocks of the Eocene Coast Plutonic Complex that display a range of rock types including medium- to coarse-grained biotite±hornblende granite and granodiorite with minor quartz diorite.
The BGS and Galena Ridge zones occur over a 1.2-kilometre-long, northwest-trending shear zone with associated gold-bearing quartz veins identified intermittently along the structure. The northwestern part of the trend hosts the Galena Ridge zone, which encompasses quartz veins and associated galena stringers and brecciated margins. In the southwest (BGS zone), the veins are predominantly bull quartz, hosting clotty pyrite and chalcopyrite. The Galena Ridge zone is centred approximately 700 metres northwest of the BGS zone.
Another zone of mineralization, referred to as the Q19 zone, is located approximately 450 metres northeast of the BGS zone and comprises at least three quartz veins, up to 3.60 metres wide, exposed over a strike length of approximately 25 metres along a trend of 110 degrees and dipping 65 degrees north. Shear margins of the vein are reported to contain massive galena with associated ‘high-grade’ gold values.
Refer to the Doc (MINFILE 104B 014) prospect for related details and a common property work history.
In 1987, trenching on the Q19 vein by Magna Ventures is reported to have yielded up to 64.40 grams per tonne gold and 765.1 grams per tonne silver over 1.10 metres with an average of 7.65 grams per tonne gold and 72.1 grams per tonne silver over 5.78 metres, whereas a ‘high-grade’ grab sample assayed up to 210.00 grams per tonne gold and 587.8 grams per tonne silver (Mitchell, A.J., Prowse, N.D. [2020-06-08]: NI 43-101 Technical Report on the Doc Property).
In 1999, Hunter Exploration conducted a prospecting program on the Doc property, which was encompassed by the Eldorado 2 and 4 claims. This resulted in the discovery in subcrop of the BGS showing, which assayed up to 44.66 grams per tonne gold and 219 grams per tonne silver (Assessment Report 26256). The showing consisted of quartz vein rubble in ‘subcrop’ exposed over an area of approximately 25 by 6 metres near the base of a snowfield. The vein material consists primarily of white quartz with abundant pyrite and chalcopyrite, closely resembling the Q17/Q22 veins of the Doc (MINFILE 104B 014) prospect to the north. Sampling of the Galena Ridge zone is reported to have yielded up to 13.25 grams per tonne gold and 138.5 grams per tonne silver.
In 2013, prospecting located a new vein set at the BGS showing or just south, just a few hundred metres northeast of the Quinn-Eskay (MINFILE 104B 471) occurrence discovered by Cache Exploration in 2011. This new vein set shows potential high-grade mineralization beacuse it hosts pyrite, specularite, and chalcopyrite. The veins are not as thick as the main set but do show potential for extension along strike. Some veins show mineralization, weak shearing and alteration at the margins, but one vein showing massive sulphides potentially has more significant mineralization. These veins are hosted in metavolcanics as well.
In 2018, a rock sample from a 2-centimetre-wide quartz vein hosting pyrite, chalcopyrite, magnetite and malachite, taken a short distance west of the BGS zone, assayed 0.62 gram per tonne gold, 454.0 grams per tonne silver and 4.86 per cent copper (Mitchell, A.J., Prowse, N.D. [2020-06-08]: NI 43-101 Technical Report on the Doc Property).
In 2019, a 0.35-metre chip sample from the Galena Ridge zone yielded 12.80 grams per tonne gold and 263.0 grams per tonne silver, whereas a channel sample from the same zone yielded 7.75 grams per tonne gold and 286.0 grams per tonne silver over 0.44 metre (Mitchell, A.J., Prowse, N.D. [2020-06-08]: NI 43-101 Technical Report on the Doc Property). Also at this time, three rock samples from the BGS zone yielded an average of 3.68 grams per tonne gold (up to 4.04 grams per tonne) and 74.2 grams per tonne silver (up to 170.0 grams per tonne), whereas channel sampling of the Q19 zone yielded up to 71.1 grams per tonne gold, 721 grams per tonne silver, 0.11 per cent copper and 12.7 per cent lead over 0.70 metre (Mitchell, A.J., Prowse, N.D. [2020-06-08]: NI 43-101 Technical Report on the Doc Property).