The Tan showing area is underlain mainly by marine sedimentary and volcanic rocks of the Upper Triassic Stuhini Group, consisting of volcaniclastics, tuffs, tuffaceous breccias, argillites and minor limestone. These are intruded by several small structurally controlled stocks of hornblende diorite to augite porphyry of Triassic or possibly Jurassic age. The rocks are regionally metamorphosed to lower greenschist facies. Faults, with shear directions of 018 to 027 degrees, occur in the area. Mississippian rocks of the Stikine Assemblage are mapped just north of the Tan (104K 103) area and south of Bearskin Lake.

Quartz-iron carbonate gossan zones, adjacent to a northwest trending fault, contain ankerite, hematite, pyrite and sometimes chalcopyrite, bornite and malachite as blebs, fracture fillings and disseminations. A 3-metre chip sample assayed 10 per cent copper and 0.9 gram per tonne gold (Assessment Report 15894). A previous sample, 500 metres to the east, assayed 9.8 grams per tonne silver and 3.0 grams per tonne gold (Assessment Report 13840).

WORK HISTORY

In July 1983, the TAN group was staked by Chevron Canada Resources and consisted of the Tan 3 to 6 and SUN 1 claims. This group surrounds the borders of ORO 1 and ORO 5-10 claims which were staked in 1983 prior to the TAN group. Chevron Canada Resources conducted geological mapping and a rock and soil sampling program on their TAN Group, possibly including additional work in 1984 or 1985 (Assessment Reports 11820 and 13840). In 1983, a total of 360 soil samples were collected from the SUN 1 and TAN 5 claims by Chevron Resource in the vicinity of the Oro and Tan showings. The Muse showing (104K 119) is located just north of the Sun 1 claim. The majority of samples had background values of gold (5 parts per billion), silver (0.1 part per million), arsenic (15 parts per million), and antimony (1 part per million). The best area was on TAN 5 where there are 4 samples which had gold values of 220 parts per billion, 170 parts per billion, 160 parts per billion and 160 parts per billion. Follow up found no reasons for the high gold values. A VLF-EM I6 geophysical survey was also completed. Strong conductors in two main areas were found and seemed to correlate with air-photograph lineaments.

From 1983 to 1986, Sage Resources conducted mapping and sampling, collecting some forty-eight rock chip samples over the ORO claims and around Chevron's Tan (104K 103) showing area (Assessment Report 15894).

In 1992, a BC Geological Survey geological mapping project in the Tatsamenie and Bearskin lakes area resulted in an updated regional geological framework and the discovery of several new showing including Muse showing (104K 119) just south of the Tan.

In 2019, Brixton Metals Corporation expanded their Thorn property through staking and acquisition of claims including those covering all the Tan showings as well as the Oro and Muse showings. In 2020, Brixton Metals Corporation completed a program of geochemical (rock and soil) sampling, a 12.5 line-kilometre ground induced polarization survey, a 715 line-kilometre airborne magnetic and electromagnetic survey and 19 diamond drill holes, totalling 5292 metres, on the area of as part of the Thorn property. Drilling was performed on the Outlaw (MINFILE 104K 176) occurrence area. No work is reported on the Tan and Oro showings since their discovery in the earliest 1980s or the Muse showing since discovery in 1992.

For related geological and work history information refer to the nearby Tan showings (104K 101, 102 and 103), ORO (104K 039), Muse (104K 119), and to Golden Bear mine (104K 079) located about 5 kilometres north.

Refer to Thorn (104K 031), Chivas (104K 180), East Outlaw (104K 083), Oban (104K 168), Trapper (Inlaw) (104K 078) and Metla (104K 161) for details of the work history of the greater Thorn property.