The AU occurrence is located approximately 250 metres south of Waterloo Creek and approximately 3 kilometres northwest of Lightning Peak.
The Lightning Peak area is underlain by limestone and greenstone of the Devonian-Triassic Harper Ranch Group. These are underlain and intruded by granodiorite and diorite of an unnamed Middle Jurassic intrusion. Quartz porphyry dikes are common in the Harper Ranch Group; pegmatitic variations are sometimes associated with mineralization in the Lightning Peak camp. Several remnants of Miocene-Pliocene Chilcotin Group plateau basalts are found in the area, including the summit of Lightning Peak.
The occurrence consists of several north-trending quartz veins, varying from 5 to 60 centimetres wide, that contain pyrite and minor amounts of galena and sphalerite. Argentite has been noted in a polished section. Films of native copper have been observed on quartz fracture surfaces. The veins contain vugs, and sooty decomposition products (wad?) are common.
A 1930 report describes approximately six veins, all of which strike approximately north-south and dip at high angles to the east or west. A shaft exposes a 25-centimetre wide vein with a 10-centimetre thick lens of massive pyrite, galena, sphalerite and chalcopyrite. Elsewhere, the vein contains streaks and bunches of pyrite. The vein has been traced for approximately 120 metres. It is terminated by an east-west–trending shear zone approximately 25 metres north of the shaft. A grab sample assayed 4.1 grams per tonne gold, 838 grams per tonne silver, 13 per cent lead and 4.5 per cent zinc (Geological Survey of Canada Summary Report 1930A, page 80A).
Approximately 50 metres southwest of the shaft, a 90-centimetre wide, rusty-weathering shear zone contains quartz veining and pyrite. Another vein, lying 10 metres west of the shaft vein, occurs on the footwall of a quartz porphyry dike that dips steeply to the west. This vein is approximately 15 centimetres wide and is sparsely mineralized with pyrite and galena, as are most of the other veins on the property.
The Lightning Peak area has seen extensive exploration since the early 1900s, with most of the exploration effort directed at the numerous polymetallic, shear–zone–hosted quartz veins in this camp. The AU showing is near the Waterloo mine (MINFILE 082ENE017), 550 metres to the southwest, and has been included in many of the programs covering the Waterloo property. In 1931, the AU shaft, which was started in 1930, was deepened to 21 metres with a 22-metre crosscut and a 12-metre drift. The vein, exposed in the drift, varies in width up to 60 centimetres, but averages 20 centimetres. A quartz porphyry dike is in close proximity to the vein. In 1931, 17.69 tonnes of gold ore was shipped from the AU property (Minister of Mines Annual Report 1931, page A122). This shipment was recorded as production from the Waterloo mine.
Later reports describe a total of 45.4 tonnes of ore being shipped, averaging 36.9 grams per tonne gold, 670.3 grams per tonne silver, 6.7 per cent lead and 4.7 per cent zinc (Property File - J.C. Stephen [1967-10-20]: Report - Lightning Peak Area - Mastodon Highland Bell Mines Ltd.).
In 1966, Bralorne Pioneer Mines Limited carried out a geochemical survey of the Waterloo mine and surrounding area. They were able to trace some quartz veins through areas of overburden on the mine property. In 1967, Mastodon-Highland Bell Mines prospected and sampled the area. Two dump grab samples averaged 6.5 grams per tonne gold, 164.2 grams per tonne silver, 0.88 per cent lead and 0.48 per cent zinc (Property File - J.C. Stephen [1967-10-20]: Report - Lightning Peak Area - Mastodon Highland Bell Mines Ltd.).
In 1968 and 1969, International Mine Services Ltd. carried out geochemical and geological surveys and a diamond drill program on the adjacent Waterloo mine property. In 1974, K.L. Daughtry carried out a magnetometer survey over the Rhondda claim, which covered the AU and Silver Spot Loc. 9 (MINIFLE 082ENE026) showings. The survey identified lithological contacts but provided little information about shear zones. In 1978, W.G. Botel carried out a 16.9-kilometre VLF-EM survey over the area.
In 1983, Cous Creek Copper Mines examined and sampled the area. Samples from a shaft assayed up to 68.4 grams per tonne gold, 837.9 grams per tonne silver, 10.5 per cent lead and 8 per cent zinc, whereas samples of a second, north-striking, quartz-pyrite vein yielded 4.1 grams per tonne gold and 17 250.5 grams per tonne silver (Property File - Cous Creek Copper Mines Ltd. [1983-12-09]: News - Cous Creek Copper Mines Ltd. - Waterloo Mine).
In 1992, Zalmac Mines completed a program of geological mapping, soil and rock sampling, surveying and aerial photograph studies on the area as the P and Z claims.
In 2011, Tower Resources optioned the property and completed a program of geological mapping and sampling from outcrops, trenches and dump piles located near old workings. New areas of precious-metal–enriched rocks were also identified during this work. The 39 samples, collected over an area of 4 by 1.3 kilometres, average 112 grams per tonne silver and 0.9 gram per tonne gold. Highlights from this sampling program include two samples from mineralized vein material that returned up to 141.0 grams per tonne silver, 25.40 grams per tonne gold and 1.8 per cent lead (http://www.towerresourcesltd.com).
In early 2012, Tower Resources conducted a predrilling exploration program consisting of geological mapping, prospecting, ground magnetic and VLF electromagnetic surveys and confirmation soil geochemistry. Highlights of this sampling program include a grab sample from the AU mine that yielded 794 grams per tonne silver, 45.7 grams per tonne gold, 7.82 per cent lead and 3.63 per cent zinc (Press Release, Tower Resources, November 21, 2012). Later in 2012, Tower Resources completed 11 drillholes, totalling 1200 metres.
