The main Astonisher gold occurrence is located on a ridge saddle in the northeastern headwaters of Stirrup Creek, approximately 3.5 kilometres south-southwest of Moore Lake. The former Astonisher adit is located approximately 1.2 kilometres to the southeast, near the southwestern corner of the Astonisher (L.7979) Crown grant, at an elevation of approximately 1840 metres. The prospect is situated approximately 13 kilometres west of the Fraser River and 45 kilometres west of Clinton, B.C.
The area is underlain by marine sedimentary rocks of the Lower Cretaceous Jackass Mountain Group, which have been intruded by sills and dikes of Tertiary to Cretaceous feldspar porphyry and quartz porphyry. The Jackass Mountain Group consists of conglomerate, siltstone and sandstone, generally trending to the north or northeast and dipping to the west.
Locally, gold-bearing, vuggy, limonitic chalcedonic quartz veins and narrow limonitic fracture zones cut the sedimentary and intrusive rocks; in places these veins appear to be stratiform. The veins and fracture zones contain native gold, stibnite, arsenopyrite, minor pyrite and anomalous mercury. A positive correlation exists between arsenic and gold in these veins. Locally, the sandstone contains disseminated pyrite, while the intrusives contain disseminated galena, sphalerite and stibnite.
In 1973, trench sampling yielded values of up to 1.4 grams per tonne gold over 15 metres; including 3.4 grams per tonne over 3 metres (Assessment Report 4743).
In 1987, samples (62042, 62118, 62133) of narrow hematized veins or faults from former trenches, trending north to north west, yielded values of 12.8 grams per tonne gold with 5.4 grams per tonne silver, 36.6 grams per tonne gold with 8.0 grams per tonne silver and 187.1 grams per tonne gold with 17.6 grams per tonne silver, respectively, while a trench channel sample yielded 3.5 grams per tonne gold over 1.0 metre (Assessment Report 17336). During the same year, diamond drilling (hole 87-3) intercepted a narrow quartz-pyrite-arsenopyrite mineralized zone hosted by sandstone that assayed 20.9 grams per tonne gold over 0.18 metre (Assessment Report 17336).
In 1988, diamond drilling (hole 88-5) intercepted 1.10 metres assaying 14.99 grams per tonne gold (Sample 248161; Assessment Report 18352).
In 1996, a grab sample (MM96-80) across a 10 metre road cut or trench yielded 0.41 grams per tonne gold (Assessment Report 25042).
In 2005, diamond drilling yielded up to 0.31 gram per tonne gold over 7 metres, including 17.19 grams per tonne gold over 0.8 metre from a mineralized zone striking 85 degrees with a near vertical dip (DDH SC-05-02; Assessment Report 28032).
In 2015, sampling of drill cores, from 2007, assayed up to 4.87 grams per tonne gold over 1.5 metres (DDH S07-04; Assessment Report 35804).
The Astonisher claims were originally staked in the mid-1920’s; historical workings are reported to consist of a half-dozen short adits and a winze, which were constructed on the Crown grants by 1933. In 1969, Rio Tinto prospected the area. In 1973, Canex Placer completed a program of rock and soil sampling, trenching and geological mapping on the area as the Watson Bar Creek group of claims. In 1987 and 1988, Chevron Minerals completed programs of geological mapping, trenching, a 29.7 line-kilometre VLF-EM survey and 6 diamond drill holes, totaling 916.7 metres, on the area as the W 1-12 claims. In 1996, Navarre Resources completed a program of rock, silt and soil sampling on the area as the SC claim group. In 2005, Anglo-Canadian Uranium Corp. completed three diamond drill holes, totaling 649.8 metres. In 2012, Anglo-Canadian Mining completed a program of airborne magnetic and radiometric surveys on the area. In 2015, drill cores, from 2007, were re-sampled for J.M. Stewart (Assessment Report 35804).
