The Hedley North prospect outcrops in the headwaters of Redtop Gulch, 2 kilometres northeast of Highway 3 and 3 to 3.5 kilometres east-southeast of Hedley.
The area north of Redtop Gulch is underlain mostly by siltstone, argillite, limestone and lesser chert and conglomerate of the Upper Triassic Hedley Formation (Nicola Group). The sediments are flanked to the southeast, in the immediate vicinity of the creek, by granodiorite of the Middle Jurassic Cahill Creek pluton. Early Jurassic Hedley Intrusions, occurring as hornblende porphyry sills, intrude the sediments.
An adit, 17 metres long, explores an outcrop of rusty-weathering breccia comprised of Hedley Formation plagioclase porphyritic andesite and lesser argillite fragments. The breccia contains a thin horizon of argillite-limestone-chert interbeds, which strikes north and dips moderately west. The breccia is mineralized with disseminated to fracture-controlled pyrrhotite. Four chip samples taken across the 2 metre width of the adit assayed 0.004 to 16.85 grams per tonne gold (Assessment Report 14879, page 14, samples HR 69 to 73). Sample HR 70 assayed 16.85 grams per tonne gold, 2.5 grams per tonne silver, 0.011 per cent zinc and 0.005 per cent copper (Assessment Report 14879, assay certificate). A possible continuation of this zone of mineralization occurs 350 metres to the south, where limestone is intruded by a plagioclase porphyritic andesite dyke or sill. A sample of the andesite, with trace to 1 per cent pyrrhotite, assayed 7.78 grams per tonne gold and 4.6 grams per tonne silver (Assessment Report 14879, assay certificate, sample HR 76).
Trenching north, east and southeast of the adit encountered Hedley Formation siltstone, argillite, chert and minor thin limestone beds. Bedding strikes northeast with varying dips ranging from 20 to 50 degrees northwest. Hornblende porphyry sills crosscut the stratigraphy and are exposed in most of the trenches. The sediments exhibit weak skarn alteration in the form of calcsilicate skarn and skarned chert, and contain pyrrhotite, pyrite, chalcopyrite, arsenopyrite and galena, with low gold values.
Low precious metal values with elevated base metal values were encountered in the Corrall zone, 300 metres east of the adit. A sample from the North Corrall trench, consisting of garnetite skarn, with garnets up to 4 millimetres across and hosting disseminations and blebs of pyrrhotite, chalcopyrite and galena in a calcite gangue, assayed trace gold, 1.9 grams per tonne silver, 0.093 per cent copper and 0.107 per cent zinc (Assessment Report 16400, Figure 8, sample 463). A sample taken across a 0.60-metre wide carbonate-clay-epidote alteration zone in the adjacent South Corrall trench assayed 0.12 gram per tonne gold, 5.2 grams per tonne silver, 0.186 per cent copper and 36.17 per cent iron (Assessment Report 16400, Figure 9, sample 473).
An area of skarn alteration occurs in the Cahill zone, 500 metres southeast of the adit. A sample taken across 5 metres of light grey, fine-grained chert, with 1 to 5 per cent disseminated and patchy blebs of pyrrhotite, chalcopyrite and pyrite, assayed less than 0.005 gram per tonne gold, 1.1 grams per tonne silver and 0.008 per cent copper (Assessment Report 16400, Figure 10, sample 491).
The prospect was initially explored by Zurich Energy Corporation in 1982. Avenue Resources completed an extensive program of geological, geochemical and geophysical surveys and 244 metres of trenching in 1987.
