The Orn occurrence is located on the northern slopes of Mount Hall, approximately 2.8 kilometres south- south east of Holland Lake.

The area is underlain by gabbro sills (informally called the Mount Hall Gabbro) that are coeval with the Upper Triassic Karmutsen Formation, Vancouver Group. A west trending horizon of sediments, about 125 metres thick, occurs along the northern flanks of Mount Hall and Coronation Mountain and is encompassed by the gabbro. These sediments, belonging to the Mississippian to Pennsylvanian Fourth Lake Formation (Buttle Lake Group), comprise siltstone, cherty siltstone and minor sandstone.

Gabbro to the north of the sediment horizon is divisible into medium-grained and coarse-grained horizons. The coarse-grained variety is about 30 metres thick with hornblende crystals up to 1 centimetre in length. This rock contains up to 15 per cent medium- grained magnetite, 5 per cent disseminated and fracture filled pyrite and traces of chalcopyrite. The medium-grained magnetite is equi- granular, massive and contains up to 5 per cent magnetite. Two samples of the gabbro assayed 0.18 and 0.15 grams per tonne palladium (Assessment Report 17351). In 2002, samples of thin pyrrhotite veins and disseminated sulphides in a magnetite layer of the gabbro assayed up to 337 parts per billion gold, 68 parts per billion palladium, 10.5 parts per million silver, 2626 parts per million copper, 0.5 per cent titanium and 458 parts per million vanadium (Assessment Report 26632).

The gabbro is cut by abundant east-northeast to east-south- east trending, vertical to north dipping shears and quartz veins, up to 20 centimetres wide. Many of these structures are mineralized with pyrite and rarely chalcopyrite and contain anomalous levels of gold (up to 0.13 grams per tonne), silver (up to 6 grams per tonne) and copper (up to 1.03 per cent), (Assessment Report 17351, page 27). In 1990, a sample (LL-34) from a 20 centimetre wide quartz rich oxide zone assayed 240 parts per billion gold and 1200 parts per million copper (Assessment Report 20387). In 2002, sampling of quartz veins yielded values up to 373 parts per billion gold, 16 parts per billion palladium, 6.6 parts per million silver and 13,041 parts per million copper (Assessment Report 26632).

In 1987, E.W. Hayes completed a program of geological mapping and rock and silt sampling. In 1987 and 1990, programs of geochemical sampling, geological mapping, and ground geophysical surveys were completed by Avondale Resources. From 2000 through 2002, the area was prospected by M. Schau as the Pie 1-4 claims.