The Rollo prospect is situated 1 to 1.5 kilometres southwest of the summit of Nickel Plate Mountain, 2 to 2.5 kilometres east- northeast of Hedley.

The region, northeast of Hedley, is underlain by a sequence of interbedded limestone, siltstone, and argillite of the Upper Triassic Hedley Formation (Nicola Group), which is intruded by diorite and gabbro stocks, dykes and sills of the Early Jurassic Hedley Intrusions.

A shear zone near the northeast corner of the Horse Fly claim strikes 100 degrees and dips 70 degrees south. The zone has been traced on surface for 90 metres and has been intersected by diamond drilling to a depth of 120 metres. The 0.15 to 0.90-metre wide zone cuts sediments and diorite, and is mineralized with arsenopyrite, pyrrhotite, pyrite, chalcopyrite and sphalerite in a gangue of silicified material with minor calcite and quartz. Pyrrhotite, arsenopyrite, with lesser chalcopyrite and sphalerite, occur as irregularly-shaped massive pods over a distance of 30 metres at the east end of the shear zone. Two selected samples from surface assayed 23.2 and 38.4 grams per tonne gold (Assessment Report 10801). A 1.6-metre section of massive pyrrhotite, with minor chalcopyrite and arsenopyrite, intersected 14 metres below surface, assayed 16.9 grams per tonne gold and 33.9 grams per tonne silver (Assessment Report 10801, hole HF-2).

A second shear zone, 0.3 to 0.45 metres wide, occurs in garnet skarn 30 metres to the south. The zone strikes 105 degrees for 20 metres and contains arsenopyrite, pyrrhotite, pyrite and chalcopyrite.

A large inclusion of massive garnetite in diorite outcrops on the Rollo claim over a 60 by 20 metre area, 430 metres west-southwest of the shear zones. The garnetite contains lenses and irregular masses of coarse calcite up to 1 metre across. Mineralization is sporadic and consists of chalcopyrite, with minor pyrrhotite, as stringers, small masses and disseminations.

Various old workings on the Rollo Crown-granted claim to the south, expose limestone and calcareous sediments intruded by diorite sills and locally altered to garnet and epidote garnet skarn over an east-west distance of 300 metres. The skarn is locally mineralized with lenses and bands of massive arsenopyrite and pyrite up to 0.6 metres in width. Arsenopyrite and lesser pyrrhotite, pyrite and chalcopyrite also occur as disseminations in the skarn. Four selected samples of arsenopyrite from the old workings assayed 19.9 to 61.0 grams per tonne gold and trace to 14 grams per tonne silver (Minister of Mines Annual Report 1937, page D13).