The Donner occurrence is located at an elevation of 600 metres, approximately 500 metres northwest of the northern end of Donner Lake.

The area is underlain by Upper Triassic Vancouver Group rocks consisting of Karmutsen Formation basalts overlain by Quatsino Formation limestone. These are intruded by the Jurassic Island Plutonic Suite consisting dominantly of quartz diorite with lesser diorite and granodiorite. A number of skarn showings are scattered within all three major rock units and at their contacts. Several of the skarns within the Karmutsen basalts are conformable, occupying highly amygdaloidal flow tops.

The skarns consist primarily of magnetite and garnet with strong concentrations of epidote in the surrounding basalts. Some contain, pyrite, chalcopyrite and sphalerite. Diamond drill core shows chalcopyrite occurring in patches, vesicles and veins within highly silicified basalts.

In 1973, rock sampling yielding up to 1.0 gram per tonne gold, 0.05 per cent zinc, 4.6 per cent copper, 0.006 per cent nickel, 0.05 per cent chromium and 4.3 per cent titanium. Drilling the same year yielded up to 0.07 per cent copper over an unknown length (Assessment Report 4972).

In 1978, a 2 metre chip sample (209) assayed 15.8 grams per tonne silver and 2.79 per cent copper; while a 1 metre chip sample (211), from the same area, yielded 0.27 gram per tonne gold, 15.8 grams per tonne silver and 6.75 per cent copper (Assessment Report 7410).

In 1979, drill intercepts yielded up to 0.391 per cent copper and 4.5 grams per tonne silver over 4.5 metres (Assessment Report 8037).

In 1963, Mastodon-Highland completed a program of geological mapping and a ground magnetometer survey on the area as the Gam claims. During 1973 through 1977, W. Babkirk prospected the area as the Donner and Heber claims. In 1973, three surface diamond drill holes, totalling 95.0 metres, were completed. In 1975, two more drill holes, totalling 60.6 metres, were completed to the west but only encountered un-mineralized intrusives. In 1978, Mont Alta Projects Ltd. completed a program of rock sampling and ground geophysical surveys on the area as the Donner Lake property. In 1979, CON-AM Resources optioned the property and completed a program of geological mapping, rock sampling, a ground magnetometer survey and five diamond drill holes, totalling 166 metres.