The Nan occurrence is located west of Harris Creek, in its northern head waters.

The area is underlain by a series of basaltic flows and related pyroclastics of the Karmutsen Formation and is overlain by, or interbedded with, limestone of the Quatsino Formation; both formations belong to the Upper Triassic Vancouver Group. Andesite to rhyolite tuffs and breccias, with minor intercalated greywacke and argillite, of the Lower Jurassic Bonanza Group overlie the Upper Triassic rocks. Intruding this stratigraphic assemblage is the Early to Middle Jurassic Island Plutonic Suite (formerly the Island Intrusions) of monzonite to diorite composition.

Outcrops on the Nan property consist of a thick sequence of volcanic rocks, generally andesite in composition, interbedded with limestone. Magnetite-chalcopyrite mineralization occurs at several points where skarn has developed along the lower limestone-volcanic contact. In all instances the skarn has developed where east or northeast trending faults cut the contact, and in places the mineralization extends for a limited distance along the faults. The skarn consist of garnet, epidote, diopside and calcite. Magnetite is the principal economic mineral present and contains erratic amounts of chalcopyrite. Minor amounts of sphalerite and hematite have also been noted.

Mineralization occurs in three separate areas. At the first, along road H.C. 1821 and immediately to the south, magnetite and erratic chalcopyrite mineralization are exposed at 4 points within an area measuring 60 by 30 metres. Maximum visible exposed thickness of the magnetite is about 1.2 metres. A selected sample from here assayed 1.0 per cent copper and 21.5 per cent iron (Philp, 1969).

The second region where mineralization occurs is 400 metres southwest of the first. Here, a series of epidote-magnetite skarn boulders occur along a logging road and appear to be near their source.

The third region lies approximately 600 metres west of road H.C. 1820. Garnet skarn is developed along the hanging wall and footwall of a northeast trending fault which is exposed in a near vertical face in a southeast flowing creek. A series of magnetite lenses, containing minor chalcopyrite, outcrop intermittently and are indicated by magnetics for a distance of almost 100 metres, following a limestone-volcanic contact. Minor sphalerite was noted in the limestone along the hanging wall of the fault.

In 1971, Lucky Strike Mines completed a program of geological mapping, soil sampling and a ground magnetometer survey on the CW and LG claims.