The Nat 4 occurrence is located on the northern end of Quadra Island, south of Granite Bay and east of Main Lake. The occurrence has been covered by 26 contiguous claims and several Crown grants owned by Lone Jack Resources Ltd.

Mine exploration on Quadra Island dates back to the 1880s. Some trenching and underground work were done in the early part of the century (Minister of Mines Annual Reports 1908 and 1910). A brief property examination was made in 1987 of the Great Gold showing and Epithermal zone by Lone Jack Resources Ltd. An extensive property exploration program was carried out in late 1987 and early 1988.

The northeastern half of Quadra Island is underlain by granitic rocks of the Juro-Cretaceous Coast Plutonic Complex. These are in fault and/or intrusive contact with Karmutsen Formation volcanic rocks and Quatsino Formation sedimentary rocks, both of the Upper Triassic Vancouver Group, along a northwest striking zone from Open Bay to Granite Bay. These units have a generally persistent strike of 150 to 155 degrees and dip subvertical to vertical. Block faulting has resulted in fault scarps which strike 145 and 180 degrees, with downthrown blocks to the southwest. Minor interbedded argillite and siltstone occur with the Quatsino Formation limestone. Younger basalt, andesite, diabase and felsite dikes are reported to cut all other rocks.

At the Great Gold showing, massive chalcopyrite occurs as discontinuous lenses near the contact of coarse crystalline limestone and grey silicified andesite and basalt. A coarse grained granite dike less than a metre in width occurs on the hangingwall side of one such lens and similar intrusions are present elsewhere. A 3.7-metre section (samples 5+10N,1+05E and 5+09N,1+04E) taken across this chalcopyrite lens averaged 5.04 grams per tonne gold (Assessment Report 17797). Twelve metres to the southwest, sample 4+99N,1+13E yielded 1.64 grams per tonne gold across 2.40 metres of chalcopyrite mineralization. The chalcopyrite occurs as discontinuous lenses that appear to be associated with grey silicified andesite. The tungsten-bearing mineral ferberite has been identified in andesite and adjacent quartz-albite-altered pyroxene granite.

Skarn mineralization, recognized by its variable pink to green colour, relative weight and hard surface, is found scattered along a zone of trenching. Petrographic studies of the skarn material shows the assemblage to consist of diopside, garnet and carbonate. Chalcopyrite, up to 10 per cent, and lesser pyrite and pyrrhotite often accompanies skarn mineralization. It has been interpreted that sulphide mineralization postdates skarn formation.

A 9.14-metre sample assayed 3.09 grams per tonne gold, 30.86 grams per tonne silver, 2.0 per cent copper, 0.1 per cent tungsten and 0.25 per cent zinc (Assessment Report 16142).

Five drillholes, totalling 604.95 metres, tested the occurrence in 1987 and 1988. The best intersection contained 1.25 grams per tonne gold, 2.8 grams per tonne silver and 0.22 per cent copper (Assessment Report 17797).