The KMA showing is situated on the eastern slopes of Rainbow Mountain at the headwaters of Nineteen Mile Creek, east of Pemberton.
The claims lie along the western edge of a northwest trending roof pendant composed of metavolcanic rocks and minor argillaceous metasediments of the Lower Cretaceous Gambier Group. Pendant rocks dip moderately to steeply to the east and is interpreted to be an overturned sequence. The pendant is 4 to 5 kilometres wide, nearly 15 kilometres long and enclosed by the Jurassic to Cretaceous Coast Plutonic Complex.
The west side of the property is underlain by medium to coarse grained diorite of the Coast Plutonic Complex. Massive andesitic crystal tuffs crop out on the eastern portion of the property. The contact between diorite and andesitic tuffs is marked by a thin zone of felsic tuffaceous sediments and cherty mudstones. This contact is also marked by a northwest trending shear zone composed of chlorite schists.
The KMA showing consists of several types of mineralization. In the western parts of the property, quartz sweats and fracture-filling are mineralized with disseminated pyrite hosted in argillite. The Gossan Gulch area in the north and central part of the property averages 100 metres wide and 5 kilometres length. The hostrocks are sheared and pyritic sericite-chlorite schists, locally strongly oxidized into widespread goethite gossan. Several grab samples taken in 1982 by Stackpool Resources were enriched in barium, silver and gold (Assessment Report 21616). Sample 230003 yielded 76 per cent barium. Sample 230000 yielded 0.21 gram per tonne gold and 10.97 grams per tonne silver.
The Trench zone area has been the focus of most exploration activity. Trenching has exposed a shear zone in quartz sericite and chlorite schists which are locally silicified. The chlorite schist hosts a mineralized quartz stockwork. A silvery, sericite schist with finely disseminated pyrite has yielded consistent gold values of about 0.4 gram per tonne (Assessment Report 21616). A 1983 sample of siliceous sericite schist with sphalerite, covellite, pyrite and chalcopyrite in quartz veinlets assayed 12.9 grams per tonne gold, 6.5 grams per tonne silver, 0.08 per cent copper and 0.13 per cent zinc (Assessment Report 18804). Samples taken in 1988 contained up to 0.4 gram per tonne gold, 17.6 grams per tonne silver, 0.94 per cent zinc, 0.42 per cent lead and 0.16 per cent copper (Assessment Report 18804).
Anomalous base metal values up to 0.12 per cent zinc and 0.04 per cent lead are also present in pyritic quartz 'sweats' within argillite located west of the trenched area (Assessment Report 18804).
