The Keiko property is underlain by the Weaver Lake Member of the Lower-Middle Jurassic Harrison Lake Formation comprised of basal andesitic to rhyolitic flows, which give way to bedded rhyolite tuffs, black argillite, siltstone and chert overlain by a massive andesite flow. On the north end of the property, the Harrison Formation is overlain by argillites of the Middle-Upper Jurassic Mysterious Creek Formation, and by the Triassic Camp Cove Formation which is comprised of interbedded greywackes, argillites, siltstone, chert, conglomerate and andesitic tuffs and flows.

A major fracture system along Harrison Lake is associated with quartz diorite and granodiorite intrusions of mid-Tertiary age, dated between 19 to 26 million years. A major fault structure apparently passes through Francis Lake dipping steeply to the west.

Mineralization is associated with an intense pyrite-silica and quartz-calcite vein system. The A 1 vein is a quartz-calcite vein which strikes 075 degrees with a near vertical dip and a length of 70 metres ranging between 20 centimetres to 5 metres in width. The vein hosts chalcopyrite, sphalerite, galena and pyrite.

In 1986, a composite chip sample yielded up to 614.1 grams per tonne silver, 0.335 gram per tonne gold, 0.046 per cent lead, 0.066 per cent zinc and 0.006 per cent copper (Assessment Report 15579).

The A 2 vein is comprised of a weakly brecciated quartz vein which strikes east-west and dips 30 degrees north with a 4 metre length and up to 50 centimetres in width. Samples across the vein assayed 3.5 to 89.9 grams per tonne silver, 0.016 to 0.099 gram per tonne gold, 0.02 to 0.059 per cent lead and trace to 0.033 per cent zinc (Assessment Report 15579).

The A 3 vein is a vertical quartz vein 30 centimetres wide, striking 110 degrees. A 30 centimetre chip sample assayed 57.6 grams per tonne silver and 0.075 gram per tonne gold (Assessment Report 15579).