The Treasure Mountain region is underlain by northwest striking, moderate to steeply southwest dipping volcanic and sedimentary rocks of the Lower-Middle Jurassic Dewdney Creek Formation (Ladner Group) and Lower-Upper Cretaceous Pasayten Group, intruded by numerous dikes and sills. The Dewdney Creek Formation comprises volcanic rocks and a minor amount of sediments and consists of tuff, breccia and agglomerate with interbedded argillite and conglomerate. The Dewdney Creek Formation is considerably altered; pyrite is commonly present and many outcrops are rusty. The Pasayten Group includes predominantly arkose, argillite and conglomerate. Locally, the two sequences are separated by a northwest striking, northeast dipping fault, but in large part are conformable.

Several faults occur. Two faults cross the southwest part of the region and strike east and dip steeply south, but one splay of one fault dips north. The more northerly of these two faults, the Indiana fault, hosts the Blue Bell and possibly the Indiana (092HSW022) and Summit (092HSW023) occurrences. The southern fault, the Queen Bess fault, hosts the Queen Bess (092HSW021) occurrence. These two faults diverge to the west from the Treasure Mountain fault and contain subparallel splays separated by shattered rock. The Queen Bess fault splits into two branches that diverge toward the west.

Mineral occurrences in the area are hosted in the Treasure Mountain fault and in and near subsidiary faults, and comprise one or more quartz-carbonate veins or stringers that branch and split and vary considerably in width and attitude (see Treasure Mountain, 092HSW016).

The Blue Bell occurrence is underlain by northwest striking (315 degrees), moderate to steep (65 degrees) southwest dipping volcanic and sedimentary rocks of the Dewdney Creek Formation intruded by numerous sills and some dikes ranging from diorite to gabbro in composition. Four faults cross the area: Indiana, Queen Bess, Ridge, and the trace of the Treasure Mountain fault, and cut argillite, agglomerate, tuff, breccia and conglomerate units.

The most northerly fault, the Indiana fault, has a variable strike ranging between 085 degrees to 110 degrees with dips between 70 to 85 degrees south. Adits and opencuts have explored this fault for 243 metres. The fault contains irregular, discontinuous quartz-calcite veins 2 to 30 centimetres wide, and a stringer zone 30 centimetres wide; some gouge is also evident. The veins are well mineralized with pyrite, sphalerite, argentiferous galena, some arsenopyrite and pyrrhotite and minor chalcopyrite; but the stringer zone is sparsely mineralized. Some shearing is evident parallel to the veins. Epidote and sericite occur disseminated throughout the vein zone and along vein selvages. A sample across 0.3 metre in a diamond-drill hole intersection assayed 726.73 grams per tonne silver, 4.4 per cent lead and 10.7 per cent zinc (Assessment Report 11455).

In the central part of the Blue Bell claim (Lot 132), the Queen Bess fault strikes west-southwest and appears to continue to the west to the Queen Bess occurrence (092HSW021). The fault hosts quartz veining a few centimetres in width. Small amounts of sulphides accompany the quartz which are locally manganese stained.

In the north, a recently discovered adit (adit E) on the Summit No. 2 claim (Lot 130), is developed on a 15 centimetre wide mineralized fault zone. A select grab sample from dump material assayed 233.44 grams per tonne silver, 6.11 per cent lead, 12.34 per cent zinc and 0.3 per cent copper (Dewonck, 1987).

The Ridge fault in the east is a splay off the Treasure Mountain fault, and has not been tested. The approximate trace of the Treasure Mountain fault in the south has been drill tested from an outcrop of a sill, but only unmineralized stringers of quartz were intersected.

Past work comprised some underground development.