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 (092HSW020) and possibly the Indiana 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 Indiana occurrence is underlain by volcanic sandstone, conglomerate and argillite of the Dewdney Creek Formation intruded by Late Cretaceous-Tertiary diorite-basalt-dacite dikes. The rocks strike 330 degrees with vertical dips. The Indiana fault strikes through the area at 075 degrees and dips 70 degrees south. It continues to the east onto the northern part of the Blue Bell occurrence (092HSW020) and to the west to the Summit occurrence (092HSW023).

The fault in the Indiana area is nearly 1.2 metres wide at the adit portal but narrows considerably to the west. It contains several narrow quartz-carbonate stringers separated by gouge and by bleached and pyritic wallrock. The veins are typically irregular and discontinuous and are mineralized with variable amounts of argentiferous galena, sphalerite, pyrrhotite, arsenopyrite, chalcopyrite and pyrite. Epidote and sericite occur disseminated throughout the vein and in vein selvages. Limonite (mainly goethite) occurs in fractures cutting the veins and sulphide mineralization. Petrographic examination revealed inclusions of proustite and tennantite in pyrrhotite and also identified pyrargyrite. Trenching has exposed a quartz-carbonate vein at the Indiana adit and extends 75 metres southwest. A channel sample across 1.4 metres assayed 0.2 per cent copper, 8.11 per cent lead, 6.85 per cent zinc, 647.54 grams per tonne silver and 0.03 gram per tonne gold (Assessment Report 18111).

Recent work has extended the strike length of the Indiana structure to 799 metres where it has been exposed by trenching for over 300 metres. The structure ranges from 0.7 to 2.9 metres in width and extends over a vertical range of 106 metres. A weighted average of surface channel sampling of six zones on the Indiana structure yielded a grade of 490.20 grams per tonne silver, 5.5 per cent lead, 2.6 per cent zinc and 0.68 gram per tonne gold over a 135 metre length and a 1 metre width (Annual Report-Schellex, 1989). A grab sample from the Indiana adit yielded 0.3 per cent antimony (Dewonck, 1987).

Past work comprised some underground development.