The Fidelity mine is in a basin near the headwaters of Horsefly Creek, which flows into Trout Lake. The basin is on the southwest side of Silver Cup Ridge, between 1828 and 2286 metres in elevation. The Fidelity claim group consists of the Fidelity (L.7269), Annie E. (L.7268), Nipissing (L.7270), Spokane (L.7272), We Two (L.7273) and Bosun (L.7271) claims and several small intervening fractions.

The Fidelity group was owned and developed by the Canadian Lardo Mining and Development Company in the early 1900s. There are two adits. The upper adit is 61 metres long and has several crosscuts driven to the north and south of it. It follows a relatively flat lying vein. The lower adit was driven for approximately 90 metres. It cuts a series of black slates and carbonaceous quartzites that were found to be much faulted. The faults and shears contained small amounts of sulphide but there was little of economic significance. The property was operated under lease by Lamphere & Company in 1912 and 1913. Ore was mined from a flat-lying body located near surface, to the north of the main drift. The total tonnage is uncertain as there are inconsistencies in the figures. However, several shipments were made, including the following: 22.7 tonnes grading 7.54 grams per tonne gold, 1807 grams per tonne silver, 45.1 per cent lead and 1.8 per cent zinc; 21.6 tonnes containing 6.17 grams per tonne gold, 2400 grams per tonne silver and 61.2 per cent lead; and 9.1 tonnes assaying 8.91 grams per tonne gold, 1992 grams per tonne silver and 51.4 per cent lead. The zinc content of the last two was trace only (EMPR AR 1914-K308/9). Some of these shipments may be missing from the attached production report. The property was acquired by J. Gallo and Associates in 1927, after lying idle since 1918. They drove a short crosscut to the south from the east end of the upper adit.

The property was explored by Great Basin Petroleum Limited in 1981. It prospected the area and traced the vein about 300 metres north from the adit to a broad zone of fracturing and silicification, containing abundant quartz-carbonate stringers, in Horsefly Creek. The company conducted soil and silt sampling programmes and also diamond drilled three holes, two from above the main showing in Horsefly Creek and one above the main adit. Recovery was poor and the resulting assays were not considered to be significant. Quattro Resources Limited acquired the Fidelity group in the late 1980s and, after an airborne geophysical survey and initial surface evaluation in 1987, issued a prospectus in July of the following year. The Trout Lake area is underlain by a thick succession of sedimentary and volcanic rocks of the Badshot Formation and Lardeau Group near the northern end of the Kootenay arc, an arcuate, north to northwest trending belt of Paleozoic and Mesozoic strata that is now classified as a distinct, pericratonic, terrane. The arc rocks are bordered by Precambrian quartzite in the east and they young to the west, where they are bounded by Jurassic-age intrusive complexes. They were deformed during the Antler orogeny in Devonian-Mississippian time and were refolded and faulted during the Columbian orogeny, in the Middle Jurassic. A large panel, the "Selkirk allochthon", was later offset to the northeast by dip-slip motion along the Columbia River Fault.

The Badshot Formation is composed of a thick Cambrian limestone that is a distinctive marker horizon in the Trout Lake area. It is underlain by Hamill Group quartzite and it is overlain by a younger assemblage of limestone, calcareous, graphitic and siliceous argillite and siltstone, sandstone, quartzite and conglomerate, and also mafic volcanic flows, tuffs and breccias, all of which belong to the Lardeau Group. The rocks are isoclinally folded and intensely deformed, but only weakly metamorphosed. They occur as intercalated beds of marble, quartzite and grey, green and black phyllite and schist. Fyles and Eastwood (EMPR BULL 45) subdivided the group into six formations (Index, Triune, Ajax, Sharon Creek, Jowett and Broadview) of which the lowermost (Index) and uppermost (Broadview) are the most widespread. The Triune (siliceous argillite), Ajax (quartzite) and Sharon Creek (siliceous argillite) are restricted to the Trout Lake area. The Jowett is a mafic volcanic unit.

The Fidelity claims straddles a major northwest trending fault that runs down the axis of Silver Cup Ridge. The rocks on the northeast (hanging wall) side of the fault are composed of green, grey and black phyllites of the Index Formation and black siliceous argillites of the Triune Formation. Rocks on the footwall side are predominately grey, gritty, phyllites of the Broadview Formation. There are diorite bodies intruding the Index Formation strata. The rocks are deformed, folded and intensely schistose. They commonly display parasitic folds with shallow northwesterly plunging axes. The cleavage strikes to the northwest and dips moderately to steeply to the northeast, as it does throughout the Silver Cup Ridge area. The Fidelity Fault truncates the west limb of an antiform, and strata near the fold crest are shallow dipping. Some of the less structurally competent rock units may also have been rotated downhill as a result of hillside creep. According to Gunning (GSC MEM 161), the vein may project towards one of the intrusions and there may be concentrations of ore beneath or west of the dyke.

There are two veins on the property. The main vein is exposed in the upper adit. It is from 1.52 to 2.4 metres wide and consists of quartz and carbonate sparingly mineralized with pyrite and galena. The mineralized section is 0.46 metre wide and contains several sulphide stringers ranging in width from 0.08 to 0.18 metre. It is conformable with the enclosing schists and has northwest trending strike and a shallow to moderately easterly dip. The principal ore-shoot is a galena-rich "streak", from 0.1 to 0.15 metre in width, between the main vein and the hanging wall. The high-grade shoot material contained fine-grained galena with a silky texture and some antimony but very little zinc. The second vein is narrow and composed of quartz with minor pyrite and galena, and has a more northerly strike. It cuts the formation rocks at a low angle.

Great Basin Petroleum Limited prospected the area and sampled a 5.0 metres wide section, containing quartz and carbonate stringers, in silicified rock in Horsefly Creek. The zone assayed 1.1 grams per tonne gold, 4.46 grams per tonne silver and small amounts of lead and zinc. It is on strike with the main workings, which show a flat lying vein that may have hanging wall, and possibly footwall, imbricate veins associated with it.