The McPhail deposit is located 10.5 kilometres east-southeast of Vernon and adjoins the Monashee mine area (082LSE001).
In 1900, the property, comprising the Rossland, Mascot and Evening Star claims, was optioned by the Cherry Creek Gold Mining Co. Ltd. During 1902-1904, drifts, raises and adits were developed. The McPhail tunnel was 52 metres long with 2 raises of 7.6 and 15 metres respectively, the Evening Star was 70 metres long and an unnamed tunnel was about 91 metres long with a raise 23 to 30 metres long. In 1903, a 5-stamp mill operated for a short period. The company also held the Monashee property at this time so the source of the mill feed is questionable. A new crosscut was started on the Rossland in 1914. By 1915, all work was suspended. At this time the crosscut on the Rossland claim, which did not intersect the vein, was 240 metres long. The Monashee Mines Syndicate Ltd. acquired the property in 1933. In 1989, a geochemical survey and rock sampling were completed.
The area is underlain by metamorphosed limestone and subordinate argillite, siltstone, quartzite and green tuffaceous volcanics of the Devonian to Triassic Harper Ranch Group. A lobe of granodiorite or quartz diorite of the Jurassic Nelson Intrusions extends onto the Evening Star No. 2 and No. 4 claims. A lamprophyre dike is present near the north boundary of the No. 4 claim. Some skarn is present near the granite contact with the limestones. Bedding indicates that the sedimentary sequence strikes northwest and dips northeast.
Seven quartz veins occur over a 122-metre interval, of these 4 veins are narrow and relatively unmineralized. Three subparallel veins, explored by tunnels, are 30 to 91 centimetres wide, trend 310 degrees and dip 40 to 70 degrees southwest. The veins are hosted in sediments and are mineralized with fine-grained pyrite, galena, sphalerite and minor chalcopyrite.
The McPhail vein can be traced on surface for 76 metres. The vein is 60 to 91 centimetres wide on surface but underground is up to 2.4 metres wide. Mineralization consists of scattered bunches of very fine grained pyrite, galena and sphalerite and minor chalcopyrite and tetrahedrite.
A second vein, 30 metres north of the McPhail vein, is explored by a 91-metre tunnel. The vein is at least 60 centimetres wide locally and is explored by a vertical raise about 24 metres from the face. In 1973, a sample across 60 centimetres of this vein, taken about 9 metres from the portal, assayed 4.46 grams per tonne gold and 27 grams per tonne silver (Assessment Report 4771). Selected samples have higher grades.
On the Evening Star claim, which adjoins the Rossland claim on the northwest, the 70-metre adit was driven on a quartz vein which strikes southwest and dips near vertical. The vein averages 60 centimetres in width and is mineralized with pyrite, galena and chalcopyrite. A chip sample taken in 1973 across 91 centimetres near the portal assayed 26 grams per tonne gold and 99 grams per tonne silver (Assessment Report 4771).
Reconnaissance soil sampling in 1973 indicated the possibility of silver-bearing veins near the north boundary of the claims which may represent extensions of the veins explored by the adits.