The Ruby Silver occurrence is located at 2135 metres elevation above sea level near the head of Mobbs Creek, 1 kilometre west of Tenderfoot Lake, in the Slocan Mining Division.

Regionally, the area lies within the Selkirk Mountains of southeastern British Columbia. The occurrence is within the Kootenay Arc, a curving belt of highly deformed metasedimentary and metavolcanic rocks which includes the Upper Proterozoic Horsethief Creek Group, the Upper Proterozoic to Lower Cambrian Hamill Group, the Lower Cambrian Badshot Formation, and the Paleozoic Lardeau and Milford groups. The volcano-sedimentary sequence is intruded by numerous Paleozoic to Mesozoic granitoid plutons.

The Tenderfoot Lake area is mainly underlain by the Mesozoic Mobbs Creek and Rapid Creek quartz monzonite stocks and the Early Jurassic Kuskanax monzonite batholith to the west. Grey quartz mica schist of the Broadview Formation along with marble, micaceous schist and amphibolite of the Paleozoic Milford Group form tightly folded rafts between the stocks and the batholith. The rocks have undergone contact and regional metamorphism to middle or upper greenschist facies (Geological Survey of Canada Bulletin 193).

The occurrence consists of a 60 to 120 centimetre wide brecciated quartz vein mineralized with galena, sphalerite, chalcopyrite, argentite and pyrite in a gangue of calcite and barite. The vein is at the contact between marble of the Milford Group and a quartz monzonite dike. Minor sulphide mineralization is also present within the marble and the wallrock is silicified. The vein has been explored with an adit which is now covered by a landslide. A 1.2 metre wide chip sample of the brecciated quartz vein exposed in a trench assayed 280 grams per tonne silver, 0.10 per cent lead and 0.38 per cent zinc (Assessment Report 916).

The occurrence may be on the same vein as the Grand Solo occurrence (082KSW113), one kilometre to the northwest.