Massive serpentine, probably correlative with the Permian and older Shulaps Ultramafic Complex, is cut by several east trending and steeply south dipping diorite and quartz diorite dykes related to the nearby Cretaceous to Tertiary Bendor pluton. Irregular fissure veins with an average width of 15 centimetres occur most commonly along the dyke contact as well as branching into the serpentine. Streaks and pods of pyrite, arsenopyrite and chalcopyrite occur in sheared siliceous gangue with occasional quartz and calcite streaks. Oxidation is pronounced to over 15 metres depth.
One assay gave a high of 75.4 grams per tonne gold; another sample assayed 54.2 grams per tonne gold and 34.3 grams per tonne silver (Minister of Mines Annual Report 1937, page F9). From 1938 to 1940, 51 tonnes of ore was processed yielding 3732 grams of gold, 404 grams of silver and 199 kilograms of copper.
There are at least two adits and possibly a third. The Jewel prospect lies directly north of the Little Gem prospect (092JNE068) and some of the workings discussed in older reports may now be included in the Little Gem.