The Cub occurrence is located near the mouth of the Tootsee River in the Cassiar Mountains of northwestern British Columbia, about 130 kilometres west-southwest of Watson Lake, Yukon.

Vein and replacement mineralization occur in sheared Cambrian-Ordovician Kechika Group phyllites, siltstones and limestone in an embayment on the east side of the quartz monzonitic Early Cretaceous Cassiar batholith. The trend of mineralization, foliation and bedding are roughly conformable and dip moderately southwest. Greenstone metavolcanics or sills occur in the sequence. Mineralization occurs as disseminations, stringers and laminations of galena, sphalerite, pyrite and siderite in silicified, partly oxidized zones in phyllite or limestone. A diamond-drill hole intersection of about 1.5 metres assayed 32.6 grams per tonne silver, 2.64 per cent lead, and 4.94 per cent zinc (Assessment Report 13376). See the Amy occurrence (104O 004) located 960 metres south for related work history.

In 1977, the Cub claims adjoining the Amy deposit (104O 004) were located. DuPont of Canada conducted geological and geochemical surveys on the Cub property in 1979, primarily to evaluate skarn zones with values in tungsten and molybdenum. In 1981 and 1982, Morbaco Mines Ltd., a successor to Fosco Mining Ltd., optioned the Cub property and conducted geochemical surveys and limited bulldozer trenching. In 1984, Sovereign Metals Corporation carried out exploration on the Cub property to test for potential extensions to the Amy deposit and to locate the source of high-grade float. Eight diamond-drill holes comprising 439 metres were completed.