The Rob occurrence is located 9.7 kilometres due west of Cowichan Lake on Horse Creek.
The property was initially staked as the Southern Cross in the 1930's to cover a skarn zone mineralized with copper and magnetite. The property was intermittently explored between 1941 and 1960. In 1960, a test run of 4665 tonnes was taken from open pits, producing 61,929 kilograms of copper. Exploration commenced again in 1969 continuing until 1972. No further work was undertaken until 1986 when the skarn mineralization was tested for gold content.
The area is underlain by sedimentary and volcanic rocks of the Upper Triassic Vancouver Group and the Lower Jurassic Bonanza Group. The Vancouver Group comprises limestone, calcareous siltstone, shale, cherty limestone and chert of the Quatsino Formation and pillow basalt, tuff, breccia and minor flows of the Karmut- sen Formation. The Bonanza Group consists of basaltic to rhyolitic tuff, breccias and flows with minor greywacke and argillite. These have been intruded by Early to Middle Jurassic Island Plutonic Suite granitic rocks and feldspar porphyry dykes of unknown affinity. The area is structurally complex, containing several sets of faults with evidence of drag folding.
Skarn mineralization is hosted in Quatsino Formation limestone and porphyritic andesite of the Bonanza Group near contacts with diorite intrusions and feldspar porphyry dykes.
Three types of skarn occur on the property:
1) Ilvaite-garnet-epidote-magnetite in calcium-rich rocks
2) Epidote-actinolite-garnet in less calcium-rich rocks (andesite
3) Laminated pyrrhotite-magnetite-chalcopyrite All three types contain chalcopyrite as erratic disseminations and as small masses along fractures and veinlets. Hematite, bornite and lesser pyrite and pyrrhotite are occasionally present. Malachite and azurite occur on fractures. Chalcopyrite and pyrite also occur in volcanic rocks, usually associated with epidote and quartz-filled amygdules. Chalcopyrite and galena were observed in limestone at one locality, and chalcopyrite has been noted in sheared diorite.
The main skarn zone, conformable with regional strike (strikes north-northwest, dips steeply south) is lenticular in shape and covers an area 610 by 152 metres. Skarn mineralization is exposed at widely scattered locations in creek gullies and along roads on the property. The best exposure is at the small pits developed in 1960 by Nadira Mines Ltd. The weighted average of 90 chip samples taken over a total of 235 metres was 1.73 per cent copper (ranging from 0.1 to 5.6 per cent) and 6.86 grams per tonne silver (Assessment Report 2115). A sampling program undertaken to assess the gold content of the skarns resulted in low values.