The Twin 8 occurrence is located at an elevation of approximately 1390 metres on a southwest-facing slope, east of Homestake Creek and approximately 3.7 kilometres south-southwest of Samatosum Mountain.

Regionally, the area is in structurally complex metasedimentary and metavolcanic rocks of the Paleozoic (Lower Cambrian and older(?) to Mississippian) Eagle Bay Assemblage. The assemblage has a complex deformational history involving multiple stages of thrust faulting and folding during the Jurassic-Cretaceous periods , which produced strongly foliated and overturned rocks trending northwest and dipping northeast. These Paleozoic rocks are intruded by mid-Cretaceous granodiorite and quartz monzonite (such as the Baldy Batholith approximately 30 kilometres to the north of the occurrence), and Neogene quartz-feldspar porphyry, basalt, and lamprophyre dikes. These are all locally overlain by Miocene plateau lavas, now represented in the area by occasional erosional remnants.

The Eagle Bay Assemblage rocks include andesitic volcanic rocks of the Devonian to Mississippian Foghorn Mountain unit, greenstone and greenschists rocks of the Lower Cambrian Johnson Lake unit and Lower Cambrian mudstone, siltstone, shale, fine clastic rocks, limestone, and calcareous sedimentary rocks.

Locally, as defined by diamond drilling, variably quartz-carbonate-fuchsite–altered mafic volcanic flow and breccia hosts stockwork quartz veining with disseminated to semi-massive and massive pyrite and disseminated to blebby chalcopyrite, tetrahedrite, and galena within the veins.

In 1987, drillhole Twin 8, located near the former Twin 2-3 and Kamad 8 claim boundaries, yielded two mineralized intercepts of 0.17 gram per tonne gold, 20.2 grams per tonne silver, 0.28 per cent copper, 2.23 per cent lead and 1.61 per cent zinc over 1.3 metres and 0.37 gram per tonne gold with 2.0 grams per tonne silver over 1.5 metres (Assessment Report 16774).

In 1989, a nearby drillhole (K89067), located on the northeast corner of the Kamad 8 claim, is reported to have intercepted Rea zone stratigraphy yielding 0.05 gram per tonne gold, 9.0 grams per tonne silver, 0.21 per cent copper, 1.20 per cent lead and 1.26 per cent zinc (Assessment Report 37434).

In 1991, a nearby drillhole (T91038) intersected the Silver zone horizon, consisting of pyritic sediments and a large fault zone, yielding 0.18 gram per tonne gold, 7.4 grams per tonne silver, 0.042 per cent copper, 0.115 per cent lead and 0.227 per cent zinc over 5.3 metres (42.4 to 47.7 metres down-hole) of the pyritic sediments and 3.65 grams per tonne gold over 0.8 metre of the fault zone (Assessment Report 22389).

Also at this time, another drillhole (K91082) on the former Kamad 8 claim is reported to have yielded 0.41 gram per tonne gold over 0.2 metre (Assessment Report 37434).

Work History

The area has been explored in conjunction with the nearby Twin Mountain (MINFILE 082M 020), Twin 3 (MINFILE 082M 276) and K-7 (MINFILE 082M 277) occurrences and a complete exploration history can be found there.