The A-1 occurrence is located at an elevation of approximately 1200 metres on an east-facing slope, west of Mamit Lake and east of Antler Lake.
The area lies near the eastern border of the Upper Triassic to Lower Jurassic Guichon Creek Batholith. The area is underlain by coarse-grained quartz diorite to granodiorite of the Border phase, which grades westward to younger, medium-grained Guichon variety granodiorite of the Highland Valley phase of the batholith. To the east the intrusive rocks are in contact with sedimentary and intermediate volcanic rocks of the Upper Triassic Nicola Group. The contact strikes north and dips steeply and is marked by high-grade metamorphism.
Locally, minor amounts of chalcopyrite occur in minor open fractures associated with chlorite and carbonate and in wider siliceous fracture zones. Pyrite, magnetite and specular hematite are also reported in the area. Drilling on the A-1 zone is reported to have yielded 0.13 and 0.17 per cent copper over 0.39 and 0.66 metre, respectively, in hole A-1-1; 0.456 and 0.167 per cent copper over 1.8 and 2.1 metres in hole A-1-2; 0.10 per cent copper over 1.4 metres in hole A-1-3 and 0.528 per cent copper over 10.8 metres in hole A-1-4 (Property File – 843263).
Another zone of mineralization, referred to as the South Diorite zone, is located approximately 650 metres southeast of the previous zone, and comprises north-northeast–trending and near-vertical–dipping fractures hosting minor magnetite, pyrite and chalcopyrite. A drillhole (DDH-9), located east of this zone and near the west shore of Mamit Lake, is reported to have yielded 0.47 per cent copper over 22.8 metres (Property File – 843263).
Other zones of copper mineralization are reported to the north-northwest of the A-1 occurrence.
Work History
Copper mineralization was first discovered in the area around 1914 and subsequently several hand trenches and two or more shallow shafts were excavated.
During the late 1960s and early 1970s, program of geological mapping, geophysical surveys, trenching and diamond drilling were completed on the area as the MLM claims.
A complete exploration history of the area can be found in the nearby Rod (MINFILE 092ISE071) occurrence.
