This is a detailed description of a nickel deposit near Goward in the Timagami Provincial Forest 300 miles north of Toronto, Ontario. The general geology of the Cuniptau mine is comparable to that of many other mining areas of that section of Ontario. Lying on the deeply eroded surface of a basement complex is a great thickness of Keewatin lavas. After their extrusion they were folded, faulted, and intruded by peridotite. A long period of alteration and erosion followed, before the final intrusion of many small Keweenawan dikes. It is concluded that the Keweenawan intrusives had no part in the mineralization at Cuniptau mine. This is a case where post-magmatic solutions deposited the copper and nickel sulphides. The important and abundant nickel-bearing sulphide is the secondary nickel sulphide violarite, which may make this nickel deposit one of the first mined in which secondary enrichment has played an important role.

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