Nickel, copper and platinum group mineralization, Minneapolis Adit area

The mineralization occurs within a pegmatitic gabbro.

Major Minerals:

Pentlandite, pyrrhotite, chalcopyrite, pyrite

Minor Minerals:

Cubanite, nickelian mackinawite, violarite, millerite, marcasite

Trace Minerals:

Include bornite, cubanite, molybdenite, covelline, ilmenite, rutile, chrome spinel, braggite, cooperate, vysotskite, moncheite, platinum-iron alloys and native gold


The sulphides are interstitial to silicates. They form composite grains and globules with pentlandite cores surrounded by pyrrhotite and then chalcopyrite. Pyrrhotite carries flame-like exsolution bodies of pentlandite, and chalcopyrite has exsolved lamellae of cubanite. In serpentinized areas pentlandite and pyrrhotite are altered to millerite, violarite, nickelian mackinawite and marcasite accompanied by secondary magnetite. Braggite-vysotskite are the main platinum group minerals. Platinum-iron alloys and braggite are often euhedral whereas the other platinum groups minerals are complexly intergrown or replace each other.


Bow et al., 1982; Barnes and Naldrett, 1985; Criddle and Stanley, 1985