The Slättberg mine consists of three separate mine fields, mined for nickel until the end of WWII. This sample here was collected on the most western field, which was the largest one. Each field consist of several mines but material on the dumps is somewhat mixed and can not be traced back for sure. The ore occurs in an altered amphibolite dike, with magnetite being the main mineral. Pyrrhotite, pyrite, chalcopyrite, bravoite, millerite, hematite, linnaeite have been reported.
Polished slab of the typical ore (11.5 cm wide). Note the amphibole and the chalcopyrite veins.
Needles of hematite with gray magnetite. Nic //, Obj. 20x, air, 100 µm bar:
Chalcopyrite, millerite/bravoite, magnetite. Nic //, Obj. 20x, air, 100 µm bar:
Millerite (Mll) and bravoite (Brv). Nic //, Obj. 50x, air, 50 µm bar:
The same with Nic +. 90° rotated, note the red internal reflections of the hematite:
Millerite with some bravoite, magnetite. Nic //, Obj. 20x, air, 100 µm bar:
The same, with Nic +:
Millerite and bravoite, magnetite. Nic //, Obj. 20x, air, 100 um bar:
The same with Nic +:
Magnetite, hematite, chalcopyrite, millerite (light yellow, left). Nic //, Obj. 20x, air, 100 µm bar:
Magnetite, hematite, chalcopyrite, millerite. Nic //, Obj. 20x, air, 100 µm bar:
Hematite, magnetite, chalcopyrite. Nic //, Obj. 20x, air, 100 µm bar:
Chalcopyrite, Nic //, Obj. 20x, air, 100 µm bar:
For further informations on the region these articles might be interesting:
Wickman: The Siljan Ring impact structure: possible connections with minor ores in its neighborhood. GFF.116.(1994).145-146.
Flood, B.: Slättberg Ni-gruvor. SGU Rapport Grb 63