Kiskamavaara is a pyrite-dominated cobalt resource, historically estimated at 3.2 Mt at 0.065% Co and 0.37% Cu. It is widely recognized that classification as “IOCG-style” has been too broadly applied, making deposit classification alone ambiguous to determine the relationship between mineralisation processes and deposit genetics. At present it is subeconomic. The host rocks in the Kiskamavaara area comprise Svecofennian supracrustal rocks of the Porphyrite group, consisting of tuffites, intermediate low Ti basalts and andesites overlain by quartzite. Extensive hydrothermal alteration is common along both brittle–plastic and plastic structures in the Kiskamavaara deposit. The alteration minerals generally indicate a zoning pattern with fault proximal scapolite + biotite alteration, and carbonate + albite in distal parts of the deposit. Strong K-feldspar alteration in Kiskamavaara is prominent in 250–300 m wide zones proximal to mineralisation. Most of the mineralisation occurs in a fragmental breccia of intermediate composition and is present as three individual mineralisation lenses.

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