Applied Mineralogy of the Suurikuusikko Refractory Gold Deposit, Northern Finland

摘要

The Suurikuusikko gold deposit was discovered in 1987 in western Finnish Lapland, 54 km NNE from the town centre of Kittila in the volcanic belt of Central Lapland. It is hosted by tholeiitic basalts in a graphite-bearing albitite breccia. The ore is located in subvertical shear zones characterised by strong albitisation, carbonatisation and sulfidisation. The ore minerals consist of arsenopyrite, pyrite, chalcopyrite, sphalerite, tetrahedrite, bournonite and rutile. Small amounts of pyrrhotite, gersdorffite, jamesonite, bomite, gudmundite, tetrahedrite, stibnite, kermesite, berthierite and native Sb are also present. Gold occurs as invisible and as 1 - 2 mu m size inclusions in arsenopyrite and pyrite, on their grain boundaries and in fractures.