Melkedalen grube i Ofoten. Søndre Ofotens malmforekomster I.

Abstract

Melkedalen copper mine is situated at latitude 68 degrees 15 N, in the district of Ofoten, Northern Norway. It has formerly been mined only for chalcopyrite, but actually iron pyrites and sphalerite are equally important constituents of the ore. The whole district has been subject to considerable sulphidic mineralization, with numerous deposits of different types. The reason why Melkedalen is here teated in a separate paper, is because its genetic development seems to be quite evident. The deposits may briefly be characterized as an hypothermal, quartz-bearing breccia vein along a fault fissure in dolomite, the ore minerals being mainly deposited by replacement. The latter part of the paper, devoted to historical and technical objects, will not be referred to here, because it has only local interest. The mine was worked by several British companies, intermittently between the years 1899-1912, with little succes, however, mainly on account of the complete failure of the concentration plant. The Melkedalen area is composed of a thick series of homogenous mica schists, metamorphosed regionally in the epidote-amphibolite facies.