Kobberforekomster på Straumsheia.

Abstract

The deposits have been known for more than 250 years, and have been worked off and on during that period of time with no great success. The total production has probably not been more than one hundred tons of copper. As shown in figs. 1 and 2 they are situated in an area consisting of supracrustal rocks which are probably an extension of the Telemark formation found to the north. The supracrustal rocks, quartzites and amphibolites, contain very numerous irregular lumps and dykes of granite and pegmatite. Pegmatites have been mined for copper in Amalie gruve and Gamle gruve. The following minerals have been found: Plagioclase, quartz, biotite, delessite, garnet, magnetite, apatite, yellow beryl, brookite, epidote, fluorite, chalcocite, bornite, malachite, chrysocolla, uraninite, kasolite, uranotil. The origin of the cyprin (green vesuvianite) from Straumsheia is uncertain, it does not belong to the paragenesis of the cupriferous pegmatites. Brookite and kasolite are new species for Norway.