A New Rock

Abstract

DURING my visit last summer to Lake Sagvand, in the Balsfjord, near the city of Tromso, I discovered a new enstatite-bearing rock, which forms entire little hills. It is composed of light yellow-green enstatite, mixed with magnesite. The magnesite, which is entirely free from lime, is partly white, partly dirty grey in colour, in which latter state it contains a little oxidulated iron, and appears then distinctly crystalline, with rhomboidal planes of cleavage. The rock is greatly interspersed with little grains of chromite, which are found in the enstatite as well as the magnesite. Here and there small grains of pyrite also appear. The substance is perfectly free from olivine, at all events neither olivine nor serpentine has been discovered under microscopical analysis.