The graphite schists in the Gjerstad-Kragerø area and their graphite potential, Southern Norway

Abstract

The purpose of this report is to present the available data regarding the graphitic schists in the Gjerstad-Kragerø area and to make the data available for explorers and municipal land use planners.The graphite schists that occur southeast of Lake Vegard in the Gjerstad, Kragerø and Tvedestrand area have an average content of graphitic carbon of 2.77 %. Rocks from the abandoned Bjørnås mine have contents up to 33 %. The investigated area comprises a large area with low grade graphitic rocks and there is an almost complete airborne geophysical covererage with EM and MAG data. In thin section the typical modal content of graphite is about 8%