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- Artikler 
Kongsberg is situated about 80 km west of Oslo at the river Numedalslågen. On p. 8 may be seen a list of the rocks, which occur in the region. All these rocks are of Precambrian age. Besides, there occur dykes of diabase, which are supposed to be of Post-Silurian age (Kongsbergdiabase). The Knuteformation is essentially composed of effusive rocks. Sedimentary rocks occur too, but it has not been possible to find any considerable Amount of them. Schists that may be supposed to be of sedimentarty origin occur between the benches of the effusive rocks, and often contain much mica and garnet. In the slides staurolite is generally to be seen.The supposed effusive rocks are likely to be andesites and dacites, which in their present metamorphic appearance may be characterised as amphibolites, granulites and gneisses. The Knuteformation may be divided into two groups, a light one and a dark one, these are given special names: The Barlinddalsgroup containing dacitic gneiss and the Oldenborggroup containing andesitic amphibolite and gneiss. The author has found breccias, which seem to prove that the Oldenborggroup is younger than the Barlinddalsgroup.