Thirty minerals found in cavities of the Oslo Region biotite granite are described in some detail, with optical, crystallographical, and spectrochemical data. The sequence of crystallization is determined for the most common minerals. The cooling history of the granite magma and the composition of the magmatic volatiles are briefly outlined. The decomvosition of titanite by the action of late hydrothermal, siliceous solutions, and some geochemical aspects of the common association anatase-synchysite are discussed.
Cavity minerals from the Permian biotite granite at Nedre Eiker Church