Cathodoluminescent Features and Raman Spectroscopy of Miocene Hydrothermal Bio-mineralization Embedded in Cryptocrystalline Silica Varieties, Central Europe, Hungary

Variable cryptocrystalline silica varieties occur en masse in the fractures and cavities of the andesite host rock, showing different genetic and morphological features of variable microbial activity. Four types of CL features characterized silica phases. Raman spectroscopy supported variable amorphous carbon phases in inhomogenous distribution.