Samples of the permineralized tree fern Psaronius sp. from the Lower Permian Rotliegend of Chemnitz were examined to find out their chemical composition and structural behavior. The inhomogenic distribution of elementary constituents of oxides, sulfates and carbonates within the silica-matrix consisting of alpha -quartz and chalcedony were formerly detected by analytical X-ray microscopy. Most of the compounds could be revealed by Raman spectroscopy. Calcite and barite developed in small fissures. Iron of different oxidation level is the prevailing pigment in the agate preserved adventitious roots. Coalified cellulose whose structure mainly corresponds to anthracite reflects the anatomical detail of the former organic tissues.