Gneiss Slide

Norwegian gneiss thin section slide exhibiting a dominant felsic composition i.e. quartz and plagioclase with less prominent mafic bands.The dark mafic minerals are typically biotite mica and pyroxene however in thin section view, at such a small scale, it is harder to discern these concentrated mafic accumulations as bands. In hand specimen the alternating light and dark bands, known as ‘ gneissic banding ‘ are much more clear. The alternative views of hand specimen and thin section supplement each other to allow for the most detailed rock descriptions and interpretations to be delivered. Due to the fact that this gneiss contains more feldspar and quartz and less of the dark mafic minerals, it is sometimes known as migmatitic gneiss. We collected this material from Evje, Norway. Each section is made to 30 microns thickness and the glass is 46 x 27 mm in size with a cover slip. Supplied in a protective card sleeve with a label, ideal for microscopy and educational purposes.