Hornblende Gneiss thin section slide exhibiting an abundance of the mafic mineral hornblende, accompanied by less abundant biotite mica, quartz and feldspar. Hornblende is the bulk constituent of the rock and it is arranged in concentrated mafic bands along with biotite mica. Light bands separate the dark horizons and they are comprised almost entirely of quartz. In thin section view however, at such a small scale, it is harder to discern the banding. The alternating light and dark bands, known as ' gneissic banding ' can be seen much more clearly in hand specimen. Both thin section and hand specimen supplement each other to allow for a more detailed rock description and interpretation to be delivered. This material was collected by staff from Southern 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.