Biotite Granite (1kg)
Coarse grained variation of granite, composed of quartz, feldspar and biotite. These samples were collected from Scotland and are ideal for educational use.
A coarse grained, felsic intrusive rock. The minerals which make up a granite are typically quartz, feldspars and micas. In the case of biotite granite, the constituent minerals are milky (white) quartz, plagioclase feldspar and biotite mica crystals. The biotite appears as small black 'flecks' on the surface of the specimens. These particular samples come from Scotland, UK. Specimens are supplied in a polythene bag in lots of 1 kg with a label.