Description
GRAPHIC PEGMATITE SPHERE
This is the graphic pegmatite sphere with occasional inclusions of schorl. Diameter 3.2″ (81mm). Weight – 25.2oz (715 grams). Origin: Russia, Transbaikalia.
Some information about pegmatite:
A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than 1 cm (0.4 in) and sometimes greater than 1 meter (3 ft). Most pegmatites composed of quartz, feldspar, and mica, having a similar silicic composition to granite. However, rarer intermediate composition and mafic pegmatites are known.
Many of the world’s largest crystals found within pegmatites. These include crystals of microcline, quartz, mica, spodumene, beryl and tourmaline. Some individual crystals are over 10 m (33 ft) long.
The word pegmatite derives from Homeric Greek pegnymi, which means “to bind together”, in reference to the intertwined crystals of quartz and feldspar in the texture known as graphic granite.
