Description
FELDSPAR SPHERE
This is the feldspar sphere with iridescence in silvery colors (moonstone). Diameter 4.3″ (110mm). Weight – 3.9lb (1760 grams). Origin: Russia, Siberia.
Some information about feldspar:
Feldspars are a group of rock-forming tectosilicate minerals that make up as much as 60% of the Earth’s crust.
Feldspars crystallize from magma as veins in both intrusive and extrusive igneous rocks and are also present in many types of metamorphic rock. Rock formed almost entirely of calcic plagioclase feldspar known as anorthosite. Feldspars also found in many types of sedimentary rocks.
The name feldspar derives from the German Feldspat, a compound of the words Feld, “field”, and Spat, “a rock that does not contain ore”. The change from Spat to -spar influenced by the English word “spar”, a synonym for “mineral”. Feldspathic refers to materials that contain feldspar. The alternate spelling, felspar, has largely fallen out of use.