Biotite 8mm Round Orange - 15-16 Inch garnet Dumortierite is an aluminum borosilicate

Dumortierite is an aluminum borosilicate mineral that varies in color from blue

This item is treated and dyed agate

but has been used historically to describe the transparent variety

plant materials

and turquoise is a leftover mineral from these practices

Biotite 8mm Round Orange - 15-16 Inch garnet Dumortierite is an aluminum borosilicateBiotite is a name used for a large group of black mica minerals that are commonly found in igneous and metamorphic rocks. These include annite, phlogopite, siderophyllite, fluorophlogopite, fluorannite, eastonite, and many others. The name "biotite" is used because these minerals generally cannot be distinguished without optical, chemical, or x ray analysis. Biotite was named in honor of the French physicist Jean Baptiste Biot, who performed early