Schorl

Cyclosilicate

Tourmaline ( /ˈtʊərməlɪn/ TOOR-mə-lin , -⁠leen boron compounded with elements such as aluminium , sodium. Tourmaline is classified as a semi-precious stone. This gemstone can be found in a wide variety of colors.

Identification

Color of mineral

Black

Brown

Red

Orange

Yellow

Green

Blue

Violet

Pink

Mohs scale ( mineral hardness )

Density ( specific gravity )

1.635

1.61

Luster ( interacts light )

Vitreous

Resinous

Crystal ( diaphaneity )

Trigonal