Mineral Name

Tourmaline

Chemical Formula

(Na,Ca)(Li,Mg,Al)3-(Al,Fe,Mn)6(BO3)3(Si6O18)(OH)4

Creator

Preview

Color

commonly black, but ranges from brown, violet, green, pink, green

Class

Article

Luster

vitreous

Diaphaneity

transparent to translucent

Hardness

7-7.5

Cleavage

indistinct

Fracture

uneven, conchoidal, brittle

Density

2.82-3.32

Crystal Shape

elongated, acicular prisms, sometimes radiating. Prominent trigonal shape to prisms. Vertically striated.

Crystal System

Hexagonal

Streaming Media