Photo: David Hospital · CC BY-SA 4.0

Tourmaline mineral

Properties

Chemical formula

CaFe²⁺₃ Al₆(Si₆O₁₈)(BO₃)₃(OH)₃O

Group

Oxides

Crystal system

Trigonal

Hardness (Mohs)

—

Color

Black

Luster

—

Streak

Grey

Density

—

Cleavage

—

Fracture

—

Tenacity

—

Crystal habit

—

Transparency

—

Space group

R3m

Fluorescence

—

Magnetism

—

Radioactivity

—

Refractive index

—

Optical character

—

Birefringence

—

Pleochroism

—

Strunz classification

—

Dana classification

—

IMA status

Approved mineral and/or valid name (A)

IMA symbol

Lcc

Locality

🇱🇰 Ratnapura

Type locality

—

Discovery year

—

Source: Wikidata