Stibnite Gem Guide and Properties Chart

Stibnite

By Tim Matthews, JD, FGA, GG, DGA,
CEO and President of JTV (retired)

Published: June 2014

Modified: November 2021

Stibnite forms as delicate, elongated crystals with metallic luster that are lead-gray in color. It is an important source of antimony. In ancient times it was ground into a powder and mixed with fat to be used as the eye makeup called kohl. It was also a component in ancient flash powder.

General Information

Classification
Optical Properties
Characteristic Physical Properties
Chemistry & Crystallography

Common Name

Stibnite

Species

Stibnite

Transparency

Opaque

Refractive Index

Over The Limit

Pleochroism

None

Hardness

2-2

Streak

Gray

Luster

Dull, Metallic

Stability

Poor

Fracture

Conchoidal, subconchoidal

Cleavage

Perfect, Imperfect

Chemical Name

Antimony Sulfide

Chemical Formula

Sb₂S₃

Crystal System

Orthorhombic

Chemistry Classification

Sulfide

Stibnite Colors

Black
Gray

Alternate Names

Antimonite

Countries of Origin

Romania; Unknown; China; Japan

Care

Soluble in hydrochloric and nitric acid. Do not expose to open flame as it melts at 546ºC. It is also very delicate so care must be taken not to damage specimens.