Berthierite
Mineral FeSb2S4
Take care.
- Toxic: Wash your hands after handling it, don't lick or taste it, and don't make dust.
About it
Dark grey fibrous or bladed iron-antimony sulfide with an iridescent tarnish, easily taken for stibnite but with a browner tint. Named for Pierre Berthier; found with stibnite in antimony veins.
- Type
- Mineral
- Group
- Sulfide
- Formula
- FeSb2S4
- Hardness (Mohs)
- 2–3
- Specific gravity
- 4.6–4.7
- Streak
- dark brownish grey
- Lustre
- metallic
- Crystal system
- Orthorhombic
- Colours
- dark steel grey, iridescent tarnish
- Transparency
- opaque
- Cleavage and fracture
- indistinct lengthwise
Typical values: real specimens vary. For more, see mindat.org.