Stibnite
Stibnite is a mineral. Its chemical formula is Sb2S3. It is the main ore of antimony. The American Museum of Natural History has a huge crystal of stibnite. Stibnite is soft, with a Mohs hardness of 2. Its specific gravity is 4.63.
Uses
[change | change source]Historical
[change | change source]Stibnite was used to make kohl, a type of eyeliner. Use of stibnite in cosmetics dates to Ancient Egypt.[source?]
Ore of antimony
[change | change source]Stibnite is the primary ore used to make elemental antimony. In most smelting processes, stibnite is heated with oxygen from the air to produce antimony trioxide and sulfur dioxide:[1]
- 2 Sb2S3 + 9 O2 → 2 Sb2O3 + 6 SO2
The antimony dioxide is then treated with a strong reducing agent like carbon monoxide to yield the purified antimony metal:
- Sb2O3 + 3 CO → 2 Sb + 3 CO2
Sources
[change | change source]- ↑ Moosavi-Khoonsari, Elmira; Mostaghel, Sina; Siegmund, Andreas; Cloutier, Jean-Pierre (2022). "A Review on Pyrometallurgical Extraction of Antimony from Primary Resources: Current Practices and Evolving Processes". Processes. 10 (8): 1590. doi:10.3390/pr10081590.