Stibnite is Sb₂S₃ and the predominant ore mineral of antimony. It can form bladed or massive aggregates and is commonly associated with quartz, pyrite or other sulfides.
- Formula / structure
- Sb₂S₃
- Ore role
- Predominant antimony ore mineral
- Preparation focus
- Controlled liberation of a brittle sulfide from gangue
What is Stibnite and how does it occur in ore?
Stibnite occurs with gold in some Au-Sb deposits. The actual host of gold—stibnite, pyrite/arsenopyrite or free gold—varies by ore and must be determined mineralogically.
Why does stibnite require care during comminution?
Stibnite is a relatively soft, brittle sulfide. If it breaks into fine fractions faster than quartz gangue, overgrinding can make selective separation more difficult.
Which behaviour matters during ore preparation?
Grinding should be limited to the liberation required, while size-by-size antimony distribution is used to identify fine-particle losses.
If arsenic or other sulfides are present, concentrate quality is not defined by Sb grade alone. Penalty and impurity elements should be included in the product specification.
Which inputs should be verified?
- Stibnite grain size
- Association with Au and other sulfides
- Liberation size
- Antimony distribution by size fraction
- Arsenic and other penalty elements