Galena (PbS) is the principal lead ore mineral. It commonly occurs with sphalerite, pyrite, carbonates or siliceous gangue, so the grinding target depends on mineral association rather than lead content alone.
- Principal mineral
- Galena (PbS)
- Common association
- Sphalerite and other sulfides
- Critical objective
- Selective liberation
Why is galena central to lead ore?
Galena is a dense lead sulfide and one of the main economic phases in many lead deposits. Real ore, however, also contains sphalerite, pyrite and gangue minerals that alter the flowsheet.
The grain size of lead minerals and the way they are locked with other sulfides determine how much grinding is needed after crushing.
Why does selective liberation matter?
In ores containing both lead and zinc minerals, simply grinding finer does not always improve separation. Excess fines can increase surface area and classification duty.
The grinding circuit should be tested to expose galena sufficiently while limiting unnecessary overgrinding of sphalerite and gangue.
Lead-dominant ore versus a polymetallic Pb-Zn system
In lead-dominant ore, galena liberation and the behaviour of lead value are central. In a polymetallic Pb-Zn system, galena and sphalerite must be prepared together for selective downstream separation.
In both cases the grinding target is validated against mineral association and downstream separation testwork.
Evaluation inputs
- Galena, sphalerite and pyrite proportions
- Mineral locking and liberation size
- Feed PSD and moisture
- Target grinding product and downstream separation route
- Representative testwork and mass-balance data