Lead-Zinc Concentrate

Lead-Zinc Concentrate from Pakistan

Lead-zinc concentrate is a bulk flotation product containing both lead sulphide (galena) and zinc sulphide (sphalerite) minerals in a single concentrate. It is produced from polymetallic ores where lead and zinc mineralization are finely intergrown or where separate lead and zinc flotation circuits are not economically justified. The concentrate is a fine, dense, dark grey to silver-black powder with high combined Pb+Zn content and recoverable silver credits. Pakistan’s lead-zinc deposits across Balochistan and Khyber Pakhtunkhwa yield complex polymetallic ores that are processed into bulk concentrate at flotation plants near the mining areas.

Available Forms

• Flotation bulk concentrate: fine powder, 80% passing 75 microns

• Filtered cake: 8-12% moisture

• Dried concentrate: < 5% moisture

• Custom moisture and sizing on request

Industrial Uses

• Imperial Smelting Furnace (ISF): Bulk lead-zinc concentrate is the standard feedstock for ISF smelters, which simultaneously produce lead bullion and zinc metal from a single mixed feed. The ISF process is specifically designed to treat bulk Pb-Zn concentrates that cannot be economically separated

• Lead smelting with zinc recovery: Some lead smelters accept Pb-Zn bulk concentrate and recover zinc as a secondary product from slag fuming or Waelz kiln processing

• Zinc smelting with lead recovery: Zinc smelters equipped to handle lead-bearing concentrates process the material and recover lead as a byproduct through lead residue treatment

• Hydrometallurgical processing: Newer hydrometallurgical routes (pressure leaching, atmospheric leaching) can treat bulk Pb-Zn concentrates to selectively dissolve and recover both metals

• Silver recovery: Silver present in both the galena and sphalerite fractions is recovered during smelting and refining. Silver credits can be a significant revenue component, especially from argentiferous deposits

• Sulphuric acid co-production: SO₂ gas from roasting or smelting the concentrate is captured and converted to sulphuric acid as a co-product

• Custom toll processing: Bulk concentrate is sold to custom smelters and toll processors under TC/RC contracts for multi-metal recovery

Quality Assurance

Each lot includes a Certificate of Analysis reporting Pb, Zn, Ag, Au, Fe, S, SiO₂, Cu, Cd, As, Sb, Bi, Hg, Se, Cl, F, moisture, and particle size distribution. Combined Pb+Zn payable content is the primary value determinant. Assays are performed by internationally accredited laboratories (ISO 17025). Settlement assays follow standard umpire procedures. Pre-shipment samples are provided for buyer approval. Third-party inspection (SGS, Intertek, Alfred H. Knight, Alex Stewart, or equivalent) can be arranged for sampling, weighing, and moisture determination.