Antimony Concentrate

Antimony Concentrate from Pakistan

Antimony concentrate is produced by beneficiating stibnite (Sb₂S₃) ore through gravity and flotation circuits. The process exploits the high specific gravity (4.6) and hydrophobic surface properties of stibnite to separate it from lighter gangue minerals, producing a fine, dense, silver-grey powder with 55-65% Sb content. Antimony concentrate is the standard smelter feedstock for producing antimony metal, antimony trioxide (ATO), and other antimony compounds. Pakistan’s stibnite deposits are processed at beneficiation plants near the mining areas in Balochistan and Khyber Pakhtunkhwa.

Available Forms

• Gravity concentrate: 55-62% Sb (coarser grind, lower cost)

• Flotation concentrate: 60-65% Sb (finer grind, higher grade)

• Dried powder: < 3% moisture

• Filtered cake: 8-12% moisture

• Custom moisture levels on request

Industrial Uses

• Antimony trioxide (ATO) production: Concentrate is volatilized or roasted to produce Sb₂O₃, the primary synergist in halogenated flame retardant systems. ATO is added to plastics, textiles, rubber, electronics, cables, and building materials to meet fire safety standards. This is the single largest end-use of antimony globally

• Antimony metal production: Concentrate is reduced to antimony metal (99.65-99.90% Sb) by iron precipitation smelting, blast furnace reduction, or electrolysis. Metal is used in semiconductor compounds, thermoelectric devices, and specialty alloys

• Lead-acid battery alloys: Antimony from concentrate is alloyed with lead for battery grid production. Pb-Sb alloys improve grid strength and electrochemical cycling performance in automotive and industrial batteries

• Lead hardening alloys: Antimony is added to lead for type metal, Babbitt bearing metal, cable sheathing, ammunition, and other applications requiring harder, stronger lead

• Flame retardant chemicals: Beyond ATO, concentrate is processed into sodium antimonate (glass and ceramics), antimony pentoxide (intumescent coatings), and other specialty flame retardant compounds

• PET catalyst: Antimony trioxide derived from concentrate is used as a polycondensation catalyst in polyester (PET) manufacturing for bottles, films, and fibers

• Defense and munitions: Antimony compounds from concentrate are used in explosive primers, tracer ammunition, infrared optics, and night vision devices

• Glass decolorizing and opacifying: Antimony compounds are used as fining agents and opacifiers in glass and enamel production

Quality Assurance

Each lot includes a Certificate of Analysis reporting Sb, As, Pb, Fe, S, SiO₂, Cu, Bi, Hg, Se, moisture, and particle size distribution. Assays are performed by accredited laboratories (ISO 17025). Pre-shipment samples are provided for buyer approval. Third-party inspection (SGS, Intertek, Alex Stewart, or equivalent) can be arranged. Umpire assay provisions are available for large contracts.