Celestite Lumps

Celestite Lumps from Pakistan

Celestite is a strontium sulphate mineral (SrSO₄) containing up to 56.4% strontium oxide (SrO) in its pure form. It is the world’s only commercially significant source of strontium. The mineral occurs in sedimentary formations, often associated with evaporite deposits, gypsum, and limestone. Pakistani celestite has a characteristic pale blue-grey to white crystalline appearance with a glassy to pearly lustre. Deposits in Balochistan and Sindh produce celestite ore with SrSO₄ content ranging from 80% to 96%, suitable for direct processing into strontium carbonate and other strontium compounds.

Specifications

• Mineral: Celestite (SrSO₄)

• SrSO₄ Content: 80-96% (grade-dependent)

• SrO: 45-53%

• BaSO₄: 0.5-5%

• CaSO₄: 0.5-4%

• SiO₂: 0.5-3%

• Fe₂O₃: < 0.5%

• Moisture: < 2%

• Hardness (Mohs): 3-3.5

• Specific Gravity: 3.9-4.0

• Colour: Pale blue-grey to white

Available Forms

• Run-of-mine (ROM) lumps: 10-250 mm

• Crushed lumps: 10-80 mm, 10-50 mm

• Screened sizes: 0-10 mm, 10-30 mm, 30-80 mm

• Hand-sorted lumps: 90-96% SrSO₄

• Custom sizing available

Industrial Uses

• Strontium carbonate (SrCO₃) production: Celestite is converted to strontium carbonate through the black ash process (reduction with coke/coal) or direct carbonation. SrCO₃ is the primary commercial strontium compound and the starting material for most downstream strontium products

• CRT and LCD glass: Strontium carbonate from celestite is a key ingredient in cathode ray tube (CRT) glass faceplate formulations, providing X-ray absorption. It is also used in LCD substrate glass and specialty flat glass

• Ferrite magnets: Strontium ferrite (SrFe₁₂O₁₉) permanent magnets produced from strontium carbonate are used in motors, speakers, magnetic separators, and automotive sensors. Ferrite magnets are the largest volume permanent magnet type globally

• Pyrotechnics and fireworks: Strontium compounds from celestite produce the characteristic brilliant red colour in fireworks, signal flares, military tracer rounds, and pyrotechnic compositions

• Specialty ceramics: Strontium compounds are used in ceramic capacitors, piezoelectric ceramics (strontium titanate), and electronic ceramics for telecommunications and electronics

• Zinc refining: Strontium carbonate is used in zinc electrolysis to remove lead from the electrolyte, improving zinc cathode purity

• Sugar refining: Strontium hydroxide from celestite is used in the beet sugar refining process to improve sugar extraction yield

• Drilling fluids: Ground celestite is used as a weighting agent in oil and gas drilling muds as an alternative to barite

• Pigments: Strontium chromate from celestite is used as a corrosion-inhibiting pigment in aerospace primers and marine coatings

Quality Assurance

Each lot includes a Certificate of Analysis reporting SrSO₄, SrO, BaSO₄, CaSO₄, SiO₂, Fe₂O₃, moisture, and size distribution. Pre-shipment samples are provided for buyer approval. Third-party inspection (SGS, Intertek, or equivalent) can be arranged on request.