Strontium Sulfate

Updated: 2026-08-06

Overview

Strontium sulfate (SrSO₄) is a naturally occurring mineral known as celestine, though it is also synthesized for industrial use. It is valued for its high thermal stability and low solubility in water, making it suitable for high-temperature applications. The compound is non-toxic and environmentally benign, which expands its usability across multiple industries. In nature, strontium sulfate is found in sedimentary rocks and is often mined as a source of strontium. Synthetically produced strontium sulfate is preferred for industrial applications due to its consistent purity and particle size, which are critical for manufacturing processes.

Physical and Chemical Properties

Strontium sulfate is a white crystalline powder with a density of 3.96 g/cm³ and a melting point of 1,606°C. It decomposes at high temperatures rather than boiling, which makes it useful in applications requiring thermal resistance. The compound is slightly soluble in water (0.0135 g/100 mL at 25°C) and insoluble in ethanol, contributing to its stability in aqueous environments. Its chemical inertness and non-reactive nature make it a preferred additive in materials exposed to harsh conditions. The high refractive index of strontium sulfate also lends itself to optical applications, though this is less common compared to its use in ceramics and pyrotechnics.

Main Applications

Strontium sulfate is primarily used in the ceramics industry to enhance the opacity and durability of glazes. It acts as a flux, lowering the melting point of ceramic mixtures while improving their mechanical strength. In pyrotechnics, it serves as a red colorant in flares and fireworks due to the bright crimson emission of strontium ions when heated. The glass industry utilizes strontium sulfate to reduce glare and improve the clarity of optical glass. Additionally, it is employed in pigments and coatings for its UV-reflective properties. Lesser-known applications include its use in drilling fluids for the oil and gas industry, where it functions as a weighting agent.

Safety and Storage

Strontium sulfate is considered low-risk, with no significant toxicity reported for humans or the environment. However, prolonged exposure to dust may cause mild respiratory irritation, so proper ventilation and personal protective equipment (PPE) like masks are recommended during handling. Storage should be in a cool, dry place, away from strong acids or bases that could react with the compound. Bulk quantities are typically packaged in moisture-resistant bags or containers to prevent clumping. Shelf life is indefinite if stored correctly, though buyers should inspect for moisture absorption over time.

B2B Procurement Guide

When procuring strontium sulfate, prioritize suppliers that provide certificates of analysis (CoA) to verify purity, which typically ranges from 98% to 99.5% for industrial-grade material. Particle size distribution is another critical factor, especially for ceramic and pigment applications, where consistency affects performance. Pricing fluctuates based on purity and order volume, with bulk purchases often discounted. Request samples to test compatibility with your processes before large-scale orders. Logistics considerations include packaging (25kg bags or bulk pallets) and lead times, particularly for international shipments where customs delays may occur.