Quartz Glass

Specialglass supplies quartz glass (fused silica, SiO₂) for the applications where ordinary optical glass gives out — under extreme heat, aggressive chemistry, or demanding UV-to-IR optics. With purity above 99.99% SiO₂, continuous service to ~1000 °C, and one of the lowest thermal expansion coefficients of any glass (~5.5 × 10⁻⁷/°C), quartz glass holds its shape and clarity through thermal shock that would crack borosilicate. We supply it as plates, tubes, cylinders, and rings — cut, ground, and polished to your drawing.

Quartz glass earns its place in high-tech industry, research, and development on three properties working together. Its near-zero thermal expansion makes it almost indifferent to temperature swings — it withstands continuous service to ~1000 °C and survives rapid heating and quenching. It resists nearly every chemical, yielding only to hydrofluoric acid and hot concentrated phosphoric acid. And it transmits light cleanly from the deep UV through the near IR, which is why it does double duty as both a structural and an optical material in the same demanding environments.

Two production routes give quartz glass its grades, and the route determines both purity and optical reach:

• Natural (fused) quartz glass. Melted from finely ground rock crystal in a hydrogen-oxygen flame. Valued for its strong UV transmission and lower cost, it suits high-temperature and general optical use where trace inclusions are acceptable.
• Synthetic fused silica. Produced from high-purity silicon tetrachloride (SiCl₄) by flame pyrolysis. This route delivers the highest purity, minimal inclusions, and the most constant optical properties — the choice for precision work across the UV, visible, and IR.

These map onto the standard optical grades: synthetic material covers the deep-UV JGS1 (185–2500 nm) and UV JGS2 (220–2500 nm) bands, while low-hydroxyl JGS3 (260–3500 nm) serves the infrared, suppressing the ~1400 nm water-absorption band for clean IR transmission.

Thermal, density, and expansion figures are intrinsic to fused silica and apply across all grades; transmittance bands are grade-specific.

We supply quartz glass in the geometry your application needs, finished from customer drawings:

• Plates — round, square, or tongue-shaped (oval)
• Tubes, cylinders, and rings — in a range of sizes and tolerances
• Cutting, grinding & lapping — dimensional and flatness control
• Precision polishing — surface quality to optical scratch-dig grades
• Bevelling, drilling, and edge work to spec
• Customer-supplied material accepted alongside our own stock