Q2: What is the difference between fused silica and fused quartz?
- Share
- Issue Time
- Jun 8,2026

Q2: What is the difference between fused silica and fused quartz?
A: These two names are frequently used interchangeably in the industry, but they are distinguished by raw materials, production technology, internal composition and practical performance, and are suitable for completely different application scenarios.
| Aspect | Fused Silica (Synthetic) | Fused Quartz (Natural) |
|---|---|---|
| Raw Material | Made from synthetic silicon compounds through flame hydrolysis or CVD technology | Processed from natural high-purity quartz crystals and silica sand |
| Purity Level | Ultra-high purity, metallic impurities are controlled at ppb level | High purity, impurities stay at ppm level, slightly lower than synthetic type |
| OH Content | 1000–2000 ppm | Less than 5–30 ppm after vacuum or electric melting |
| Optical Feature | Excellent deep ultraviolet transmission, the cut-off wavelength is about 170 nm | Better infrared transmission performance, relatively weak in deep ultraviolet band |
| Main Usage | Semiconductor lithography equipment, deep UV laser optical components | Infrared optical systems, long-term high-temperature industrial structural parts |
In actual procurement and design, engineers will select materials strictly according to the spectral requirements and working environment of the equipment to avoid performance mismatch.