High-purity laboratory crucibles for high-temperature synthesis, calcination and ashing — alumina (corundum), magnesia, zirconia and yttria.
Start from your most demanding condition — temperature, chemical attack or budget — then narrow down.
Typical working-temperature and resistance values for the four high-purity ceramics. For the full table with melting points and applications, see our 4-material comparison.
| Material | Max Working Temp | Acid Resistance | Alkali Resistance | Thermal Shock | Relative Cost |
|---|---|---|---|---|---|
| Alumina (Al2O3) | ≈1750 °C | Good* | Fair | Good | Low |
| Zirconia (ZrO2) | ≈2200 °C | Excellent | Excellent | Moderate† | High |
| Yttria (Y2O3) | ≈2100 °C | Good | Excellent | Poor | Very High |
| Magnesia (MgO) | ≈2200 °C | Poor‡ | Excellent | Moderate | Low–Medium |
* Alumina resists most acids except HF and hot concentrated alkali. † Zirconia needs stabilization for thermal-shock use. ‡ Magnesia is attacked by acids and hydrates in water/steam.
Alumina (Al2O3) is the general-purpose, low-cost choice for routine firing and ashing up to about 1750°C. Zirconia (ZrO2) withstands the highest temperatures (about 2200°C) and resists acids and fluorides best. Magnesia (MgO) is the best against alkaline and reactive melts but hydrates in water. Yttria (Y2O3) is for ultra-high-purity alkaline, fluoride and rare-earth melts where the other three fail.
Typical continuous-use limits: alumina about 1750°C, zirconia about 2200°C, yttria about 2100°C, magnesia about 2200°C. Peak or short-term values are higher; always leave a safety margin below the melting point.
All four ceramics are stable in air and most inert atmospheres. In strongly reducing (for example H2, CO) or vacuum conditions, avoid magnesia and yttria as they can decompose or react; zirconia and alumina are more robust, but confirm your exact process with us.
Magnesia and yttria resist alkaline and many fluoride melts where alumina and zirconia are attacked. For strong hydrofluoric acid or molten fluorides, yttria is usually the safest choice. Tell us your exact medium and we will recommend the right material.
Yes. Beyond our 49 plus stock alumina sizes and standard zirconia, magnesia and yttria shapes, we make custom crucibles, boats, trays and lids to drawing or sample. Send your dimensions or a photo and we will quote.
Let them cool, brush off loose residue, and soak in dilute acid if needed (except magnesia, which must stay dry). Rinse with deionized water, dry thoroughly, and store in a desiccator. Avoid thermal shock — never quench a hot crucible in cold liquid.
Scuvette has manufactured high-purity laboratory ceramics and quartz optics since 2010. Crucibles are produced under an ISO 9001:2015 quality management system (Certificate NOA2408337) and are RoHS compliant (SGS report TAOEC26010238501). No minimum order quantity; custom sizes and OEM service are available.