This product, the Magnesium Oxide Ark from Canrd, is developed for high-temperature experimental and sintering applications requiring a stable, refractory container. Manufactured from high-purity fused magnesium oxide (over 99.3% purity, white in appearance), it offers excellent thermal stability, with a recommended working temperature up to 1900 °C in oxidizing atmospheres and up to 2000 °C under nitrogen or vacuum, peaking at 2200 °C. Available in multiple sizes (10 ml to 70 ml, with or without covers), it is suited for melting or calcining materials that do not contain silica, as magnesium oxide reacts with silicon dioxide at high temperatures to form magnesium silicate. Users should note that the lid is plate-shaped and does not provide a tight seal, and a heating rate of ≤ 8 °C/min is advised to avoid thermal shock. This product is commonly used in research laboratories for high-temperature material synthesis, ceramic processing, and metal alloy preparation where a pure oxide crucible is needed.