Hitech 99.9% Bowl Shape Alumina Crucible (Standard Sizes) & Trays are Pure White in colour and made with 99.9% purity. Hitech 99.9% Bowl Shape Alumina Crucible (Standard Sizes) can be used up to 1800oC as maximum temperature. As 99.9% Bowl Shape Alumina Crucible (Standard Sizes) are well Polished and Pure, they won't react with other materials.