Corundum

Crystal system · Trigonal

Corundum is an oxide mineral prized by collectors for its exceptional color range, with known Chinese sources.

About Corundum

Corundum belongs to the oxide class in the corundum group and has the chemical formula Al2O3. It crystallizes in the trigonal system and is one of the most visually varied minerals in the collector market.

Identification & care

Specimens usually show bipyramidal, tabular, barrel-shaped prisms; massive (emery). Its color range is broad, including colorless, gray, blue (sapphire), red (ruby), pink, yellow, orange, green, and purple. The luster is adamantine to vitreous, the streak is white, and specimens range from transparent to opaque. The cleavage is none (parting on {0001} and {1011}). The fracture is conchoidal, which aids identification.

Collector context

Collector notes

Among collectors of crystallized species, Corundum is a recognized reference. Corundum is widely represented across Chinese provinces, including Fujian, Anhui, Hebei, Guangxi.