Corundum is a crystalline form of aluminium oxide (Al2O3) typically containing traces of iron, titanium, vanadium, and chromium. [3][4] It is a rock -forming mineral.

What is Corundum? Corundum is a rock-forming mineral that is found in igneous, metamorphic, and sedimentary rocks. It is an aluminum oxide with a chemical composition of Al 2 O 3 and a member of …

Jul 1, 2024 · Corundum is a mineral that is primarily composed of aluminum oxide (Al2O3) and is one of the naturally occurring crystalline forms of aluminum oxide. It is a very hard mineral and is commonly …

Corundum, naturally occurring aluminum oxide mineral (Al2O3) that is, after diamond, the hardest known natural substance. Its finer varieties are the gemstones sapphire and ruby (qq.v.), and its …

Corundum is used as an abrasive ("Emery"), and the gem varieties of corundum are better-known as Ruby and Sapphire.

Detailed description, properties, and locality information guide about the mineral corundum: ruby and sapphire.

Jul 2, 2025 · Corundum is a crystalline form of aluminum oxide (Al₂O₃) and one of the hardest naturally occurring minerals, second only to diamond on the Mohs hardness scale.

Oct 21, 2024 · Due to natural corundum's popularity and high value, synthetically produced gem corundum has been used as an inexpensive substitute for many years. Corundum is also used as an …

Mar 3, 2026 · Corundum is a crystalline form of aluminum oxide (Al2O3) and ranks as the second hardest mineral on Earth, trailing only diamond with a remarkable Mohs hardness rating of 9. This …

Corundum is a relatively common mineral that once found wide application as an industrial abrasive. Gem corundum is mined almost exclusively from gem gravel deposits.