- A crystalline form of aluminum oxide that is a mineral and a valuable gemstone.
- A naturally occurring mineral that is a form of aluminum oxide and can be found in various colors including red (ruby), blue (sapphire), and colorless (white sapphire).
From the tamil word 'kurundam' meaning 'ruby'.
- The corundum was valued for its beauty and rarity.
- The corundum was used in jewelry and other decorative objects.
- The red corundum is known as a ruby.
- The blue corundum is known as a sapphire.
- The colorless corundum is known as a white sapphire.