Corundum
/kəˈrʌn.dəm/noun
A very hard mineral, aluminum oxide, that includes ruby and sapphire as varieties when colored by impurities.
Did you know?Corundum is the mineral species that includes both ruby and sapphire, and its name entered English through a chain of borrowing from South Asian languages rather than from a classical “gem” word.
Etymological Timeline
Ancient India
Sanskrit
kuruvinda
“A hard stone or gemstone, likely a type of ruby or corundum-like mineral.”
Medieval India
Prakrit/Dravidian
korund
“A local term for a hard abrasive stone used in trade and lapidary work.”
17th Century
Portuguese
corindon
“A borrowed term for a hard mineral, taken into European mineralogical writing through contact with Asia.”
18th Century
French
corindon
“A mineralogical term for the hard oxide mineral used as an abrasive and gemstone host.”
18th Century
English
corundum
“The English mineral name for the extremely hard aluminum oxide mineral.”
Explore more surprising origins