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Corundum

co·​run·​dum | kə-ˈrən-dəm

noun

A very hard mineral that consists of Aluminum Oxide occurring in massive and crystalline forms and often containing trace amounts of Iron, Titanium, Vanadium and Chromium

The name corundum is derived from the Tamil-Dravidian word kurundam, meaning "ruby-sapphire". Corundum is a rock-forming mineral, containing small traces of titanium, iron, chromium, and vanadium. The mineral corundum is renowned for being extremely hard, and for providing gorgeous, translucent crystals, ranging in a myriad of hues. What’s more, corundum is dubbed the 3rd hardest mineral, where the diamond takes the 1st place and moissanite takes the 2nd place. Furthermore, the mineral corundum is deemed a hardness of 9 on the well-known Mohs Hardness Scale. This extreme hardness makes the mineral the best choice for an abrasive, beautiful crystal. Due to corundum’s hardness, toughness, and chemical stability, organic corundum is used in a multifariousness of industrial uses. What’s more, corundum may be used to make industrial bearings, wafers for circuit boards, scratch-resistant windows for electronic instruments, to name a few. Lastly, it’s important to know the specifications of corundum’s colors. A corundum with a red hue is called "ruby, where a corundum with a blue hue is "sapphire”. Colorless corundum is deemed "white sapphire”, and corundum of any other color those listed above is considered "fancy sapphire”.

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