Ruby

Variety of corundum; mineral; gemstone

Ruby is a pinkish-red to blood-red-colored gemstone, a variety of the mineral corundum, consisting of aluminium oxide (α-Al2O3). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires, and rubies are also sometimes referred to as "red sapphires".

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