Corundum var. Sapphire
Sapphire (name from Hebrew). While corundum consists of pure Al2o3, sapphires always contain an admixture of other elements (iron, chromium, copper, magnesium, etc.) that give it a blue, red, yellow, pink, purple, orange or greenish color.
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Sapphire (name from Hebrew). While corundum consists of pure Al2o3, sapphires always contain an admixture of other elements (iron, chromium, copper, magnesium, etc.) that give it a blue, red, yellow, pink, purple, orange or greenish color.