CORUNDUM CRYSTALS SPECIMENS

Corundum is a mineral composed of aluminum oxide, renowned for its hardness and its gem varieties, sapphire and ruby. Pure corundum crystals are typically colorless, but trace elements give rise to vibrant colors. For instance, chromium impurities create red rubies, while iron and titanium impart blue hues to sapphires. Corundum crystals can also display a range of other colors, including pink, yellow, green, and purple, depending on the specific impurities present.

Corundum commonly forms in prismatic, hexagonal crystals with a glassy to sub-metallic luster and can exhibit perfect transparency or be opaque. Its hardness ranks at 9 on the Mohs scale, making it one of the hardest minerals, second only to diamond.