Better known from its colored varieties, ruby and sapphire, corundum is a highly appealing mineral for both decorative and industrial use. The bright, deep colors along with its rarity and high hardness has made it an excellent...

Cinnabar has been mined for thousands of years as it is the main ore of mercury. Its name is derived from the Arabic word “Zinjafr,” meaning dragon's blood, appropriate given the mineral’s blood red color. Cinnabar historically has been ...