Glittering blue sapphires, so suggestive of piercing cold, have remarkably hot origins deep beneath the surface. For years, sapphires been turned up in volcanic deposits such as the Volcanic Eifel, ...
Corundum is also responsible for another birthstone: July's ruby. Sapphires come in an array of colors, including orange, yellow, green, pink and purple. However, they're best known for their blue ...