As Lapis Lazuli (Arabic and Latin-blue stone) is composed of several minerals-in addition to lazurite (25-40 percent), including augite,...

Amazonite also called Amazon stone (it derived from the Amazon) is a mostly opaque, green green sodium feldspar. Color distribution is...

Amethyst is the most valued stone in the Quartz group. The name means "not drunken" (Greek), as Amethyst was worn as an amulet against...

AMBER: A NATURAL TIME CAPSULE