Amethyst

The ancient Greeks believed that amethyst  would prevent you from becoming intoxicated.  They would wear amethyst around their neck when drinking wine to prevent drunkenness.

Amethyst has a hardness of 7 and can be used in any jewelry application.  This quartz stone is purple due to trace element of iron and aluminum.  Often called the gemstone of love, the amethyst is probably the most popular gemstone in the world.