Amethyst

The violet, purple to almost too pink variety of quartz is called Amethyst. It was believed that amethyst used to guard against drunkenness. Its name is derived from a Greek word Amethystos meaning not intoxicated.

Hardness :7

Appearance:
Amethyst shades from purple, lilac or mauve color. It is basically associated to the color purple. There is a distribution of the color in striking patches and bands. Amethysts are given both cut and cabochon. Amethyst generally has a good luster.  To improve the color amethyst is generally heated.

Occurrence:
The finest amethysts are from Brazil. Amethyst is also found in Zambia, India, Madagascar, Australia and Uruguay. 

Value:
Though amethyst is one of the most highly priced quartz, but still it is not expensive and is easily available. But a few centuries ago it was very highly priced.