Quartz, which comes in the shades of purple, lilac or mauve, is known as amethyst, which is considered as the most highly valued stone in the quartz group. Amethyst is dichroic due to which it shows a bluish or reddish purple hue when it is seen from different sides. Amethyst has characteristics inclusions, which look like tiger-stripes, thumbprints or feathers. Some amethysts are made to turn to yellow color by heat treating it, which turns it into citrine. Quartz which is partially amethyst and partially citrine is known as ametrine. Amethyst is largely found in Brazil. Amethyst from Canada is more violet than the ones found in other localities whereas, amethyst from the Urals (Russia) has a more red tone than the others. Other localities are Sri Lanka, India, Madagascar, Uruguay, the USA, Australia, Germany, Zambia and Namibia.

Crystal Structure: Trigonal

Hardness: 7

Specific Gravity: 2.65

Refractive Index: 1.54-1.55

Colors: Violet and different shades of violet (with reddish or bluish tones).

Luster: Vitreous