Amethyst is a variety of quartz with purple coloration which is caused by impurities of iron or manganese.

Color: Amethyst occurs in a wide range of purple shades. Index of refraction: 1.544-1.553 Birefringence: 0.009. The purple color can be throughout or can be in bands with white quartz.

Its color and beauty are without rival, even from other much more expensive purple gems. Purple is the color of royalty. The rich and powerful have worn it as a mark of rank for hundreds of years. Even today as an affordable gem available in a wide selection of cut stones it has a regal air.

Amethyst is found in many areas around the world, including Mexico, Brazil, Uruguay, Africa, and Russia. In the United States, Amethyst can be found in Montana, Arizona, Colorado, Maine, and New Jersey.

In Canada, Amethyst is found near Thunder Bay and in Nova Scotia. One typical feature of Amethyst from Thunder Bay is its reddish coloration, caused by an internal coating of red hematite (iron).

Russian stones ( form the Urals) are very clear and dark. They are cut for fine expensive gemstones and gave rise to the term Siberian to indicate the very best Amethyst. Uruguayan and Bahain represent high medium and low grades, regardless of the source.

Amethyst crystals are hexagonal and can occur as tall prismatic crystals or short stubby ones (Crystal system: trigonal). The crystals often have horizontal striations on their sides or faces. Hardness: 7 Cleavage: none

Amethyst is often cut as brilliant round and/or oval stones to maximize the color. Other cuts are used when the crystal shape would not yield a fine oval or round.

Amethyst is one of several gem quartz varieties. The others are :

• Citrine. A yellow to orange variety, rare in nature but often created by heating Amethyst.
• Rock crystal, a clear stone, occasionaly used as a gem.
• Rose quartz, a pink stone, sometimes cut as a cabochon.
• Smoky quartz, the brown to gray quartz stones, sometimes in error called smoky topaz.

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