Topaz is a form of aluminum silicate with fluorine. Chemically, the composition of topaz can be represented by the formula Al2SiO4(F,OH)2. Topaz crystals are generally prismatic, and terminate in pyramidal or other faces. Topaz crystals often have well-developed basal cleavage. Cutting and polishing the crystals as gemstones requires particular care. Topaz typically crystallizes in granitic pegmatities, and in vapor cavities of rhyolitic lava flows. Topaz is found on the Indian subcontinent, central and northern Europe, Japan, Brazil, Mexico, and the United States. Topaz is found in a wide range of colors include yellow, peach, pink and of course blue. Naturally occurring blue topaz often has a fairly light color. The stone is sometime irradiated to increase the intensity of the color.
Topaz today is used to make a wide range of fashion jewelry including earrings, silver pendants, necklaces, and cuff links. The mild coloring of the gemstone makes it suitable for use in jewelry for women and men. Topaz jewelry is suitable for several occasions including November birthdays and wedding anniversaries. Topaz crystals are difficult to cut and polish due to the typical presence of basal cleavage. The popularity of topaz in fashion jewelry of today may be attributed to its relatively low cost, the range of colors available, and the ability to modify these naturally occurring colors through heat and radiation treatment. A more recent development is the making of Mystic Fire Topaz or Rainbow Topaz. In this process, a coating is applied to high quality white topaz. This coating gives the appearance of iridescence, with different colors displayed depending on the light source and the viewing angle. The coating is essentially permanent under normal wear conditions.
The folklore associated with topaz goes back to the Middle Ages, when the stone was believed to protect the wearer against physical and mental harm. Ancient Greeks believed that topaz could make the wearer invisible! Ancient Greek and Egyptian civilizations believed that topaz was related to the sun god, and therefore signified strength. Topaz is believed to balance emotions, promote calmness, and enhance positive feelings such as joy. Yellow topaz is the birth stone for November, and blue topaz is the birthstone for December. Topaz is the suggested gift for the 4th, 19th and 23rd wedding anniversaries.
Topaz has a hardness of about 8, and can therefore scratch other softer gemstones and jewels. It is recommended that different gemstones be separated from each other when being stored. Topaz can change color when exposed to heat and/or sunshine for extended periods of time. Therefore, prolonged exposure to these elements is not recommended. Topaz can we cleaned with warm water and a phosphate-free soap.
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