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Faceted Topaz
Topaz is a common gemstone that has been used for centuries in jewelry. Its golden brown to yellow color
is classic but is confused with the less valuable citrine, which is sold under the name topaz. The blue topaz that is often
confused with aquamarine is rarely natural and is produced by irradiating and then heating clear crystals. Topaz is the November
birthstone.
The structure of Topaz is controlled by a chain like structure of connected irregular octahedrons. These octahedrons
have an aluminum in the middle surrounded by four oxygens. Above and below the aluminum are the hydroxide or fluoride ions.
The chains of octahedrons are held together by individual silicate tetrahedrons but it is the octahedron chains that give
topaz its crystalline shape. Topaz is the hardest silicate mineral and one of the hardest minerals in nature. However it has
a perfect cleavage which is perpendicular to the chains and is caused by planes that break the weaker Al-O, Al-OH and Al-F
bonds. None of the stronger Si-O bonds cross these planes. Topaz crystals can reach incredible size of several houndred pounds.
Topaz can make very attractive mineral specimens due to their high luster, nice colors and well formed and multifaceted crystals.
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Beautiful light blue brilliant VVS 7x9 oval, 2.85 cts.
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Nice light blue VVS 7x9 oval, 2.35 cts.
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Awesome light blue VVS 6x12 marquise, 2.25 cts. Fantastic stone!
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Beautiful pair of 3x6 VVS marquise-cut light blue stones. .6 ct total
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Extremely beautiful fancy-cut triangular silver topaz. Size: 15.5x11, and weighs a whopping 6.91 cts!
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Icredible fancy-cut triangular silver topaz that truly sparkles! Approx. size is 16x10.5 and it weighs a total
of 5.07 cts.
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