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Topaz

  • Color: blue, yellow, pink, red, brown, green, colorless
  • Hardness: 8
  • Refractive index: 1.60 - 1.64
  • Density: 3.50 - 3.58
  • Chemical composition: Al2[SiO4](F,OH)2
  • Crystal structure: orthorhombic
  • Origins: Brazil, Madagascar, Russia, USA, Mexico, Pakistan.

The most valued color for a topaz is orangey-pink (an example being the imperial topaz from Brazil). Heat treatment is common for yellowish stones, with light blue or colorless stones being subjected to x-ray treatment and heating. Very big, clean crystals are common. Topaz prices subject to noticeable variation due to fashion trends on local markets.

 

Topaz 51.00 cts. Topaz 6.98 cts.
Topaz 51.00 cts.
Published under permission: Miguel Angel Lopez
Topaz 6.98 cts.
Published under permission: Miguel Angel Lopez
Topaz 9.50 cts. Topaz 20.40 cts.
Topaz 9.50 cts.
Published under permission: Miguel Angel Lopez
Topaz 20.40 cts.
Published under permission: Miguel Angel Lopez

 


Market values of Topaz  

Occurrence of Topaz  

Historical values  


 
 
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