Star Sapphire

Big Photo

Sri Lanka
6.32 carats
© Palagems

Star Sapphire is a variety of Sapphire that exhibits a star pattern, so called asterism, which is caused by oriented microscopic inclusions.

Star Sapphire Gemstones by Colour

This table shows the variety of hues this gemstone can be found in. Click on a photo for more information.
 
 
 
 
 
 

Star Sapphire Gemstones by Size

This table shows distribution of Star Sapphire gemstone sizes that are listed on this site. This can give a good indication as to the general availability of this gemstone in different sizes.
Contributed photos
Lightest:1.07 cts
Heaviest:563.35 cts
Average:16.17 cts
Total photos:50
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Significant stones
Black Star of Queensland, Star Sapphire733 cts
1.07ct to 57.30ct57.30ct to 113.53ct113.53ct to 169.75ct169.75ct to 225.98ct225.98ct to 282.21ct282.21ct to 338.44ct338.44ct to 394.67ct394.67ct to 450.89ct450.89ct to 507.12ct507.12ct to 563.35ct
General Information
A variety or type of:Sapphire, which is a variety of Corundum
Chemical Formula
Al
 
2
O
 
3
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Significant stones
ImageNameWeightCountry of OriginCurrent Owner
Black Star of Queensland, Star Sapphire733.00 ctsAustraliaSmithsonian Institute
Star of India563.35 ctsSri Lanka
Star of Asia330.00 ctsMyanmar
Midnight Star116.75 ctsSri Lanka
Photos of natural/un-cut material from mindat.org
Star Sapphire Simulants
Star sapphire is imitated by using star rose quartz with blue enamel on a flat back; alternatively the star is engraved on the flat back of a synthetic cabochon or on glass. - Gemstones of the world, Walter Schumann, 2001, p 89
Physical Properties of Star Sapphire
Mohs Hardness9 to 0
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Specific Gravity3.90 to 4.05
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Optical Properties of Star Sapphire
Refractive Index1.758 to 1.780
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Optical CharacterUniaxial/-
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Birefringence0.007 to 0.010
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
ChatoyancyAsteriated (6/12). The chatoyancy is due to oriented microscopic inclusions.
Gemdat.org, Management Team (2012)
Colour
Colour (General)Pink, orange, yellow, green, blue, violet, colourless
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
TransparencyTransparent,Translucent,Opaque
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Crystallography of Star Sapphire
Crystal SystemTrigonal
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
Further Information
Mineral information:Star Sapphire information at mindat.org
Significant Gem Localities
Myanmar
 
  • Mandalay Region
    • Pyin-Oo-Lwin District
        • Bernardmyo
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
        • Chaung-gyi
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
        • Kathé (Kathe)
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
        • Kyatpyin Central
Ted Themelis (2008) Gems & mines of Mogok
        • Kyauk-Pyat-That
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
          • Yadanar-kaday-kadar
Ted Themelis (2008) Gems & mines of Mogok
        • Marble Ark
Ted Themelis (2008) Gems & mines of Mogok
          • Kyauk-poke (Rotten Stone)
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
        • Mogok Valley
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
  • Sagaing Region (Sagaing Division)
    • Katha District
      • Wuntho Township
Ted Themelis (2008) Gems & mines of Mogok
Sri Lanka
 
  • Sabaragamuwa Province
    • Ratnapura District
      • Ratnapura
Econ Geol (1981) 76:733-738
Thailand
 
  • Chanthaburi Province
http://www.mindat.org/article.php/262/Henry+Louis%3A+Ruby+and+Sapphire+Deposits+of+Moung+Klung+%28Thailand%29
Copyright © Jolyon & Katya Ralph 1993-2018. Site Map. Locality, gem & photograph data are the copyright of the individuals who submitted them. For more information please contact the . Gemdat.org is an online information resource dedicated to providing free gemmological information to all.