Diaspore

Big Photo

Turkey
0.57 carats
© gemselect.com

Diaspore is named from Greek "diaspheirein" - to scatter, alluding to its usual descrepitation when strongly heated.

Diaspore forms greenish-brown, yellow, colourless, sometimes pinkish or white platy crystals with vitreous lustre. Some specimens may show a slight colour change from greenish in daylight to pinkish brown under tungsten light.

Mamaris area in Mugla Province, Turkey seems to be the source of all large gem-quality crystals that have been faceted to date.

Diaspore Gemstones by Colour

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

Diaspore Gemstones by Size

This table shows distribution of Diaspore 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:0.55 cts
Heaviest:15.06 cts
Average:3.44 cts
Total photos:33
Do you have a larger Diaspore? Why not upload a photo?
0.55ct to 2.00ct2.00ct to 3.45ct3.45ct to 4.90ct4.90ct to 6.35ct6.35ct to 7.81ct7.81ct to 9.26ct9.26ct to 10.71ct10.71ct to 12.16ct12.16ct to 13.61ct13.61ct to 15.06ct
General Information
Varieties/Types:
Colour-change diaspore - Diaspore showing a noticable colour change effect.
Chemical Formula
AlO(OH)
Walter Schumann, Gemstones of the world (2001)
More from other references
Photos of natural/un-cut material from mindat.org
Physical Properties of Diaspore
Mohs Hardness6.5 to 7
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Specific Gravity3.30 to 3.40
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
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Cleavage QualityPerfect
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) Perfect and easyMore from other references
Optical Properties of Diaspore
Refractive Index1.702 to 1.750
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Optical CharacterBiaxial/+
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
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Birefringence0.048
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) DoublingMore from other references
ChatoyancyRare
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Colour
Colour (General)Greenish-brown, colourless, white, yellow, bluish, pink.
Walter Schumann, Gemstones of the world (2001)
More from other references
Colour (Daylight)Greenish
Michael O’Donoghue, Gems, Sixth Edition (2006)
Colour (Incandescent Light)Pinkish brown under tungsten light
Michael O’Donoghue, Gems, Sixth Edition (2006)
TransparencyTransparent,Translucent
Walter Schumann, Gemstones of the world (2001)
More from other references
LustreVitreous,Pearly
Walter Schumann, Gemstones of the world (2001) On cleavage surfaces mother-of-pearl lustre.
Crystallography of Diaspore
Crystal SystemOrthorhombic
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
HabitPlaty crystals
Michael O’Donoghue, Gems, Sixth Edition (2006)
Geological Environment
Where found:Diaspore may be formed by the hydrothermal alteration of aluminous minerals and may be a hydrothermal mineral in some alkalic pegmatites.
Michael O’Donoghue, Gems, Sixth Edition (2006)
Spectrographic Data
Calculated Spectra:
Click spectra for more information
Colour-change diaspore - Locality: Turkey
Further Information
Mineral information:Diaspore information at mindat.org
Significant Gem Localities
Turkey
 
  • Aegean Region
    • Muğla Province
      • Yatağan
Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 304
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