Taaffeite (Magnesiotaaffeite)

Big Photo

Musgravite
Tunduru, Tunduru District, Ruvuma Region, Tanzania
0.44 carats
© Mineral Classics

Taaffeite is named after E.C.R. Taaffe, gemologist of Dublin, Ireland.

Taaffeite forms mauve or lilac, red to brown, bluish, green transparent to translucent crystals.

A. Thomas reports that "Taaffeite is a very rare gem mineral that was first discovered as a cut stone". A light mauve stone was originally believed to be spinel. The source of the material was unknown for a long time, until eventually small fragents were found in Sri Lanka.

A purplish brown chatoyant taaffeite has been found recently in Sri Lanka.

Taaffeite Gemstones by Colour

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

Taaffeite Gemstones by Size

This table shows distribution of Taaffeite 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:0.44 cts
Heaviest:8.50 cts
Average:2.28 cts
Total photos:17
Do you have a larger Taaffeite? Why not upload a photo?
0.44ct to 1.25ct1.25ct to 2.05ct2.05ct to 2.86ct2.86ct to 3.66ct3.66ct to 4.47ct4.47ct to 5.28ct5.28ct to 6.08ct6.08ct to 6.89ct6.89ct to 7.69ct7.69ct to 8.50ct
General Information
Varieties/Types:
Musgravite - A trigonal mineral very closely related to taaffeite.
Other Names/Trade Names:
Chemical Formula
Mg
 
3
Al
 
8
BeO
 
16
Walter Schumann, Gemstones of the world (2001)
More from other references
Photos of natural/un-cut material from mindat.org
Physical Properties of Taaffeite
Mohs Hardness8 to 8.5
Walter Schumann, Gemstones of the world (2001)
More from other references
Specific Gravity3.60 to 3.62
Walter Schumann, Gemstones of the world (2001)
More from other references
FractureConchoidal
Arthur Thomas, Gemstones (2009)
Optical Properties of Taaffeite
Refractive Index1.716 to 1.730
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
Optical CharacterUniaxial/-
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
Birefringence0.004
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
PleochroismWeak
Arthur Thomas, Gemstones (2009)
Dispersion0.020
Arthur Thomas, Gemstones (2009)
Colour
Colour (General)Violet, colourless, pale green, bluish, pink, red.
Walter Schumann, Gemstones of the world (2001)
More from other references
Causes of ColourRed to violet, Cr3+ in octahedral coordination
W. William Hanneman, Pragmatic Spectroscopy For Gemologists (2011)
TransparencyTransparent
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
LustreVitreous
Walter Schumann, Gemstones of the world (2001)
Crystallography of Taaffeite
Crystal SystemHexagonal
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
HabitPrismatic
Arthur Thomas, Gemstones (2009)
Geological Environment
Where found:Occurs in gem gravels or in skarns at the contact between dolostones and limestones with beryllium-bearing granite.
Michael O’Donoghue, Gems, Sixth edition (2006)
Inclusions in Taaffeite
Healing cracks, crystal inclusions - Gemmological Tables, Ulrich Henn and Claudio C. Milisenda, 2004, p 22
Further Information
Mineral information:Taaffeite information at mindat.org
Significant Gem Localities
Sri Lanka
 
  • Sabaragamuwa Province
    • Ratnapura District
      • Ratnapura
Copyright © Jolyon & Katya Ralph 1993-2019. 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.