Dolomite

Big Photo

Brazil
16.39 carats
© Rarestone.com

Dolomite is named after Déodat Gratet de Dolomieu, who described its characteristics and occurences.

Dolomite forms white, gray to pink rhombohedral crystals, some of them exhibit curved growth, possibly a result of twinning. It can also be massive. Small amounts of iron in the structure cause a yellow to brown tint. A high manganese content gives the crystals a rosy pink colour.

Dolomite Gemstones by Colour

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

Dolomite Gemstones by Size

This table shows distribution of Dolomite 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:6.67 cts
Heaviest:16.39 cts
Average:9.92 cts
Total photos:4
Do you have a larger Dolomite? Why not upload a photo?
6.67ct to 7.64ct7.64ct to 8.61ct8.61ct to 9.59ct9.59ct to 10.56ct10.56ct to 11.53ct11.53ct to 12.50ct12.50ct to 13.47ct13.47ct to 14.45ct14.45ct to 15.42ct15.42ct to 16.39ct
General Information
Chemical Formula
CaMg(CO
 
3
)
 
2
Michael O’Donoghue, Gems, Sixth Edition (2006)
More from other references
Photos of natural/un-cut material from mindat.org
Physical Properties of Dolomite
Mohs Hardness3.5 to 4
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Specific Gravity2.80 to 2.95
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
TenacityBrittle
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Cleavage QualityPerfect
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
FractureSub-Conchoidal
Arthur Thomas, Gemstones (2009)
Heat SensitivitySensitive to heat
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Optical Properties of Dolomite
Refractive Index1.498 to 1.681
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Optical CharacterUniaxial/-
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Birefringence0.179 to 0.181
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) DoublingMore from other references
PleochroismNil
Arthur Thomas, Gemstones (2009)
DispersionLow
Arthur Thomas, Gemstones (2009)
Colour
Colour (General)White, yellowish, brownish
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004) Commonly bandedMore from other references
TransparencyTransparent,Translucent,Opaque
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
LustreVitreous,Pearly
Arthur Thomas, Gemstones (2009)
Fluorescence & other light emissions
Fluorescence (General)Inert to light orangy, bluish, greenish
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Crystallography of Dolomite
Crystal SystemTrigonal
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
HabitRhombohedral, massive
Michael O’Donoghue, Gems, Sixth Edition (2006)
More from other references
Geological Environment
Where found:Dolomite occurs in a number of conditions: in sedimentary rocks, in altered Mg-rich igneous rocks or in geodes.
Michael O’Donoghue, Gems, Sixth Edition (2006)
Further Information
Mineral information:Dolomite information at mindat.org
Significant Gem Localities
Spain
 
  • Navarre
    • Esteríbar
      • Eugui
Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 406
Gems, Sixth Edition, Michael O’Donoghue, 2006, p. 406
Copyright © Jolyon & Katya Ralph 1993-2014. 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.