Antigorite

Big Photo

China
6.76 carats
© Rarestone.com

Antigorite is named after its discovery locality, in the Valle Antigorio, Piemonte, Italy.

Antigorite is a hard compact type of Serpentine. It occurs in tough pleated masses. The material is usually dark green in colour, but may also be yellowish, gray, brown or black.

Antigorite Gemstones by Colour

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

Antigorite Gemstones by Size

This table shows distribution of Antigorite 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:4.37 cts
Heaviest:6.76 cts
Average:5.57 cts
Total photos:2
Do you have a larger Antigorite? Why not upload a photo?
4.37ct to 4.61ct4.61ct to 4.85ct4.85ct to 5.09ct5.09ct to 5.33ct5.33ct to 5.57ct5.57ct to 5.80ct5.80ct to 6.04ct6.04ct to 6.28ct6.28ct to 6.52ct6.52ct to 6.76ct
General Information
A variety or type of:Serpentine
Varieties/Types:
Bowenite - Apple-green variety of Antigorite.
Williamsite - Oil-green variety of Antigorite.
Chemical Formula
(Mg,Fe
2+
 
)
 
3
Si
 
2
O
 
5
(OH)
 
4
Anthony et al, Handbook of mineralogy (2001)
Photos of natural/un-cut material from mindat.org
Physical Properties of Antigorite
Mohs Hardness5 to 5.5
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Specific Gravity2.58 to 2.80
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Cleavage QualityPerfect
Anthony et al, Handbook of mineralogy (2001)
FractureConchoidal,Splintery
Anthony et al, Handbook of mineralogy (2001)
Optical Properties of Antigorite
Refractive Index1.530 to 1.575
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Optical CharacterBiaxial/-
Anthony et al, Handbook of mineralogy (2001)
Colour
Colour (General)Green, blue-green, white; colorless to pale green in thin section.
Anthony et al, Handbook of mineralogy (2001)
TransparencyTranslucent,Opaque
Anthony et al, Handbook of mineralogy (2001)
LustreWaxy,Silky,Resinous,Greasy,Dull (Earthy)
Anthony et al, Handbook of mineralogy (2001)
Crystallography of Antigorite
Crystal SystemMonoclinic
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
HabitMinute crystals, typically platy, rarely elongated; some plates have rectangular outline due to cleavage; commonly bladed or fibrous.
Anthony et al, Handbook of mineralogy (2001)
Geological Environment
Where found:Commonly replaces ultramafic rocks, pervasively or in crosscutting veinlets. As a replacement of siliceous dolostone along contacts with diabase sills
Anthony et al, Handbook of mineralogy (2001)
Further Information
Mineral information:Antigorite information at mindat.org
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