Grossular

Big Photo

Transvaal Jade
South Africa
8.39 carats
© Palagems

The name grossular is derived from the botanical name for the "gooseberry" - grossularia, in reference to the green garnet of this composition that is found in Siberia.

Other shades include cinnamon brown (cinnamon stone variety), red, and yellow.
133 photos

Grossular Gemstones by Colour

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

Grossular Gemstones by Size

This table shows distribution of Grossular 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:0.06 cts
Heaviest:23.21 cts
Average:3.22 cts
Total photos:127
Do you have a larger Grossular? Why not upload a photo?
0.06ct to 2.38ct2.38ct to 4.69ct4.69ct to 7.01ct7.01ct to 9.32ct9.32ct to 11.64ct11.64ct to 13.95ct13.95ct to 16.27ct16.27ct to 18.58ct18.58ct to 20.90ct20.90ct to 23.21ct
General Information
A variety or type of:Garnet Group
Varieties/Types:
Hessonite - A golden orange to brown variety of grossular.
Hibschite - A grossular containing hydroxyl ions.
Hydrogrossular - A grossular containing hydroxide (OH).
Transvaal Jade - A compact green massive jade-like variety of grossular.
Tsavorite - An emerald-green variety of grossular.
Chemical Formula
Ca
 
3
Al
 
2
(SiO
 
4
)
 
3
Arthur Thomas, Gemstones (2009)
Physical Properties of Grossular
Mohs Hardness7 to 7.5
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Specific Gravity3.55 to 3.73
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Cleavage QualityNone
Arthur Thomas, Gemstones (2009)
FractureConchoidal
Arthur Thomas, Gemstones (2009)
Optical Properties of Grossular
Refractive Index1.730 to 1.760
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
Optical CharacterIsotropic
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010) Anomalous double refractionMore from other references
Dispersion0.020
Walter Schumann, Gemstones of the world (2001)
More from other references
Colour
Colour (General)Colourless, yellowish-green, green, brown, yellow
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
Causes of ColourGreen (tsavorite), V3+ in octahedral coordination. Orange (hessonite), Mn2+ in distorted cubic coordination, Fe3+
W. William Hanneman, Pragmatic Spectroscopy For Gemologists (2011)
TransparencyTransparent
Ulrich Henn and Claudio C. Milisenda, Gemmological Tables (2004)
More from other references
LustreVitreous
Arthur Thomas, Gemstones (2009)
Fluorescence & other light emissions
Fluorescence (General)Dense grossular: strong - red-orange
Walter Schumann, Gemstones of the world (2001)
Fluorescence (Short Wave UV)Colorless to greenish: weak yellowish-green
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Fluorescence (Long-Wave UV)Colorless to greenish: weak orangy
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
Crystallography of Grossular
Crystal SystemIsometric
Herve Nicolas Lazzarelli, Blue Chart Gem Identification (2010)
More from other references
HabitDodecahedral, trapezohedral
Arthur Thomas, Gemstones (2009)
Inclusions in Grossular
Healing cracks, two-phase inclusions, crystal inclusions, growth lines - Gemmological Tables, Ulrich Henn and Claudio C. Milisenda, 2004, p 24
Further Information
Mineral information:Grossular information at mindat.org
Significant Gem Localities
Canada
 
  • Québec
    • Chaudière-Appalaches
      • Les Appalaches RCM
        • Saint-Joseph-de-Coleraine
Wilson (2007)
    • Estrie
      • Le Val-Saint-François RCM
        • St-Denis-de-Brompton
Wilson (2007)
      • Les Sources RCM
Amabili et al. (2004, 2008)
Amabili et al. (2004, 2008)
India
 
  • Rajasthan
    • Jhunjhunu District
Viswanatha (1982)
    • Jodhpur Division
      • Sirohi District
        • Deri-Ambaji Zn-Pb-Cu deposit
Viswanatha (1982)
Kenya
 
  • Taita-Taveta County
Kane et al. (1990)
      • Tsavo National Park
[var: Tsavorite] Keller (1992)
  • Turkana County
    • Lodwar
[var: Tsavorite] Barot (1993)
Madagascar
 
  • Atsimo-Andrefana
    • Ampanihy District
[var: Tsavorite] Laurs (2003)
Mali
 
  • Kayes Region
    • Bafoulabé Cercle
Brightman and Tunzi (1995)
    • Nioro du Sahel Cercle
      • Sandaré Commune
Dameron (2008)
Myanmar
 
  • Mandalay Region
    • Pyin-Oo-Lwin District
      • Mogok Township
        • Pein-Pyit (Painpyit; Pyan Pyit)
Ted Themelis (2008) Gems & mines of Mogok
Ted Themelis (2008) Gems & mines of Mogok
    • Yamethin District
[var: Hessonite] Ted Themelis (2008) Gems & mines of Mogok
Russia
 
  • Chelyabinsk Oblast
    • Kusinsky District
      • Magnitka
Evseev (1993)
  • Perm Krai
    • Gornozavodskii District
      • Sarany
Kolesar (1997)
  • Primorsky Krai
    • Dalnegorsk Urban District
Smith and Smith (1995)
  • Sakha
    • Mirninsky District
Evseev (1994)
Evseev (1994)
Evseev (1994)
  • Sverdlovsk Oblast
    • Asbest
Smith and Smith (1995)
South Africa
 
[var: Transvaal Jade]
Sri Lanka
 
  • Sabaragamuwa Province
    • Ratnapura District
      • Ratnapura
G. Zoysa (2009)
  • Uva Province
    • Monaragala District
[var: Hessonite] G. Zoysa (2009)
[var: Hessonite] G. Zoysa (2009)
Tanzania
 
  • Manyara Region
    • Simanjiro District
[var: Tsavorite]
Pardieu (2007)
Pardieu (2007)
USA
 
  • California
    • Siskiyou County
      • Klamath Mountains
        • Preston Peak
Gems & Minerals (1963): July: 20-22; USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10286810.
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