Grossular dodecahedron, 7 mm across, from Coahuila, Mexico
General
Category
Nesosilicate
Formula (repeating unit)
Ca3Al2(SiO4)3
IMA symbol
Grs[1]
Strunz classification
9.AD.25
Crystal system
Cubic[2]
Crystal class
Hexoctahedral (m3m) H-M Symbol: (4/m 3 2/m)
Space group
Ia3d
Identification
Color
light to dark green, light to dark yellow to reddish brown, brown, orange, red, yellow, green, white, occasionally translucent to opaque pink. It is also but rarely
found in colorless form[2]
Cleavage
none
Fracture
conchoidal to uneven[2]
Mohs scale hardness
6.5 to 7[2]
Luster
greasy to vitreous[2]
Streak
Brown
Specific gravity
3.61 (+.15/−.04)
Polish luster
vitreous[2]
Optical properties
Single refractive, often anomalous double refractive[2]
Refractive index
1.740 (+.12/−.04)[2]
Birefringence
none
Pleochroism
none
Dispersion
.028
Ultraviolet fluorescence
near colorless to light green – inert to weak orange in longwave and weak yellow-orange in shortwave; yellow – inert to weak orange in longwave and shortwave[2]
Absorption spectra
Hessonite sometimes shows bands at 407 and 430nm
Major varieties
Hessonite
yellow-red to reddish-orange
Tsavorite
intense green to yellowish green
Leuco-garnet
transparent and colorless[3]
Rosolite
translucent to opaque pink grossularite crystals in marble from Mexico
Grossular is a calcium-aluminium species of the garnet group of minerals. It has the chemical formula of Ca3Al2(SiO4)3 but the calcium may, in part, be replaced by ferrous iron and the aluminium by ferric iron. 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. Grossular is a gemstone.
In geological literature, grossular has often been called grossularite. Since 1971, however, use of the term grossularite for the mineral has been discouraged by the International Mineralogical Association.[4]
^ abcdefghiGIA Gem Reference Guide; Gemological Institute of America; 1995; ISBN 0-87311-019-6
^Cite error: The named reference MGKGross was invoked but never defined (see the help page).
^International Mineralogical Association (1971). "International Mineralogical Association: Commission on new minerals and mineral names" (PDF). Mineralogical Magazine. 38 (293): 102–105. Bibcode:1971MinM...38..102.. doi:10.1180/minmag.1971.038.293.14.
Grossular is a calcium-aluminium species of the garnet group of minerals. It has the chemical formula of Ca3Al2(SiO4)3 but the calcium may, in part, be...
composition. The different species are pyrope, almandine, spessartine, grossular (varieties of which are hessonite or cinnamon-stone and tsavorite), uvarovite...
Tsavorite or tsavolite is a variety of the garnet group species grossular, a calcium-aluminium garnet with the formula Ca3Al2Si3O12. Trace amounts of...
ugrandite group alongside the other calcium-bearing garnets andradite and grossular. Uvarovite is the rarest of the common members of the garnet group, and...
endmembers of the hydrogarnet family (grossular, hibschite, and katoite) depend on the degree of substitution (x): grossular: x = 0 hibschite: 0.2 < x < 1.5...
ugrandite garnets have Ca2+ in the X position: uvarovite (Ca3Cr2(SiO4)3), grossular (Ca3Al2(SiO4)3) and andradite (Ca3Fe2(SiO4)3). While there are two subgroups...
Beverage Milk Food Apple pie Fossil Woolly mammoth, beluga whale Gemstone Grossular garnet Mineral Talc Rock Granite, marble, slate Soil Tunbridge State route...
temperature (TN=11 K). Black crystals of andradite: melanite Almandine Geology Grossular Mineral Mineral collecting Pyrope Spessartine Tsavorite Uvarovite Warr...
paragneisses include clinopyroxene-hornblende-bearing psammites, garnet (grossular)-diopside marbles, and biotite-graphite phyllites. Near the memorial to...
Rodingite is a metasomatic rock composed of grossular-andradite garnet, calcic pyroxene, vesuvianite, epidote and scapolite. Rodingites are common where...
Garnet(Almandine, Rhodolite, Pyrope, Demantoid, Tsavorite, Hessonite, Grossular, Spessartine) Course notes at the Department of Geological Sciences, The...
"frog-eyes" of 1.8 cm each sit perched atop a matrix Andradite Gemstone Grossular Mineral collecting Pyrope Tsavorite Uvarovite Warr, L.N. (2021). "IMA–CNMNC...
occurs associated with vesuvianite, chlorite, magnetite, rutile, diaspore, grossular, calcite, diopside and clinozoisite in various locations. Amesite is an...
Discovered the 1960s, the rich green tsavorite variety of grossular is also very popular. Both grossular and andradite are isotropic and have relatively high...
published 1929–1950 Rosin, also called colophony, a solid form of resin Grossular, also called colophonite, a mineral All pages with titles beginning with...
grossulars (viluites) in a serpentinized skarn. The minerals that wiluite and viluite refer to have often been confused, and may refer to grossular,...
epidote, pargasite, tourmaline, garnet (alamandine), peridot, turquoise, grossular, quartz (citrine and other varieties) and vesuvianite. The export earned...
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