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Carved garnet gem
MFA# 21.1213



A family of minerals composed of trisilicates with Aluminum, Iron, Calcium, Magnesium, Manganese, or Chromium. Garnets are found in deposits around the world as transparent crystals embedded in igneous and metamorphic rocks. They have been used as gemstones since antiquity. The ruby red Pyrope and the lighter red Almandine were the most highly prized varieties. The pale rose-purple Rhodolite is a mixture of pyrope and almandine. Garnets are also used as abrasives. The crushed, ground and cleaned garnet is sold as an abrasive powder, coated paper and coated cloth. Garnet particles have sharper cutting edges than aluminum oxide, but are expensive. To decrease costs, some commercially available garnet cloths are actually prepared with quartz. Sources of gem quality garnets include the Czech Republic, South Africa, Australia, China, India, Brazil, Sri Lanka, and the U.S (New York, Maine, Idaho).


Synonyms and Related Terms

pyrope (deep red to black); almandine (bright red to black); spessartine (orange to red to brown); grossularite (green); grossular (colorless); carbuncle; andradite (wine red); uvarovite (emerald green); tsavorite (green); rhodolite (pale red to purple); hessonite (golden); topazolite; demantoid; melanite; Uralian emeralds; Greek anthrax; Granat (Deut.); granate (Esp.); grenat (Fr.); granaat (Ned.); granada (Port.); granatus (Lat.)

Raman of Grossular (RASMIN)


Raman of Almandine (RRUFF)

Almandine Raman RRUFF R040079.png

Raman of Andradite (RRUFF)

Andradite Raman RRUFF R040001.png

Raman of Grossular (RRUFF)

Grossular Raman RRUFF R040065.png

Raman of Pyrope (RRUFF)

Pyrope raman RRUFF R040159.png

Raman of Spessartine (RRUFF)

Spessartine Raman RRUFF R050063.png

Raman of Uvarovite (RRUFF)

Uvarovite Raman RRUFF R061041.png

IR-ATR of Almandine (RRUFF)

Almandine IR-ATR R040079.png

IR-ATR of Andradite (RRUFF)

Andradite Infrared RRUFF R040001.png

IR-ATR of Grossular (RRUFF)

Grossular IR-ATR RRUFF R040065.png

Pyrope IR-ATR R040159.png

IR-ATR of Spessartine (RRUFF)

Spessartine IR-ATR RRUFF R050063.png

IR-ATR of Uvarovite (RRUFF)

Uvarovite IR-ATR RRUFF R061041.png

Physical and Chemical Properties

  • Isometric crystal system with dodecahedron and trapezohedron habits
  • Luster = vitreous to resinous
  • Fracture = conchoidal or uneven
  • Cleavage = indistinct
  • Streak = colorless to white
  • Fluorescence = none (except green or yellow stones that may give weak yellow-orange colors in LW and SW)
Mohs Hardness 6.5 - 7.5
Density 3.52-4.32 g/ml
Refractive Index 1.72-1.94
Birefringence none


Properties of Common Abrasives

Properties of Common Gemstones

Natural and Simulated Diamonds

Resources and Citations

  • Gem Identification Lab Manual, Gemological Institute of America, 2016.
  • Jack Odgen, Jewellery of the Ancient World, Rizzoli International Publications Inc., New York City, 1982
  • R.F.Symmes, T.T.Harding, Paul Taylor, Rocks, Fossils and Gems, DK Publishing, Inc., New York City, 1997
  • Encyclopedia Britannica, Comment: "garnet" [Accessed December 4, 2001]. (color photo)
  • C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
  • G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: Mohs hardness = 8
  • Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
  • Wikipedia: Garnet (Accessed Sept. 7, 2005 and Dec 2022)
  • CRC Handbook of Chemistry and Physics, Robert Weast (ed.), CRC Press, Boca Raton, Florida, v. 61, 1980 Comment: density=3.15-4.3
  • R.M.Organ, Design for Scientific Conservation of Antiquities, Smithsonian Institution, Washington DC, 1968
  • Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979

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