The Gemstone Garnet

Pyrope Garnet

Garnet is not a single mineral, but describes a group of several closely related minerals. Garnets come in a variety of colors and have many different varieties. However, the most widely-known color of Garnet gemstones is dark red. When the term "Garnet" is used, it is usually connotative of the dark red form; other color Garnets are usually given more descriptive gemstone terms.

The properties below are generic to all Garnets; see the specific Garnet gemstone pages for more precise details.


? Red, Green, Yellow, Orange, Brown, Pink, Purple, Gray, Black


? 6.5 - 8.5

Chemical Formula

? Garnet is a series of several different minerals with unique chemical formulas. See The chemical formula of Garnet for details.

Mineral Class

? Garnet

Additional Properties

Crystal System
? Isometric
Refractive Index
? 1.780 - 1.889
Double Refraction
? None
? Transparent to translucent
? 3.5 - 4.3
? Vitreous; some forms adamantine or submetallic
Cleavage ? None. May exhibit parting.

All About

Almandine and Pyrope are the most widely used Garnet gemstones. Though Almandine is the most common Garnet, it is usually opaque and not fit for gemstone use. Only the less common transparent dark red forms of Almandine are used as gemstones. Pyrope is especially noted for its transparency and frequent lack of flaws or inclusions. A rose-red to violet variety of Pyrope (or intermediary between Almandine and Pyrope) is known as Rhodolite, and is a very well represented in the gem trade.

Spessartite is an orange to orange-red form of Garnet, and has recently increased in popularity, with several new deposits of gem grade material having been recently exploited. Grossular, the most varicolored form of Garnet, has the important gem variety of green Tsavorite, as well as orange-brown Hessonite and a yellow to yellow-green form.

Andradite, the most lustrous of the Garnets, has the rare green Demantoid variety, the yellow Topazolite variety, and the black Melanite variety. Uvarovite, the rarest of the familiar garnets, is seldom found in crystals large enough to be faceted, and is the least represented of all the familiar Garnets.

Color-changing Garnet is an interesting form of this gemstone that has a different color when viewed in natural and incandescent lighting. It can have several color combinations, especially brown or orange in daylight to a pink or light red in incandescent light.

Garnets occasionally displays asterism in the form of four-rayed stars. However, Star Garnets are very rare, and generally occur in opaque stones with only a weak asterism effect; thus interest in Star Garnets are limited.


? Garnet is a very popular gemstone, and is the most well-known dark red gemstone. Red Garnet gemstones (Almandine and Pyrope) are very affordable and faceted into all types of jewerly, including necklaces, rings, bracelets, and earrings. Round cabochons of red Garnet are also popular and used in rings and bracelets. The variety Rhodolite has become a very important jewelry gemstone, and the rare green Tsavorite and Demantoid Garnets make exquisite and costly gemstones. Color Changing Garnet has sparked recent interest, and it is most often used in rings. Other forms of Garnets such as orange Spessartite, yellow Grossular and black Melanite are also used as gemstones.

Garnet is the birthstone for January.

Other Names



There are many forms and varieties of Garnets. The six main Garnet mineral types are:
The list below are more general Garnet variety names that are commonly used:

Treatments & Enhancements

? Garnet gemstones are not enhanced, and their colors are always natural. Treatments such as heat treatment and irradiation have proved ineffective upon the Garnet gemstones. Several synthetic Garnets are simulants of other gemstones. The most widely known synthetic Garnet is Yttrium Aluminium Garnet (YAG), Y3Al2(AlO4)3, and it is a colorless simulant of Diamond. Widely used until the 1970's, YAG has lost its stake Cubic Zirconia as a Diamond simulant. Gadolinium Gallium Garnet (GGG), Gd3Ga2(GaO4)3 is another synthetic Garnet form. It is rarely used as a gemstone though, and is most often produced for industrial and optical uses.

Garnet-doublets are made of a colored glass bottom with a Garnet gemstone fused to the top of the stone. Garnet doublets are rarely created anymore due to the affordability of Garnet gemstones.

Garnet Sources

? See the individual Garnet gemstone pages for specific localities of each Garnet type.

Similar Gemstones

? Due to the great color variations of Garnet, many other gemstones may be confused with it. In addition, many of the individual Garnet varieties can be similar to each other. View the individual Garnet gemstone pages for specific similar gemstones for each Garnet type.

Garnet Photos

The images below represent a single sample of each of the main Garnet gemstone forms and varieties. More photos can be found on the individual Garnet pages.

Garnet in the Rough Photos

The images below represent a single sample of each of the main Garnet gemstone forms and varieties. More photos can be found on the individual Garnet pages.

Garnet Jewelry Photos



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