demantoid garnet - cushion cut, Madagascar
demantoid garnet - cushion cut, Madagascar

Demantoid Garnet Value, Price, and Jewelry Information


One of the rarest garnet varieties, demantoid can have a green color that rivals emerald and a fire that exceeds diamond. Demantoids are highly prized by both gem collectors and jewelry enthusiasts.

3 Minute Read

One of the rarest garnet varieties, demantoid can have a green color that rivals emerald and a fire that exceeds diamond. Demantoids are highly prized by both gem collectors and jewelry enthusiasts.

demantoid garnet - cushion cut, Madagascar
Modified square/cushion-cut demantoid garnet, 1.88 cts, 6.0 x 6.0 x 5.0 mm, Antetezambato, Ambanja District, Antsiranana Province, Madagascar. © Rob Lavinsky, www.iRocks.com. Used with permission.

Start an IGS Membership today

for full access to our price guide (updated monthly).

Demantoid Garnet Value

All Sizes
Almandine
to /ct

Become a member to unlock prices

Even with the discovery of new sources since the 1990s, demantoid remains very rare. It’s the most well-known andradite garnet and one of the most valuable garnets of any variety. Clean, facetable stones command very high prices per carat. However, demantoids with horsetail inclusions — wavy, golden, and fibrous — are especially coveted by collectors.

oval-cut demantoid - Russia
Brilliant, oval-cut demantoid with horsetail inclusions, 2.67 cts, 8.27 x 6.81 x 5.71 mm, Ural Mountains, Russia. © Rob Lavinsky, www.iRocks.com. Used with permission.

For more information on value and quality factors for demantoids, consult our buying guide.

demantoids - faceted set
Demantoids: Russia (1.93, 0.93, 4.37). Photo © Joel E. Arem, PhD, FGA. Used with permission.

What is Demantoid?

Demantoid was discovered in Russia in the early 19th century. In 1854, the noted mineralogist Nils Gustaf Nordenskiöld identified this gem as a variety of andradite garnet. These stones had such exceptional brilliance and dispersion or “fire” that they inspired Nordenskiöld to name demantoid after its “diamond-like” appearance.

Does Demantoid Make a Good Jewelry Stone?

Demantoid Brooch Pendant
Demantoid and diamond brooch-pendant, Moscow (1899-1908), collection V. Kirichenko. Photo by Shakko. Licensed under CC By-SA 3.0.

In fact, demantoid has greater brilliance and a higher dispersion than its diamond namesake as well as other well-known green gemstones, such as emerald and peridot. Although dark body colors can mask their dispersion, small demantoids with light colors are quite dazzling.

Like most garnets, demantoids can make excellent jewelry stones. However, some demantoids may have a hardness of 6.5, somewhat lower than most other garnets. This means they're somewhat susceptible to scratching. Therefore, use protective settings for these gems, especially if used as ring stones.

Demantoid was a popular gemstone during the Belle Époque period (1890-1915), especially in Art Nouveau jewelry. The Russian Czars particularly favored this gem.

Russia was long the only source of demantoids, but supplies ran so low, these gems were usually seen only in antique jewelry pieces. However, since the 1990s, new discoveries in Namibia, Madagascar, and other locations, as well as renewed mining in Russia, have made the gem more available. Today, demantoids are still desirable, but very expensive, jewelry stones.

3.80-ct demantoid - Namibia
3.80-ct demantoid, clarity VVSI, sourced near Karibib, Namibia. Photo © Claradyn Venter. Used with permission.

Do All Demantoids Have Horsetail Inclusions?

Horsetail inclusions of byssolite or chrysotile, usually golden in color, are named after their long, wavy appearance. These inclusions have long been considered diagnostic for identifying demantoids. However, a 2018 study found horsetail inclusions in non-demantoid (brown) andradite. Thus, horsetails may not be sufficient in and of themselves for identifying demantoids, nor do all demantoids have horsetails.

On very rare occasions, inclusions in demantoids may produce cat's eye gems.

0.38-ct demantoid with horsetail inclusions - Russia
Russian demantoid with horsetail inclusions, 0.38 cts, 4.3 x 3 mm. Photo courtesy of liveauctioneers.com and Jasper52.

How to Tell a Demantoid from an Emerald

Although demantoids may have an emerald-like color and included appearance, the optical and physical properties of these two distinct gem species differ considerably. Most visibly, demantoids have greater dispersion and no birefringence. (Note that some demantoids may show anomalous birefringence. A polariscope examination can help determine if a stone is truly birefringent).

Demantoid Garnet Madagadcar
Garnet on matrix (demantoid variety), 2.8 x 2.4 x 1.5 cm, Madagascar. © Rob Lavinsky, www.iRocks.com. Used with permission.

How to Tell Demantoids from Other Green Garnets

Like demantoids, tsavorites and uvarovites are rare garnet varieties with emerald-like color. However, the specific gravity (SG) and dispersion of demantoid exceed that of its green garnet brethren.

Are There Synthetic Demantoids?

Demantoid hasn't been synthesized, but green glass as well as green yttrium aluminum garnet (YAG), a synthetic garnet, have been used as simulants.

Demantoid Enhancements

Heating may improve demantoid color. This is a stable and undetectable treatment.

Where are Demantoids Found?

Historically and currently, Russia has been an important producer of demantoids. Notable gem sources include the Ural Mountains region, the Koryakskoe plateau, and the Kola Peninsula.

Since 1996 and 2009, respectively, Namibia and Madagascar have become commercially important sources.

2.15-ct demantoid - Namibia
2.15-ct demantoid, clarity IF, sourced near Karibib, Namibia. Photo © Claradyn Venter. Used with permission.

In Italy, Ala, Piedmont produces dark, apple-green material. Val Malenco, Sondrio Province also produces demantoids.

demantoids in asbestos matrix - Italy
This specimen features about a dozen demantoids on a fibrous asbestos matrix. The largest crystal measures about an inch across. 5.5 x 3.7 x 1.2 cm, Val Malenco, Sondrio Province, Lombardy, Italy. © Rob Lavinsky, www.iRocks.com. Used with permission.

Other notable sources of gem-quality demantoids include the following:

  • Afghanistan; Azerbaijan; Canada; Democratic Republic of the Congo; Iran; Mexico; Pakistan; South Korea; Sri Lanka; San Benito County, California, United States.
demantoid - Iran
Andradite (variety demantoid), 3.0 x 2.7 x 2.4 cm, Belqeys Mountain, near Takab, West Azerbaijan, Iran. © Rob Lavinsky, www.iRocks.com. Used with permission.

Stone Sizes

Demantoids are typically small stones. Stones larger than 10 carats are very rare. Faceted stones greater than 1 carat are rarely seen. The largest demantoid ever found hailed from the Russian Urals and weighed 252.5 carats or 50.5 grams.

The Smithsonian Institution has a faceted 11.24-carat specimen on display.

trilliant-cut demantoid - Madagascar
Modified trilliant-cut demantoid, 2.03 cts, 12.0 x 9.0 mm, Antetezambato, Ambanja District, Antsiranana Province, Madagascar. © Rob Lavinsky, www.iRocks.com. Used with permission.

Demantoid Trade Names

Consumers may encounter demantoids offered for sale under such names as “Siberian emeralds,” “Siberian chrysolites,” and “Ural chrysolites.” Of course, garnets constitute a distinct group of gem species from emeralds. “Chrysolite” is an archaic term for green to yellow-green gems that has been applied to peridots as well as chrysoberyls and prehnites. These gems also constitute species distinct from demantoids.

For more examples, consult our article on false or misleading gemstone names.

Demantoids - Russia
Demantoids from the Bobrovka River, Russia, on display at the Mineralogical Museum, Bonn, Germany. Photo by Elke Wetzig. Licensed under CC By-SA 3.0.

How to Care for Demantoids

Heat sensitive garnets, like demantoids, should be cleaned with warm water, detergent, and a soft brush. Avoid mechanical cleaning and exposure to extreme heat.

Consult our gemstone care guide and jewelry cleaning guide for more information.

Antique beetle pin - demantoids. red garnets, and diamonds
This antique beetle pin, circa 1870, features demantoids and diamonds, red garnets for the eyes, and unparalleled 14k craftsmanship. Russian demantoids ~ 0.25-0.50 cts. Photo © Joel E. Arem, PhD, FGA. Used with permission.

Joel E. Arem, Ph.D., FGA

Dr. Joel E. Arem has more than 60 years of experience in the world of gems and minerals. After obtaining his Ph.D. in Mineralogy from Harvard University, he has published numerous books that are still among the most widely used references and guidebooks on crystals, gems and minerals in the world.

Co-founder and President of numerous organizations, Dr. Arem has enjoyed a lifelong career in mineralogy and gemology. He has been a Smithsonian scientist and Curator, a consultant to many well-known companies and institutions, and a prolific author and speaker. Although his main activities have been as a gem cutter and dealer, his focus has always been education. joelarem.com


Donald Clark, CSM IMG

The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters “CSM” after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff’s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book “Modern Faceting, the Easy Way.”


International Gem Society

Never Stop Learning

When you join the IGS community, you get trusted diamond & gemstone information when you need it.

Become a Member

Get Gemology Insights

Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!