“Mandarin Orange Spessartite Garnets from Africa.” © Dan Stair Custom Gemstones. Used with permission.
While the colors of spessartine or spessartite garnet gemstones cover a wide range of orange shades, the mandarin garnet is as pure orange as this variety can be. Discovered in Namibia in the 1990s, this rare gem is highly desired as a jewelry stone for its eye-catching color, brilliance, and hardness.
Mandarin Garnet Value
The International Gem Society (IGS) has a list of businesses offering gemstone appraisal services.
Mandarin Garnet Information
| Data | Value |
| Name | Mandarin Garnet |
| Is a Variety of | Spessartite |
| Crystallography | Isometric |
| Refractive Index | 1.789 - 1.797 |
| Colors | Orange |
| Luster | Vitreous |
| Fracture | Conchoidal |
| Hardness | 7 - 7.5 |
| Toughness | Good |
| Specific Gravity | 4.09 - 4.15 |
| Cleavage | None |
| Dispersion | 0.027 |
| Spectral | Lines at 4080, 4210, 4300, 4570, 4830, and 5270. |
| Wearability | Good |
| Transparency | Transparent, translucent |
| Birthstone | January (Garnet) |
| Formula | Mn3Al2Si3O12 |
| Etymology | After the color, “mandarin orange.” |
| Occurrence | Schist, gneiss |
| Inclusions | Curved fibers; round and angular crystals: quartz, fibrous amphibole, barite; oxide minerals |
“Spessartine Garnet” on schist matrix, Marienfluss, Kunene Region, Namibia. © Rob Lavinsky, www.iRocks.com. Used with permission.
Comments
Mandarin garnet is unequivocally orange, but its exact definition can vary. “Mandarin garnet” has been used as a trade name for vivid orange spessartite garnets from Namibia as well as a trade name for all spessartite garnets that possess that color. In the mid 1990s, the only garnets that fit either description were from Namibia. Like other garnets, these gemstones were mixed species. Their average composition is 85 mol.% spessartite, 12.5 mol.% pyrope garnet, and 2.5 mol.% grossular garnet. The high manganese (Mn) content of spessartite is what creates their striking orange color. In Nigeria in 1998, gem-quality spessartite was discovered with an orange color that approaches that of the Namibian material and is 95 mol.% spessartite. In 2007, gem-quality orange spessartite was discovered in Tanzania with a composition very close to the Namibian stones: 77.5 mol.% spessartite, 17.9 mol.% pyrope, and 4.6 mol.% grossular.
Whether defined by color, source, or chemical composition, Mandarin garnets made a splash in the jewelry world. Spessartite garnets are rare, and facetable material rarer still. The discovery of these gem-quality African gemstones meant jewelers and consumers could explore and enjoy the brilliance of these garnets.
Synthetics
Mandarin garnet has not been synthesized. However, orange glass and as well as orange yttrium aluminium garnet (YAG), a synthetic garnet, have been used as simulants.
Enhancements
These gemstones do not normally receive any treatments or enhancements, which makes them very desirable to collectors and enthusiasts of natural gems.
“Spessartine Garnet,” mandarin orange crystal, Loliondo, near Serengeti National Park, Tanzania. © Rob Lavinsky, www.iRocks.com. Used with permission.
Sources
- Namibia (Northwest): Marienfluss, Kunene Region
- Nigeria, Tanzania.
Stone Sizes
Mandarin garnets greater than 10 carats are extremely rare. At the Tucson Gem and Mineral Show in 1995, Colgem displayed a faceted, cushion-shape 29.77-ct stone and an eye-clean triangular mix-cut 14.77-ct stone. The Houston Museum of Natural Science has a gold ring with a faceted 39.35-ct mandarin garnet on display.
Trade Names
When first discovered, mandarin garnets were sold as “hollandines” and “Kunene spessartines.”
Care
The use of warm water, detergent, and a soft brush is the recommended cleaning method for all garnets. Consult our gem care guide and jewelry cleaning guide for more information.
“Garnet Ring with Cognac Diamonds,” 39.35-ct mandarin garnet, designed and created by Ernesto Moreira, Houston Museum of Natural Science, by Assignment Houston One is licensed under CC By-SA 2.5
