Gem Library

BUYER’S OVERVIEW:
Demantoid is considered to be a semi-precious gemstone. Very limited in nature, clear, natural stones are available but large stones are very rare and gems do not often exceed 2 carats. Rarity, beauty and durability are the definition of a fine gemstone, add dispersion or fire and you have a Demantoid. When you hold a gemstone and turn it in the light, some will display flashes of color, called dispersion. Diamond is famed for this quality, but Demantoid has a higher dispersion value than diamond. The luster of Demantoid is adamantine which means “like diamond”. Few gems have this luster, only Diamond, Sphene and Demantoid Garnet (the name means “diamond-like”). A fine Demantoid is a fantastic display of light.

COLOR:
Demantoid comes in light to dark green to yellow green.

APPEARANCE:
Transparent to translucent, Demantoid is usually included.

SIZE RANGE:
Melee (0.01 carat) sizes to 2 carats, high quality stones over 1 carat are scarce and over 2 carats are very rare.

TYPICAL CUTTING STYLES:
Transparent: most cutting styles are available.
Translucent: most cutting styles are available.

POSSIBLE ENHANCEMENTS & TREATMENTS:
Demantoid has no known enhancements.

HARDNESS:
6½ to 7 on the Mohs scale.

BEST USE OF THE GEMSTONE:
Demantoid is not a strong gemstone and as such, earrings, pendants, pins, and tie tacks are probably the safest choice for this stone. Rings should be limited to occasional wear and the stones should be set with a protective setting.

CARE & CLEANING:
It is best to never expose colored gemstones to cleaning solvents or chemicals of any kind.
Common cleaning methods include:
Ultrasonic: never
Steamer: never
Warm soapy water: safe
Reaction to Chemicals: can be damaged by acids.
Reaction to Heat: abrupt temperature changes may cause fractures
Stability to Light: stable

INTERESTING FACTS ABOUT THIS GEMSTONE:
Demantoid belongs to the Andradite sub-group of the garnet family and while garnets are regarded by some as rather common gemstones, many of the world’s rarest and expensive gemstones, including Mandarin Garnet (Spessartite), Tsavorite and Demantoid are actually members of the garnet family. The name Demantoid means “diamond-like” luster and in fact, Demantoid has a greater refractive index than sapphire and ruby. Only zircon and diamond are more brilliant, however, Demantoid has more dispersion or fire than diamond.

Demantoid garnet was discovered in 1853 in the Ural Mountains of Russia and Russia remained the only source of Demantoid until 1996 when a new deposit was discovered in Nambia. The African material was a slightly different color with the Russian material being yellowish-green and the African more gray green to green. Another clear distinction is that the Russian Demantoid often has feathery golden thread inclusions that tend to curve and resemble the tail of a horse. This “horsetail” inclusion is not present in any Demantoid other than the material from the Ural Mountains and the presence of a horsetail inclusion in the gemstone significantly increases its value. Demantoid is a very rare gem of fine clear green color with more fire than a diamond and until the discovery of the new material in Namibia this gem was thought to be virtually extinct. It is a very rare gem and a must for any gem lover.



DESIGNATION:
Demantoid is a garnet and is the birthstone for January and 2^nd wedding anniversary.

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