DEMANTOID

Photo courtesy of Gemsbynomads

Variety:  Demantoid
Species:  Andradite
Group:  Garnet
Mohs Hardness:  6.5 to 7 out of 10
Color:  Green to yellow green, with strong fire
RI:  OTL
Birefringence:  None
SR/DR/AGG:  SR, often with ADR
Clarity Type:  Type II
Pleochroism:  None
Spectrum:  A dark band at 443nm in yellowish green stones, or a cutoff below 443nm with fine lines at 620nm, 632nm, 693nm, and 700nm in rich green stones
Fluorescence:  Inert
Color Filter:  Pinkish to inert
SG:  3.84 (+/- 0.03)
Routine Treatments:  None

Demantoid Facts

Garnets occur in nearly every color.

Demantoid garnets range in color from green through yellowish green, and are known for their signature horsetail inclusions.
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While highly-included diamonds are less valuable, demantoids with horsetail inclusions can be much more expensive than those without.

Fine quality demantoids are considered to be the rarest, and most valuable of all garnets.
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