Light to Dark green and yellowish green
Optic Character: SR,
of Color: Cr,
: Concoidal to
Cleavage : None
(byssolite) inclusions, high dispersion
Italy, Korea, Rusia, Zaire
A Vaiety of Andradite Garnet
Ca3 Fe2 Si3 O12
Demantoid is a member of the garnet family. It is not only
the most expensive of the garnets, it is one of the most
expensive gems in the world! It is coveted for its rarity
and its incredible brilliance. Demantoid is more dispersive
than diamond. It's ability to break white light into rainbow
colors is unsurpassed.
Demantoid occurs in many shades of green and ranges from
slightly yellowish green to brownish green with a golden
shine. The rarest and most valuable is a deep emerald green.
Only a few stones achieve more than two carats after cutting.
Demantoids from the Urals often include the diagnostic inclusions
of asbestos fibres known as "horsetails". These
inclusions are desirable.
was first discovered in the Urals mountains in Russia