• WordNet 3.6
    • n demantoid a green andradite used as a gemstone
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Webster's Revised Unabridged Dictionary
    • n Demantoid (Min) A yellow-green, transparent variety of garnet found in the Urals. It is valued as a gem because of its brilliancy of luster, whence the name.
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Century Dictionary and Cyclopedia
    • n demantoid A light-green to emerald-green variety of garnet, found in the Ural mountains. It is transparent and of brilliant luster, and is classed as a gem.
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Webster's Revised Unabridged Dictionary
G. demant, diamond + -oid,


In literature:

The demantoid garnet (often unfortunately and incorrectly called "olivine" in the trade) is usually of an olive or pistachio shade.
"A Text-Book of Precious Stones for Jewelers and the Gem-Loving Public" by Frank Bertram Wade
Demantoid is regarded as a lime-iron garnet, coloured probably by a small proportion of chromium.
"Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 10" by Various