The demantoid garnet is also very soft as compared with emerald (61⁄2 as against nearly 8).
The demantoid garnet (sometimes called "olivine" in the trade).
The luster, too, is diamond-like as the name "demantoid" signifies.
Perhaps the adoption of the name "demantoid" might relieve the situation.
demantoid is regarded as a lime-iron garnet, coloured probably by a small proportion of chromium.
Green garnets are of two kinds, the calcium-iron garnet, known as demantoid, and the calcium-chromium garnet known as uvarovite.
The hardness is only 6.5, or lower even than that of quartz—a character rather adverse to the use of demantoid as a gem.
The stones are frequently referred to as "demantoid garnets" on account of their diamond-like luster and dispersion.