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CHAPTER V.
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Garnet Group—Essonite, Spessartite, Almandite, Pyrope, Ouvarovite, Schorlomite.
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• HE garnet represents a group of minerals which, although chemically quite different, crystallize in the isometric system. The following are the varieties that
Essonite, which has been confused with zircon, the only true hyacinth, is still called hyacinth by the jeweler. It has a hardness of 7 and its specific gravity is 3.68. Grossularite is the pale-green or yellowish variety of essonite.
Almandine garnets vary in color from violet or purple through brownish-red to deep red. The scarlet and the crimson varieties, when cut en cabochon, are called carbuncles. The finest alman-dines are from Siriam, India. Their hardness is 7.5 and specific gravity, 4.1 to 4.3.
Pyrope, or blood-red garnet, is commonly known from its use in cheap Bohemian jewelry and is found extensively at a number of places in Bohemia, and also of fine quality at the Kimberley Mines in South Africa. Its hardness is 7.5 and its specific gravity 3.7 to 3.8.
Ouvarovite is of a brilliant emerald-green color and is found at Bissersk, in Siberia, but is rarely large enough to furnish gem stones. Its hardness is nearly 8 and specific gravity 3*45.
Demantoid is a variety of green garnet called Bobrowsaka garnet or Uralian emerald, and is found near Poldnewaja, district
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