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Study Dictionary
Topaz
Topaz [EBD]
Heb. pitdah (Ezek. 28:13; Rev. 21:20), a golden yellow or "green" stone brought from Cush or Ethiopia (Job 28:19). It was the second stone in the first row in the breastplate of the high priest, and had the name of Simeon inscribed on it (Ex. 28:17). It is probably the chrysolite of the moderns.
Topaz [NAVE]
TOPAZA precious stone, Ezek. 28:13; Rev. 21:20.
In the breastplate, Ex. 28:17; 39:10.
Ethiopian, celebrated, Job 28:19.
TOPAZ [SMITH]
one of the gems used in the high priest?s breastplate, (Exodus 28:17; 39:10; Ezekiel 28:13) one of the foundations also of the New Jerusalem, in St. John?s description of the city. (Revelation 21:20) The topaz of the ancient Greeks and Romans is generally allowed to be our chrysolite, while their chrysolite is our topaz. Chrysolite is a silicate of magnesia and iron; it is so son as to lose its polish unless carefully used. It varies in color from a pale-green to a bottle-green. It is supposed that its name was derived from Topazos, an island in the Red Sea where these stones were procured.Also see definition of "Topaz" in Word Study