HYACINTH

hi'-a-sinth (huakinthos): the Revised Version (British and American) uses this word in Revelation 9:17 for the King James Version "jacinth," with reference, not to stone, but to dark-purple color. In Revelation 21:20, where stone is meant, the Revised Version (British and American) translations "sapphire."

From the International Standard Bible Encyclopedia
Edited by James Orr, published in 1939 by Wm. B. Eerdmans Publishing Co.