hi'-a-sinth (huakinthos): the Revised Version (British and American) uses this word in Re 9:17 for the King James Version "jacinth," with reference, not to stone, but to dark-purple color. In Re 21:20, where stone is meant, the Revised Version (British and American) translations "sapphire."
The International Standard Bible Encyclopedia
Hyacinth
The International Standard Bible Encyclopedia, James Orr (1915). Public domain, from the CrossWire SWORD module.