Jacinth

Jacinth (hyacinth) is a precious stone of deep reddish-blue or violet color appearing in the book of Revelation. It is listed as the eleventh foundation stone of the New Jerusalem (Rev. 21:20) and appears in the description of the locust-horsemen: "breastplates of fire, and of jacinth, and brimstone" (Rev. 9:17), where the color is part of a terrifying vision. The Hebrew word leshem in Exodus 28:19 (the ninth stone of the high priest's breastplate) may correspond to jacinth or to the amber-orange topaz, but exact identification is uncertain due to the imprecision of ancient gem nomenclature. The stone was prized in antiquity for its transparency and deep color.