Topaz
Archimandrite Nikifor’s Biblical Encyclopedia
(Exod. 28:17)—one of the precious stones set in the high priest’s breastpiece. The Hebrew term pitdah is traditionally rendered topaz, though ancient color terminology and mineral names do not correspond neatly to modern classification; chrysolite or olivine has also been proposed. The stone was associated in antiquity with the Red Sea region, but the source’s precise etymology and commercial anecdotes are not secure.