Sardine stone
Easton’s Bible Dictionary & Webster’s 1828 Dictionary · Matthew George Easton, Noah Webster
Sardine stone - (Easton's Bible Dictionary)
(Rev. 4:3, R.V., "sardius;" Heb. odhem; LXX., Gr. sardion, from a root meaning "red"), a gem of a blood-red colour. It was called "sardius" because obtained from Sardis in Lydia. It is enumerated among the precious stones in the high priest's breastplate (Ex. 28:17; 39:10). It is our red carnelian.
Source of the article
Matthew George Easton, Easton’s Bible Dictionary; Noah Webster, American Dictionary of the English Language (1828)
Bible Strong combined digital edition