sardius(n = noun.substance) sard, sardine - a deep orange-red variety of chalcedony;
is a kind of calcedony, chalcedony
A precious stone, probably a carnelian, one of which was set in Aaron's breastplate. Ex. xxviii. 17. [1913 Webster]
sardius, n. Bibl. etc. a precious stone.
Etymology:
ME f. LL f. Gk sardios sard