Sardius

·noun A precious stone, probably a carnelian, one of which was set in Aaron's breastplate.

sardius
sardĭus, a, um, adj. [cf. 1. sarda, II.], sardian , carnelian (late Lat.): lapis, Vulg. Exod. 28...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.