Sard, or SARD, a variety of quartz, differing from carnelian only in its very deep red colour, blood-red by transmitted light. It is rare, and brings a much higher price than common carnelian. The name is probably from Sardis. The Sardonyx is an Onyx (q.v.) containing layers of sard.
Sard
Chambers's Encyclopaedia, Volume 9: Bound to Swansea, p. 162–163
Source scan(s): p. 0173, p. 0174