Strong's G5472 — χαλκηδών (noun)
chalkedon (khal-kay-down') n.
1. copper-like, i.e. "chalcedony"
[from G5475 and perhaps G1491]
KJV: chalcedony 
Root(s): G5475, G1491 
Hebrew root: εἶδος
Occurrences: 1