Strong's Greek #271
ἀμέθυστος

Englishman's Concordance (References)

ἀμέθυστος amethystos — 1 Occurrence

Revelation 21:20 - N-NFS
GRK:ὁ δωδέκατος ἀμέθυστος
NAS: jacinth; the twelfth, amethyst.
KJV: a jacinth; the twelfth, an amethyst.
INT: the twelfth amethyst