Dictionary entry

ἴασπις

G. Abbott-Smith's A Manual Greek Lexicon of the New Testament

ἴασπις, -ιδος, ἡ,

[in LXX: Ex 28:18 36:18 (39:11) (יַהֲלֹם), Is 54:12 (כַּדְכֹּד), Ez 28:13 (יָשְׁפֵה, v. BDB, Lex., s.v.)*;]

jasper, apparently not the modern stone of that name, but a translucent stone (DB, s.v.): Re 4:3 21:11, 18, 19.†