LSJ
ου, ἡ, either fine brass, brass of Lebanon, or yellow frankincense, Apoc. 1.15, 2.18.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
TBESG
χαλκο-λίβανον, -ου, τό
chalcolibanus, probably 'a mixed metal of great brilliance' (Swete): Rev.1:15 2:18 (RV, burnished brass).†
(AS)
Translators Brief lexicon of Extended Strongs for Greek based on Abbot-Smith, A Manual Greek Lexicon of the New Testament (1922) (=AS), with corrections and adapted by Tyndale Scholars