Meaning of CRYSTAL in English
the representative in the Authorized Version of two Hebrew words.
â Zecucith occurs only in (Job 28:17) where "glass" probably is intended.
â kerach occurs in numerous passages in the Old Testament to denote "ice," "frost," etc.; but once only (Ezekiel 1:22) as is generally understood, to signify "crystal." The ancients supposed rock-crystal to be merely ice congealed by intense cold. The similarity of appearance between ice and crystal caused no doubt the identity of the terms to express these substances. The Greek word occurs in (Revelation 4:6; 21:1) It may mean either "ice" or "crystal."
Smith's Bible English dictionary. Английский библейский словарь Смита. 2012