κρύσταλλος krýstallos

Meaning

ice, i.e. (by analogy) rock "crystal"

In the King James Version: crystal

Derivation: from a derivative of (frost);

Where it is used

• Revelation 4:6 And before the throne was something like a sea of glass, as clear as crystal. In the center, around the throne, were four living creatures, covered with eyes in front and back.
• Revelation 22:1 Then the angel showed me a river of the water of life, as clear as crystal, flowing from the throne of God and of the Lamb