Revelation 4:6
Also in front of the throne there was something like a sea of glass as clear as crystal. Around the throne, at the middle of each side were four living creatures dotted with eyes in front and behind,
Revelation 4:3
The One who was seated on it looked like jasper or sardius, and around the throne there was a rainbow that looked like an emerald.
Revelation 21:11
and it continued to retain the glory of God. The luster of it was like a very precious stone, like jasper, clear as crystal.
Treasury of Scripture Knowledge
Summary
And the likeness of the firmament upon the heads of the living creature was as the colour of the terrible crystal, stretched forth over their heads above.
The likeness
Bible References
The likeness
Revelation 4:3
The One who was seated on it looked like jasper or sardius, and around the throne there was a rainbow that looked like an emerald.
Revelation 21:11
and it continued to retain the glory of God. The luster of it was like a very precious stone, like jasper, clear as crystal.