Revelation 4:6
also in front of the throne there is like a sea of glass, resembling crystal. And on each side of the throne, all round it, four living Creatures full of eyes inside and outside;
Revelation 21:11
with the glory of God. The sheen of it resembled some rare jewel 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 21:11
with the glory of God. The sheen of it resembled some rare jewel like jasper, clear as crystal;