Crystals
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Revelation 21:11
shining with the glory of God. Its radiance was like a most precious jewel, like a jasper, as clear as crystal.
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
Ezekiel 1:22
Spread out above the heads of the living creatures was the likeness of an awesome expanse, gleaming like crystal.
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.