In Revelation 21:18, the City of New Jerusalem is here said to be pure gold, like pure glass, because gold signifies the good of love from the Lord, and like pure glass signifies transparent from divine wisdom. Because the latter appears in heaven as light, and flows from the Lord as a sun, being like clear glass signifies flowing in together with light out of heaven from the Lord. See Sea of Glass.

(Odkazy: Apocalypse Revealed 912)