Presently God"s people were wretched, but they would be redeemed. They were bereft of support, without stability, and in despair, all of which God in His compassion noted. They would enjoy richness, abundance, completeness, and variety. Antimony was a black powder that masons added to mortar that held stones in place. It set off the beauty of the stones by providing a dark edging for them. Women also used this powder as mascara to color their eyes (cf. 2 Kings 9:30). Foundations of sapphires (lapis lazuli, a prized dark blue stone) would be foundations of the highest quality and greatest beauty. The battlements Isaiah saw were bright red rubies. The gates were clear crystal, and the walls were a mosaic of other precious stones. This description recalls the picture of the New Jerusalem in Revelation 21:9 to Revelation 22:5. Is that just a poetic description of an ideal city, like this one, or is it a literal description of a specific city? Probably it, too, is a poetic description of the ideal residence of the redeemed throughout eternity, but the New Jerusalem is nonetheless a real place (cf. John 14:1-2). This picture, of wealth, stability, and confidence, contrasts strongly with the conditions of poverty, insecurity, and despair in Isaiah 54:11. The key is God, who will effect the change: "I will."[source]