Revelation 4:3 The One seated there looked like jasper and carnelian, and a rainbow that gleamed like an emerald encircled the throne.
The darker the shade of green in an emerald, the more valuable it is. Shaded or lighter colored emeralds are usually referred to as beryl, not emerald.
We are used to seeing cut emeralds,
but imagine, if you will, an emerald rainbow. Many Christian artists have attempted this, some known (Botticelli, Dore, Chagall), most unknown.
but imagine, if you will, an emerald rainbow. Many Christian artists have attempted this, some known (Botticelli, Dore, Chagall), most unknown.
Ezekiel 1:28
The appearance of the brilliant light all around Him was like that of a rainbow in a cloud on a rainy day. This was the appearance of the likeness of the glory of The LORD. And when I saw it, I fell facedown and heard a voice speaking.
The closer we get to the living presence of God, the deeper our walk, the stronger our covenanted relationship is with Him. The emerald rainbow surrounding God's throne is reminiscent of the covenant He instituted in Genesis 9:12-16, in which He created a rainbow and set it in the first heaven: the sky and the clouds. 
The emerald is the fourth stone in the ephod of the priestly garment. While there is much conjecture as to which tribe it represents, the Bible states that the names of the sons of Jacob are engraved on each in the order of their birth, read from right to left. Therefore, emerald represents the tribe of Naphtali, Jacob's fourth son. Also, in Revelation 21:19, the fourth foundation of the new Jerusalem's walls is covered in emeralds.
Psalm 52:8 But I am like a green olive tree in the house of God: I trust in the mercy of God for ever and ever. Here emerald green testifies of trust in God's mercy because I have made God my Refuge, not material wealth and possessions (verse 7). Emerald green here is Abundant Living through Faith in God; a deep, expansive life in The Tree of Life: Jesus Christ.
