This verse continues without a stop from verse 2. The portrayal of the invisible God is in terms of similarity with light and colors, without any attempt at a physical description.

He who sat there appeared like jasper and carnelian: the important thing about the semiprecious stones jasper and carnelian is their color, not their consistency, shape, or size. Beckwith comments: “the language is meant to express merely the splendor of the light in which the prophet beholds God manifested and encircled.” The Greek “had the appearance of jasper and carnelian” means “(he who sat there) shone with a light the color of jasper and carnelian.” So New American Bible, Revised “whose appearance sparkled like”; Phillips “His appearance blazed like”; Bible en français courant “he had the resplendent brilliance of.” Good News Translation “His face (gleamed)” is too specific and should not be imitated by translators, since in biblical literature no mortal sees the face of God.

There is no complete certainty about all the stones that appear in Revelation. The semiprecious jasper may be yellow, brown, red, or green; it is actually somewhat dull and opaque. Some commentators suggest that the writer had in mind an opal; others, a diamond. The same holds true for the carnelian, which is usually red. New Jerusalem Bible translates “a diamond and a ruby.” If the specific names for the stones are not available, a translation can say “a green and red light, like the colors of some precious stones.” But in areas where semiprecious stones are unknown, one may simply say “He shone (or, glowed) with a beautiful green and red light” or “His appearance shone (or, glowed)….”

And round the throne was a rainbow that looked like an emerald: the language seems to indicate that the rainbow formed a complete horizontal circle around the throne, something like a halo (which An American Translation and Phillips say). Less probable is the possibility that the rainbow formed an arch over the throne. The important thing in the comparison with the emerald, a green-colored precious stone, is not the color (a green rainbow would be a strange sight indeed, even in a vision) but its brilliance. So a translation will do well to translate “that shone like an emerald” (Bible en français courant, Nova Tradução na Linguagem de Hoje), “gleaming like an emerald” (Barclay), or “bright as an emerald” (Revised English Bible). Again, as in the case of jaspers and carnelians above, if precious stones are unknown, a translator may say, for example, “there was a rainbow that gleamed brightly.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on The Revelation to John. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .