jasper & feathering

I John saw. I testify
to rainbow feathers, to the span of heaven

and walls of colour,
the colonnades of jasper [...]
--from Trilogy, H.D. 1944

And the building of the wall of it was of pure jasper: and the city was pure gold, like unto clear glass.
--from The Bible, Revelations Chapter XII, "The heavenly Jerusalem, with a full description thereof."

A popular etymology of the Greek and Latin name for jasper is reported by Bartolomaus Anglicus, who writes that "in the head of an adder [snake] that hyght Aspis is founde a lytyl stone that is called Jaspis."
--from The Curious Lore of Precious Stones, George Frederick Kunz 1913

Adder, an example of specialization in meaning, no longer refers to just any serpent or snake, as it once did, but now denotes only specific kinds of snakes. Adder also illustrates a process known as false splitting, or juncture loss: the word came from Old English nǣdre and kept its n into the Middle English period, but later during that stage of the language people started analyzing the phrase a naddre as an addre—the false splitting that has given us adder.
--American Heritage Dictionary

Quetzalcoatl: plumed serpent god of the Toltecs and Aztecs, 1578, from Nahuatl quetzalli "tailfeather" + coatl "snake."

read: "Strange Rumblings at the Center of Our Galaxy"