Green is also the color of vaporized copper.
The Containment vessel for the Trinity Site Implosion device was copper, hence the green glass created from fused sand near Alamogordo, NM.
Trinitite. http://www.tweak3d.net/forums/imagehosting/444987aaa0aa663.jpg
True that, but there are multiple sites on earth where air burst meteors dumped enough energy into the atmosphere to melt desert sand the resulting glass is usually green, as are many fulgerites.
Also any city has abundant copper conveniently suspended up in the air for easy vaporization.
Nice to know about the copper at Alamogordo, though, thanks!