Excerpt from Kurt Nassau's book Gemstone Enhancement;
"Irradiation will turn colorless or pale colors of quartz to smokey
or greenish yellowl" Oro Verde
"Heat will turn smokey to paler to greenish yellow to green,
"Heat will turn Amethyst to yellow [many shades including lemon
yellow], colorless or green" greened Amethyst.
Rough reaction will depend on mine rough comes from and inclusions
(chemicals) in rough quartz.
Hope this helps