I figured it out- at first I was trying to oxidize and enamel over but that did not keep the letters cleanly dark. I remembered finally that I filled in the letters with the half Distilled half binder liquid with a tooth pick and sifted enamel over that. Fire, score, then fire transparent over that at a super high temp. Thanks for the help!

I stamped and enameled this copper cuff bracelet over a year ago and did not take notes while doing so. the same client wants a repeat.... Crap! I've already ruined some things trying to get the same look again... Someone please, help!
I can tell you that I tend to run super hot, so I know that this green affect is caused by over firing or burning the piece, on purpose. I cant remember how I got the letters to stay black when I fire transparent enamel over it.