Aluminum doesn't scorch. It will burn, but you won't get the pretty discolorations like you do with steel. Mostly it just melts and burns away, assuming a hot enough fire. I've done it with my bunsen burner at work. The results are not pretty.
I recommend holding the emitter over a candle, down into the flame. You'll get a soot buildup that may be the look you're seeking.
Bookmarks