Hello !
Just found some material at:
http://www.mauigateway.com/~donjusko...ranslucida.htm
Very interesting stuff! But he said nothing about details. I know brass is a mix from copper and something other
but surface (porousity etc.) is the same.
I hope those technique-genius-guys (Marvin M. & Michael G. etc.) have had some experience with this.
Sincerely.