This technique is done by creating a mask on a sheet of bi-metal (2 thin sheets of different metals or alloys) and then etching the exposed area until the bottom layer of metal is revealed. The same process is used to create circuit boards and was translated and adapted for use on precious metals by Carol Webb of Santa Cruz, CA.

The drawing on the front of this amulet (pictured right) is from copper/fine silver bi-metal. I photocopied and reduced onto a sheet of Press and Peel transfer paper a pencil drawing I had done of a statue of the Pharaoh, Tutankhamun. When heated, the paper transfers the design to the copper side of the metal, which serves as a mask for areas not to be etched. I etched away all the exposed copper using ferric chloride, leaving only the copy of my drawing. After fabricating the amulet, I patinated the copper black to give greater contrast to the face.