Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

In article <opr7wfrpnoooawdc@...>,
Stefan Trethan <stefan_trethan@...> wrote:

> > I found something at an art store a few years ago called "Liver of
> > Sulphur" which I used to blacken copper for antiquing purposes.

Pottasium Sulphide

Stuart.