Good results with Electroetching

At the request of a student, we are exploring electroetching in my
advanced class. We did copper and brass today, using salt water with
the titanium anodizer as the power source (2-3 amps, 12 volts). It
worked pretty well.

My research on line turned up the suggestion to use copper sulfate
to electroetch copper. I am not sure this is an improvement on ferric
chloride in terms of toxicity-- can the chemists among us enlighten
me? Is it likely to be a good choice? I wouldn’t think it would make
sense to etch with an electrolyte that already contains copper.

If that would, in fact, work, would old pickle be a good
electrolyte? I can try it, of course, I just ran out of time in class
today.

Experiments on silver were not promising. I know we’ve discussed
this here before. Has anyone gotten good results on silver since the
last discussion?

Noel