LOS is the workhorse patina for metal clay. It can give a lovely aged appearance to silver. It can, with the addition of ammonia and salt, give lovely colors to silver. It can age bronze. However, when applied to copper, it gives … black. There is nothing wrong with black. However, Baldwin’s Patina (available at https://www.riogrande.com/Product/baldwins-patina/335020) provides an alternative. Baldwin’s Patina (hereafter BP) gives copper a blue-green-brown look otherwise unavailable with decades of aging. I am going to describe a project done with BP.
A fiber artist (mostly a knitter, but someone who also spins wool) wanted a sheep pendant. Once I determined that she wanted a cute, cartoon sheep (as opposed to a real one), I was ready to go.
I sketched a cartoon sheep and sculpted it from Art Clay Copper. At this stage, the eyes were just pits — that gets fixed later. The sheep was formed on a tap light dome so it would have some curvature.
Next came refining the sheep. The eyes were made by creating two tiny sphere and placing them in the pits. The eyes were finished by making eyelids of tiny ropes of copper clay and putting them in place. The wool, mouth, ears, and hooves were shaped used standard clay shaping methods.
I placed the sheep on a backing and attached a bail.
Then the piece was ready to fire. Sculptural pieces tend to take longer to fire. I usually ramp at a rate of around 900 d F/hour to 1800 d F, and then leave in the kiln for two hours. I tried using coal, instead of the usual coconut charcoal, hoping for a nice heat patina. It didn’t happen — sometimes it does and sometimes it doesn’t. Then I tumbled the piece for two hours.
Now came the patina. BP only works when it is warm. I placed the piece on a mug warmer and left it about 20 minutes. Then, using a cotton swab, I covered it with BP. Then I waited. The effect of BP is almost magic. First there is nothing. Then, all at once, the color changes. After that, it is a matter of polishing off the patina that you don’t want (I knew the end recipient wanted a light patina, so I rubbed most of it off). I attached a chain, and the piece was done. The coin is for scale.
BP is just another tool in your toolbox. If you want your copper to turn black, there is good old LOS. If you want an intriguing blue-green-brown color, BP is an option you should consider.