My last experiment combining copper and bronze clay didn't go very well, but I tried again and this time I had success! And I learned some things along the way.
First, I'll share a piece that's just bronze clay. When I take them out of the kiln, they have some fire scale and are a pinkish color. I have been polishing them with my flex shaft and some 3M Radial Disks. I decided to leave a bit of the pinkish color in the texture on this piece.
These pieces are to be earrings for myself. I wanted to make something that had all three metals I've been using, so I used one of my favorite textures (a shell with worm holes in it) and cut circles of the same size. I wanted to show the difference in shrinkage of the clays. It's kind of hard to see here, but the copper is considerably smaller. BronzClay only shrinks about 10 percent while CopprClay shrinks 15 to 20 percent. I had misread and thought they both shrunk only 10 percent, which may have been part of the problem in my last firing.
This piece is all bronze, but it I wanted to show what happened to it. I had it sitting on top of the plaid flower pendant I showed in my last post and it picked up a cool orangy patina. I decided to polish off the dragonfly and leave the rest. The picture doesn't show that there are some blues in the patina, too. I will apply a lacquer to preserve this patina.
Here is another version of the dragonfly pendant, which is made with a mold I got at Cool Tools. Here is my first bronze/copper combination. I filled the dragonfly depressions in the mold with copper and let it dry. It took a while to clean up around the dragonfly so there was no other copper in the mold. I then pressed in a thick slab of copper clay and let that dry. It came out pretty good, I think, except for a couple of cracks in the wings. You can see the difference in the colors fairly well in this photo.
This next set is to be a necklace, bracelet and earrings. It's hard to see the color difference, but it's there. Here I made bronze pieces with this design that is vaguely Japanese to me. I let those dry and then pressed them into thick slabs of copper clay and cut out frames. When I made these, I still thought that copper and bronze shrunk at the same rate. Another bit of serendipity here: The copper shrunk more, but instead of cracking, it domed the pieces, something that's a bit hard to see here.
I had some bits of both clays left and decided to see what would happen if I combined them. I made a flat piece of each, put one on top of the other, rolled them up, sliced the rolls and rolled out the pieces. It gave the clay a Mokume Gane kind of look. It worked and does show up on the fired pieces, except not as much as I would have liked, so I patinaed them with Baldwin's Patina, so the copper shows up a bit more. I will try this technique again now that I know a bit more about it and that it works. One of the keys is not to mix the clays too much or you lose the marbling.
Lastly, I will leave you with a photo of the necklace I made with the flower and plaid piece that I turned green with Baldwin's Patina. I was lucky to find these frosted glass beads that matched perfectly.