After my Art Clay Copper experiments (see New Art Clay Copper Experiment and Copper ArtClay Disaster!), I decided to try a different brand of metal clay for copper and bronze pendants. I ordered some of the Prometheus clay made in Turkey (usually referred to as Pro clay), instead of the other brands, simply because it fires quicker and seemed easier to deal with. I was not disappointed at all! The fresh clay was a pleasure to work with, as it is so soft and moist, and very manageable. After they dried, some of the pieces looked like this:
So I wrapped them in paper towels and then bundled them up in fiber blanket to get them ready to be fired in the kiln:
I am not too fond of fiber blanket, but I wanted to try this quick method to see how hard the bronze would come out and how much oxidation it would prevent. Most of the bundles were tight, but I left a lose end on a couple of them (to measure oxidation if I fire them without the blanket). Once fired, the bronze pieces came out wonderfully hard, with a somewhat copper-ish color. As expected, the ones that had more air exposure had more oxidation than the ones completely wrapped in the paper towels and fiber blanket, but nothing excessive, which was pretty nice to see. Below are the pieces after being tumbled. You can still see the copper-ish hue they have (sorry for the bad photo, it was a very quick one with bad light).
I brushed them with a brass brush and the color changed to more of a usual bronze tone:
I love the feel of these pieces! They’re like little jewelry sculptures… I chose a blue and green patina to finish these designs:
I will have better pictures of these for the web site’s Jewelry Shop once I make bronze chains for them, and I will also share more experiments with the new Prometheus copper clay soon. Stay tuned…
Hi, Your article is the best about firing Prometheus bronze. Do I get this right? You wrap dry pieces in paper towels then fiber blanket, and set them on the kiln shelf…or does it still have to go into a container with carbon??? I want simple & quick, so I”ve stayed away from the bronze/copper up until now. Also what degree do you fire it? I agree with your sacred approach to the work. Thanks for any input. Also, know that the Rio people refer to “Pro” as their lower grade but stronger “silver” new clay. I’d rather tell my buyers it’s 999 pure fine silver. Thanks again. Pat
Hi Pat,
Thanks for your comment. Yes, you wrap the dry pieces in paper towels and fiber blanket, and set them on the kiln shelf. No need for carbon. You can place some carbon inside the paper towel, if you like the piece to come out with less reddish, copper looking hues (and more traditional yellowish, bronze hues), but you don’t need to place the fiber blanket in carbon. In fact, the paper towels and fiber blanket act as carbon would otherwise, to prevent oxygen from entering in contact with the bronze and creating oxidation. I fire at 1472 degrees for 30 minutes.
You know, I didn’t think about the new “pro” silver clay when I wrote this post. Oh well, at least I made clear I was referring to bronze clay! 😉
Thank you , Yol. This is a great explanation and encourages me to actually try it. Your work is beautiful.
Thank you! You should definitely try it. The Prometheus clay has such a smooth, manageable texture that it’s a pleasure to work with it. Just make sure you wrap your piece very well with the towel and the fiber blanket. Any air getting in will create oxidation. Have fun!
Hello Yol… I stumbled upon your blog, and am delighted to see your work. After a couple of disasters, I have had some success torch-firing Prometheus bronze clay. I wish the color was more golden, but one piece that I made has taken on a gold tinge with time: very interesting.
I love your patinaed pieces. may I ask how you achieved the beautiful colors?
Kind regards,
Sulie
Vienna, Austria
Hi Sulie,
Thank you for your comment. I use water based patinas for base metals from Townsend Atelier. You can probably find something similar in your country; sculptors use them to finish their work. You can mix them up and create the colors you want; I apply the ones I use to heated surfaces, but there is a great variety of patinas (acid and non-acid, reactive and non-reactive, UV safe, etc.) in many colors. Good luck experimenting with metal clay and keep up the good work!