Fine silver is great. It doesn’t tarnish. It is, in metal clay form, easy to work with. However, it is also fairly soft. While a fine silver ring is good for a ring that is to be worn occasionally, there are problems with wearing it every day. It will probably slip out of being truly round (easy to fix if you are wearing it yourself, not so much if you have sold it to a customer). Even worse, it can, after lots of wear, acquire dings or scratches. The solution? Sterling.
Sterling silver is a silver/copper alloy. It is about 60% harder than fine silver. While it will tarnish, removing tarnish isn’t hard. In fact, if you own any sterling silver eating utensils, you have probably had to deal with tarnish.
There are several ways of approaching sterling with metal clay. There are sterling clays. However, most require firing in carbon. If you are used to working with base metals, this is not an issue. However, many people prefer the simplicity of fine silver’s open shelf firing. One can create a 50/50 mix of sterling clay and fine silver clay. This approach allows you to open-shelf fire. However, (1) some people find mixing a hassle and (2) this produces an alloy that is close to but not quite sterling, and therefore could introduce legal issues if you sell your work.
Art Clay 950 clay addresses these issues. This clay come premixed. It can be open shelf fired, and therefore avoids carbon firing for those who prefer avoiding carbon.
Art Clay 950 has a texture and feel very similar to Art Clay fine silver. Thus, if you are used to Art Clay fine silver, you will feel comfortable with Art Clay 950. It is not sticky, and has a good working time.
My endorsement is not 100% positive. There were two minor drawbacks. First of all, the firing is two stage. The first firing burns off the binder and the second sinters the clay. This is a minor issue for those used to two-stage clays, like many bronzes are. However, for someone used to working with silver clay only, it could be an issue. The second is that it did not shrink quite as much as Art Clay silver. I used it to make three rings (illustrations below), sized the same as I would have with Art Clay fine silver. The three rings all wound up about a half size larger than I expected. This is a minor issue, because now I know to make future rings a half size smaller. Still, it was somewhat annoying to produce three rings that didn’t quite fit.
The products I used Art Clay 950 for:
The dark blue stone is lapis and the purple stone is tanzanite. These were set with bezel cups. The orange stone is a CZ that I fired directly in the clay.
Overall, I was happy with Art Clay 950. It’s just that, the next time I use it, I will be aware of how much shrinkage to expect.