I’ve been casting sterling silver for so many years now I can’t even remember when I started. Yes I’m getting older). Well I had a customer ask if I could cast in Argentium® 940 PRO Silver. I said I would look into it. So I did. So let me explain the differences
925 sterling silver is the common silver you and I know that has been around for a very long time. It’s 925 parts silver mixed with 75 parts cooper. That’s at least the most basic alloy used and what makes up sterling silver out of 1000 parts.
So Argentium® 940 PRO Silver is 940 parts silver (94%) 50 parts cooper (5%) and 10 parts germanium (1%). That higher silver content and the added germanium really makes a big difference in keeping the silver tarnish resistant.
Now getting back to the customer that asked if I could cast one of my rings in Argentium® 940 PRO Silver. I do loose out by jumping into a new area such as this. I have to buy much more silver than just the ring because casting silver requires a large button and silver sprues that go to the ring. I’ve never done it with this type of silver so there is the “I’m a bit afraid” factor. I do like to learn new things so I thought I should try it. I invested into it knowing that I may or may not ever do it again.
So my first impressions on casting with it. It took longer to heat up than 925 silver so a little more time is involved and gas from the torch. The surface was so clean when all the way melted. It seamed a little more sluggish than sterling. When I would pull the torch away for just a second to see the surface it was different than with 925. With 925 the oxidation comes and the surface skin comes quickly and that’s why the boric acid helps keep the surface clean. With Argentium® 940 PRO Silver the surface never would get that oxidized surface. It just stayed shinny and bright with no skin. The hard part about casting it is that I usually have visual markers for sterling silver for when it’s hot enough. With 940 silver all those visual clues were not there. I didn’t want to under heat it or overheat it. All I could do was my best and that was to just use my best judgement. So that is what I did and it worked. Yes, I was so excited. Usually with sterling silver the casted pieces are oxidized black. With the 940 silver there was no oxidation and it was all looking like silver. I was impressed. This image shows what it looks like right after casting and the investment is cleaned off it.
Argentium® 940 PRO Silver casting
Cleaning up the silver was also a new experience. I noticed it was a bit brighter and it was just a neat experience. When it came time for the oxidation I was not sure how difficult it would be. I thought it might be really hard to do. I used Winox and had to heat up the silver to make it work. The heat did the trick and I got it oxidized very well. In the end it turned out very nice and I could be more happy with it.
Casting with 940 silver is much more expensive. It takes longer to heat up, more gas is used and so the whole process gets a little more involved. I took this experience as paid schooling so that I could become a better all around jeweler with more knowledge and experience. I’m not sure I’m ready to add this alloy to my line of jewelry just yet, but I would consider it. If you have any thoughts or would love to see it more often in my work then leave a comment below and let me know. I hope this was helpful to anyone looking into using different silver alloys. It was a fun experience and I did enjoy it.