Skip to main content
.

About Argentium® Sterling Silver

Introduction to Argentium

Argentium® Sterling Silver is a new blend of Sterling silver invented in 1996. By definition, sterling silver has 92.5% pure silver and 7.5% other materials. Pure silver (known as fine silver) is rather soft, so adding another metal helps make the sterling sturdier so it holds up to regular wear. Typically, sterling is blended with copper, which makes a nice strong and attractive blend, but it tends to tarnish easily. Argentium has the same 92.5% silver, but has a little bit of a metal called Germanium blended with the copper. For chemical reasons, this makes Argentium sterling far more tarnish resistant than standard sterling silver. You'll be amazed at how long it stays bright.

Another benefit of Argentium is that it can be hardened by heating it in an oven. I do this hardening on all of my Argentium silver chain maille jewelry, which will help to guarantee every piece can be handed down as an heirloom.

Argentium looks just like traditional sterling silver, since it is just another form of sterling silver. When tarnished, it takes on a slightly grey tone, where silver tends to form a dark black patina. I have a watch that has 1/2 band in sterling and 1/2 band in Argentium, and unless it's tarnished I can't tell them apart.

Back to top

When I use Argentium

I started working with Argentium silver in mid-2005, and have transitioned to using Argentium as much as possible because I think it's worth the small extra expense for its strength and beauty. Unless traditional sterling silver is specially ordered, I develop all new jewelry using Argentium wire and chain maille rings. Some pieces in my stock were made from standard sterling — I have marked these as "Sterling" in the descriptions.

At this time (mid-2007), though, beads and chains and clasps in Argentium are just starting to be available, and not yet from many suppliers or in many designs. I am still using traditional sterling silver for silver clasps, beads, and those chains that are not hand-made.

Back to top

Why is it tarnish resistant?

Sterling tarnishes due to the presence not of oxygen, which is the usual assumption, but from the presence of sulfur, which reacts with the copper. Sulfur can come from perfume, deodorant, skin, and the atmosphere, especially around swimming pools (chlorine is hard on silver too) and near some work areas. Some people, like myself, tend to tarnish silver we wear quite rapidly.

So why doesn't Argentium tarnish the same way, since it also includes copper? The difference is the small amount of Germanium. Without going into too much technical detail (available elsewhere), Germanium really likes to react with oxygen. It forms a thin layer of Germanium Oxide on the surface of the metal, which is almost transparent. This layer keeps the sulfur from reaching the copper, so it can't react and cause tarnish. While this barrier layer will build up over time at room temperature, heating it will help build this protective layer faster, which is why I heat treat all my Argentium. This is also why it's not necessary, and not even desired, to protect Argentium from oxygen when soldering or fusing. Oxygen + Argentium = good.

Note: if you're just interested in the basics about Argentium don't feel guilty for stopping here!

Back to top

Working with Argentium

Although I have heard some people discuss Argentium as feeling "mushier" than traditional sterling to work in, I haven't noticed the difference at all. Argentium is more ductile (ability to stretch) and malleable (ability to bend without breaking) than Sterling, so perhaps the difference is what each artist is trying to do with it. Before using my Argentium wire I always heat it slightly to engage the tarnish resistance, and this may harden it somewhat and keep it from feeling softer than sterling. I find the wire works beautifully, and depending on the type of finished piece I will treat it as much as possible to raise the tarnish resistance.

I have also had the opportunity to fuse Argentium chain maille rings. I was thrilled at how easy it was to get the rings to fuse closed (it's easier with bigger rings, for reasons I haven't figured out). I have not tried soldering with Argentium, though Argentium solder is available, which should definitely be used so the solder will not discolor too much faster than the rest of the piece. For fusing, I've found that it works best if I wave my torch (I've done this with both a basic BernzOmatic propane torch and a butane micro-torch) over the ring to heat it slightly, then almost immediately put the flame right on the join. I hold it so the tip of the blue flame was less than 1cm away from the join. Within a couple seconds the join will start to glow redder than the rest of the ring. Try it a couple times and you'll figure out how long you can hold it there to ensure it joins solidly — I find it is around 2–4 seconds. The ring gets rather red, but it doesn't melt. I would recommend holding the flame there until you melt one ring, and then you'll know how long is too long. Just do a few joins, and test whether you can open them, and try again if you weren't holding the heat there long enough. All in all, I can fuse a handful of rings (I do single rings, not yet a connected chain) in less than a minute.

I don't use any flux unless I'm balling the ends, because Argentium won't develop firescale and actually loves oxygen (again, for chemical reasons). I do find I needed to pickle the rings to get them back to their original bright finish. Then, after heating and polishing, the joins are almost invisible. For a surface, the recommendation from experts is that you use a new soldering surface and reserve it just for Argentium use. I would recommend against using a charcoal block, because charcoal is used to eliminate oxygen and I noticed it can tend to worsen the blackish coating that has to be pickled off (especially on the side of the ring that is on the charcoal block and away from oxygen).

Back to top

How I treat my Argentium

When I'm working on an Argentium piece with no other stones, such as with my chain maille, I treat it in a number of ways to improve the tarnish resistance and polish it beautifully. Some of these steps I will skip if the item includes stones or other pieces, or other things that can be damaged.

  • Heat treat the Argentium after purchase to 250°F to activate the tarnish resistance, then polish
  • Heat treat the Argentium after finishing the piece to 550°F to harden the metal
  • Pickle away the discoloration from heating, if any
  • Tumble the piece in a rotary tumbler with stainless steel shot
  • Polish the piece with Goddard's Silver Foam

Do you need to do all these steps? Probably not, but I prefer to be certain that my pieces are as tarnish resistant as possible. Here are some details about my processes:

There are 2 types of heat treating with Argentium, as mentioned above. Both are done in a clean oven (to reduce discoloration and buildup) on a clean pyrex dish or pie plate. Don't cover it — remember, Argentium loves oxygen.

The first type of heat treatment is to use a cooler oven, 250°F, for about 10–20 minutes to build up the layer of Germanium Oxide to protect the Argentium from tarnish. I find that this doesn't usually cause any discoloration so it's not necessary to pickle after this step, but I tend to polish the wire when I'm done. I think this may harden it ever so slightly, but that's not something I've read — just my personal experience. Certainly not anywhere near the stage of spring hard. I like doing this to my wire so even if I'm working with delicate stones and can't treat the piece further I still have the tarnish resistant layer in place. Supposedly the suppliers have started doing this step now before shipping the wire, but they weren't when I started working with it and this way I'm certain it's been done.

The second type of heat treatment is to use a very hot oven, about 550°F, for about 1–1.5 hours which will harden the Argentium and make it more sturdy. This should be done only after the piece is entirely finished, as it will make the wire quite hard. Sometimes this does cause a bit of discoloration, but it's easily removed with pickle. Be sure to let the pieces cool before moving them around or putting them in the pickle (or touching them, as I sometimes almost forget and do). Oh — just to be clear — this only works for Argentium. No other metal I know of will harden at kitchen oven temperatures.

Although it's probably not as necessary with Argentium that's been heat hardened, I still run as many pieces as I can through a tumbler with stainless steel shot. For regular sterling silver this can help harden the piece, but I just like how bright and shiny they come out.

I also like Goddard's Silver Foam. Goddard's Long Shine Polish or the Long Shine Cloth have been shown to extend the tarnish resistance of Argentium, but they're very hard to use on chain maille. The foam is wonderful for getting into all the crevices and still washing away well.

NOTE: for each of these steps I'm careful to evaluate whether it's going to be safe for the particular piece I'm working on. If I'm working with stones I'll take one of the poorer quality stones from the strand and test it with the polish, then with the tumbler, and then perhaps in the oven (no stones have made it through the oven yet). I'll only do those steps on the finished item that didn't hurt the test stone. Usually I can at least do a quick sponging with the Silver Foam and a rinse, even if I don't want to risk tumbling or heating.

Back to top

More resources about Argentium

There are some great resources out there about the use and properties of Argentium. These are a few of my favorites:

This information is ©2007 Amy Roos, Kallisté. Do not reproduce or copy this information in any form without contacting me for permission. Thank you.