Argentium Silver
Filed in archive jewelry techniques by Maggie MacLean on March 06, 2008
Argentium® Sterling Silver
By definition, sterling silver has 92.5% pure silver and 7.5% other materials. Pure silver (fine silver) is rather soft, so adding another metal helps make sterling silver sturdier so it holds up to regular wear. Silver is typically alloyed with copper, which makes a durable and attractive blend, but it tarnishes easily.
Argentium has the same 92.5% silver, but it also has a little bit of a metal called Germanium, which makes it far more tarnish resistant than .925 sterling silver.

Working with Argentium
Argentium is more ductile (able to stretch) and malleable (able to bend without breaking) than Sterling Silver. Before using Argentium wire, you can heat it slightly to engage the tarnish resistance, and this may harden it a little as well, and make it a little easier to work with.
The Tarnish
Sterling silver tarnishes due to the presence of sulfur, which reacts with the copper. Sulfur can come from perfume, deodorant, skin, and the atmosphere. Some people tend to tarnish silver quite rapidly.
So why doesn't Argentium tarnish like sterling silver? The difference is that small amount of Germanium. 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 the protective layer faster. This is also why it's not necessary to protect Argentium from oxygen when soldering or fusing.
When Argentium does tarnish, it takes on a very soft yellow color, where .925 sterling silver forms a dark black patina. Under normal circumstances, washing with dish washing liquid and a soft brush is all that is required to keep Argentium sterling silver jewelry bright and shiny.
Just last year, beads, chains, and clasps in Argentium became available. I think it's worth the small extra expense for its strength, beauty, and its tarnish-resistant finish.
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About Argentium Silver
Labels: Argentium, Silver Jewelry, Tarnish