At MGS, we regularly test the silver fineness of flatware sets, jewelry, and other items. As with all precious metals, there are different purity levels for different reasons. Sometimes impurities are naturally occurring, and other times they are added to create an alloy with new aesthetics or “features” that pure precious metal doesn’t have. Of particular interest is Argentium sterling silver.
The alloy (patented in the early ‘90s by Argentium Silver Company, UK) is just like normal sterling silver except for one small difference. While sterling silver is about 92.5% silver and 7.5% copper, Argentium sterling silver replaces a small amount of the copper (about 1.2%) with an element called germanium. Even though the amount of germanium is small, the difference is big. By adding germanium, sterling silver develops several beneficial new properties, including:
• Firestain / Firescale elimination
• Better tarnish resistance
• Precipitation hardening / heat-hardening properties
• Increased ductility
• Increased thermal and electrical resistance
The addition of germanium can benefit other silver alloys as well. For example, another alloy called Argentium Silver 960 is just like Britannia Silver in terms of silver purity. But, some of the copper is replaced with germanium.
Argentium sterling silver and Argentium Silver 960 provide a number of advantages for both jewelry designers and metal refiners – most notably the elimination of firescale. In our next blog post, we’ll discuss the problems firescale creates and how germanium/silver alloys like the Argentium series eliminate it.