Argentium® Sterling Silver is a relatively new silver alloy, patented by Peter Johns in 1996, which combines 92.5% pure silver with the metals of germanium and copper. The substitution of some copper with germanium allows this silver to be highly tarnish-resistant, heat-hardened at a lower temperature in your home oven, and most impressively allows the metal to be soldered without the darkening fire-scale effect. In my humble opinion, Argentium® is truly the way sterling silver was meant to be.
Despite its tarnish-resistance, your jewelry may darken with time, humidity and your bodies Ph balance by the chemical process of oxidation. However, this oxidation/tarnish is only on the surface of the metal and can be cleaned by scrubbing with baking soda/toothpaste, an ultrasonic cleaner, or by using a chemical silver cleaner to remove the oxidation. I utilize a rock-tumbler with stainless steel-shot to produce a bling-bling shine.
<- As seen at left, I stamp my clasps with A925 to indicate it is Argentium.