18g AWG square Argentium silver.
Where traditional sterling is mixed with copper, Argentium is mixed with some Germanium. This makes it very resistant to both fire scale and tarnishing. It costs a bit more, but well worth it. As with all of our rings, these are saw cut, then tumbled to a mirror finish.
Actual wire diameter: .040" x .040", 1mm x 1mm
Approx rings per troy ounce