These beautiful sterling silver shakudo Mokume Gane Tungsten Rings are made from high grade cobalt-free Tungsten Carbide. Mokume Gane is an ancient metalworking technique that layers different metals together to produce one of a kind designs. This ring is available in 6 mm or 8 mm wide and can be worn as a Wedding Band or Promise Ring. Larson Jewelers is proud to present our Tungsten Carbide Ring line. Tungsten Carbide is the newest and strongest metal to be used in jewelry, ideal for men and women who are tired of rings that scratch easily. Truly Free Lifetime Sizing and Lifetime Warranty on all tungsten rings, no exchange|sizing fees, which are charged by our competitors.