All materials are unanodized Niobium from The Ring Lord. Rings are 18 gauge, WD 1.2 mm, ID 5.6 mm, AR 4.67. The S hook is hand forged from 16 gauge wire following Scott David Plumlee's book: Handcrafting Chain and Bead Jewelry. I read this book back to back more times than I can remember, a must-have!!
Since I have an anodizer sitting in my garage, will give it a try in coloring some Nb rings; this should be fun:-)