I cast mine and my wife’s out of F-75, which is a medical grade cobalt alloy, Co-26Cr-6Mo. I had a jeweler make the ring waxes, a company in Michigan make the investment cast mold, then I poured it at work and did the finishing. Made three rings for me and three for the wife. Finished one each as high polish, blacked, and rock finish, though we both agree the rock finish is the best. I typically wear mine on a chain to keep from damaging it at work.
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