I'm confused. If you heat a metel and let it cool without any interference - annealing? When you heat it and plunge it into an oil bath like a Samuri sword is that heat treating/hardening. Would you anneal or harden a ring? Maybe anneal to remove cast iron's brittleness? Don't know. I know that Frank bowman heats his rings to 1,850 degrees F. What does he do after that?

Bill