Sorry Peter- All surface treatments are just that. Most are just
molecules thick. They all will wear away. Especially on rings.
Gold platinum and palladium are all precious or noble metals and are
desired because they don’t succumb to oxidation and acids.
The lovely and very talented Sarah Graham uses a ferrous metal for
her black accents. It takes high tech machinery to cast and has to be
mechanically attached to the gold parts of her work. A very cool
If you want true black jewelry you may want to look into the newer
ceramics that Etienne Perret is using for his work. It’s very
handsome and dramatic.
Have fun and make lots of jewelry.