I purchased a product several years ago that gives a wide range of
color to metal. It’s a non-fired, spray or paint on product that
gives a semi-opaque color over the metal, some colors are iridescent,
some metallic and there is an extender to make the colors thinner. I
think the company is still producing these colors (I called and their
message is still on), the address is A & C Distributors; 4311 Coronado
Ave.; San Diego, CA 92107 (800) 995-9946. If you call the number and
leave your name and address they will send you a brochure showing the
colors.
Donna in VA