How can I get this finish?

[dhickson]

Hi - I'm new to this forum so please let me know if I'm posting this in the right place. I am attempting to restore an antique clock that has feet and other parts cast from what I think is pot metal. They seem to have some kind of blued or blackened finish that I hope to duplicate. They do not seem to be painted. The finish has an almost black color, but with a green tinge and other colors (oil-slick-like shimmer) in some places, such as the underside. I'm attaching a couple photos (if I can figure out how to do it!) that show the original part, plus a new cast part that I hope to use if I can't find an original replacement. Thanks in advance for any help you can provide.

[cprocess]

More than likely, this part has been copper plated, then cupric oxided for the black/green finish. The part can then be tumbled to give more of a contrast between the raised areas versus the low recessed areas. The part is then waxed, oiled, or lacquered to protect the oxide.