Hey guys I am putting together a project with 4 items that I want to have a different metallic "color".

So far I have made the objects in sterling silver, tin-bronze, and a 98% copper alloy.

In your guys' experience, which easily castable white alloy differs the most in appearance from sterling silver when polished? I am looking for a more deep gray/metal appearance than the "white" you get from sterling.

I suppose any such alloy will eventually look different due to the slight yellowing of the sterling, but I am hoping to have a difference very apparent when freshly polished.

Currently I am leaning toward a zinc-aluminum alloy.

I would greatly appreciate your ideas!