Are there any issues with pewter outdoors? I am using a tin/bismuth alloy. I'm guessing that the oxidation issues are more along the lines of patina rather than corrosion. These pieces will be outdoors in weather on the California coast with salt air.

I have done some plaster investment casting, and am trying to figure out how it compares to ceramic shell.

All the discussion I have seen seems to assume a basic understanding of certain facts, which I do not have. So here are a few questions.