Cannot disagree with any of that. Nice job with descriptions. But I am talking about true patina. I have a recently acquired razor that has no rust, no pitting, so discoloration, just a kind of dull finish. It is a Crown Razor Co. and I know they stopped producing razors about 1930. It is just a dull colored metal, which I see as patina. So I've considered shining it up to a mirror finish. But I kind of like the patina.