Patina, I believe that is the right term

[http://users.livejournal.com/_delicateterror/]

Hello all!

I'm looking for some help please. I've looked online and can't seem to find any 'do it yourself' ways to turn metal green that don't require crazy chemicals.
I've found out how to age metal or rust it but I was hoping for some green areas.
I could paint the metal in place but I am sure that would require some special paint and I was hoping to use household items that are already kicking around.
The piece in question is a large valve, most likely from a water pump. It's silver in colour but I suspect it was coated with something to make it look shiny like chrome.
I suspect I can only get the green colour if the metal is brass, copper or bronze but I figured I'd ask anyway.

Thanks!


So this isn't text only, here are just a few of the pieces I've put together over the last little while. The images are fairly big.