Here in South Africa "china" is a common slang term for "friend." I hadn't the slightest idea where that came from, but today I learned that it comes from Cockney rhyming slang! For the unaware, CRS works by taking a word, choosing a rhyming phrase, then (in most cases) discarding the actual rhyme. Example: tiddly = tiddlywinks = drinks. Barney = Barney Rubble = trouble. For china, we have china = china plate = mate.
Anyway, that's your etymology for the day.