So you can't buy stuff with this new money, huh?

Is there a date stamp I should look for on my money so I know if it is "worthless" new money, or good old money?
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She was standin' alone over by the juke box, like she'd something to sell.
I said "baby, what's the goin' price?" She told me to go to hell.

Bon Scott - Shot Down in Flames