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If the machines will not accept them without modifications, I doubt the coins will catch on.


I have read that the new $1 coins will have the same "signature" as the Sacagawea coins, so any vending machine that accepts the Sacagawea coins should accept the new coins without modification. So, you could put in a $5 bill and get both Sacagawea and George Washington $1 coins back in change now.