The US Mint makes coins for circulation and sells them at face value to the FED RESERVE to be sold to the banks. Currently the Mint only produces 4 coins for general circulation, penny, nickel, dime and quarter. The penny and the nickel are losers and the dime and quarter are winners in terms of profits for the Mint. Overall the Mint makes a profit for the US Treasury even when you only consider the circulation coin business. In addition the Mint makes proof and mint sets, commeratives, bullion coins and NIFCs that are sold well above face value.
The overall profit on circulating coins is low because of the rising costs of production and the absence of higher value coins ($1/2, $1, $2) that would bring a greater profit.
If the US Gov't stopped making $1 bills and thus there was a demand for dollar coins the profits for the Mint would be in the hundreds of millions.
Therefore my solution to help boost the profitability of the US Mint:
Stop making pennies for general distribution, only include them in mint and proof sets. Cash transactions will be round to the nearist 5 cents
Change the nickel, dime and quarter to nickel plated steel
Stop making $1 and $2 bills
Introduce a $2 coin
Not that the Govt is in the mood for descive action