Easy way to create inflation is just to reprice gold overnight at some massively increased rate. Don't need to confiscate it, just say it is now worth $7000 an ounce. All of a sudden, you will have your inflation as all things are repriced. The US acts as broker / dealer & buys / sells to keep stability.

Problem is that gold is sort of out of favor (tellingly though, the central banks are mostly still buying. Except for Canada). But if not all parties have gold it be very disruptive to the financial system and the paper gold market would be very problematic.