Not quite at Stacker-status, but yeah when we got beyond our first goal, we hold a very small % of assets in Precious metals, primarily split between gold and silver.
Our intent was diversification. I guess if I had to come up with a rule, it would be 1-5 % of portfolio above 1mm in precious metals as gold/silver. As one goes down this road there is palladium and copper but that feels like a different form of speculation on industrial materials. Everything is held as physical metals, not in etfs, not in rented warehouse space were you don't know if they have enough to cover yours and certainly not in any leveraged financial etf/product, that's how people really F up an IRA...
There is a lot of inflation and end of days talk around Precious metals, so to be clear, if you are worried about rampant inflation I think the best hedge is improving your job skills or adding new marketable ones.