This being a purely academic discussion…gold would be $10,000/oz or greater, so I don’t think any fractional coins would be practical. A single 0.1 oz coin could buy too much. Silver would be a much better medium of exchange I think. The pre-1965 ‘junk’ silver quarters, dimes, and halves. As well as the bullion silver eagles, etc.
Storage will always be an issue. Silver would take a lot of volume and guarding it would be stressful and hazardous to your health.
