Buying a loaf of bread with gold might prove problematic. Two bucks would be about a gram.
Gold as a money supply does indeed evaporate. It is worn away at a measurable rate per year and the more it must circulate the faster it will wear away.
Gold backed notes do not cause any wear on the gold. And we can use silver and gold for coin. Sorry Charlie, next time don't make a fool's argument and claim it comes from someone else's mouth.