I will qualify that under a limited economic crisis, one where the electronic form of transaction may have failed, but limited supply lines are still functioning and central government is still intact, some vendors may place greater value on minted stock than regular currency. There could be anticipation of a general revaluation of currency following a limited crisis whereby conversion loss would be far less with precious metals. I am thinking in terms like what happened to Iraqi dinar and how conversion helped some of the wealthier from losing a lot of their inherent value. That is a bit of a fine line, though.