If there is a total economic collapse what is the guarantee that gold or silver will be worth anything at all? Frankly, if the monetary system is completely gone you couldn't buy 5 pounds of potatoes from me for less than 5 pounds of gold, or 10 pounds of silver.
I can't eat the gold or silver, can't heat my house with it, or gather or hunt food with it. Unless the person(s) you wish to do business with feel it has value it will not be as valuable as trading food, clothing or ammunition to get what you need.
There are two kinds of people, those that are prepared, and those that suffer.