Serious question regarding PM after the financial System comes to its end.

So when the financial system as we know it eventually reaches its end how will Precious Metals be used as a replacement?

There's currently 7.1 Billion people on this earth today and im sure there's no where near enough PM to form a stable currency.

If it were used as a temporary currency that seems logical but nothing more.

I feel like im missing something very obvious here but could you guys enlighten me. All i see happening is like i stated above, PM would be used temporarily then they would bring in a currency similar to the one now but on a global scale and completely reset.