Gold is a universal make-believe store of wealth: it is precious because "we" (i.e. most people) agree to consider it as precious. The fact that it's rare, cannot be manufactured and doesn't corrode over time are nice to have properties but are neither necessary nor sufficient conditions of value.
The context of this subthread is SHTF situations, where all that matters is inherent value determined by the laws of nature. What good is your gold if nobody wants to take it for even a tuna sandwich or if you have a loaded gun pointed at you?