Aside from the physical impossibility of the posited scenario…
As a thought experiment, let’s turn it on its head: Let’s imagine the (also nearly unimaginable*) discovery of quantities of gold and other precious metals scattered around the globe that dwarf what has already been refined and carefully stored because of its scarcity and perceived value. In other words, what would happen if the valuable suddenly became valueless?
After all, it amounts to the same thing, right? Except in the case you posited the thing of value has disappeared, leaving no value, the opposite is to be covered up with the stuff which now has no value because of its commonplace nature.
And what @josie has predicted is what would happen. There would be a period of upheaval as balance sheets were adjusted, because many people and institutions have relied upon precious metals as a store of value, which would no longer exist. And after that upheaval, life would go on and new stores of value and means of exchange would be developed.
*EDIT: Not “unimaginary”. Duh.