How would the world economy hold up to a new international Global currency?

I don't know if I'm asking that right ...





What I'm wondering is if the entire world would benefit or not from a unit of currency (let's call it a "Terra" for arguments sake) that isn't based on any one nations currency but is based more on a Global market and backed by precious metals instead of any type of bank reserve notes.





Or does anything like it currently exist?|||Well, the dollar is the standard in some situations, but only as a custom or convenience, rather than a mandate.





But, yes, I believe that the world is ready for a global currency. All of the world's economies are closely tied together already. And, we have exchange rates for all of the currencies now. To me, it is a small jump to adopting a world currency. The banking and trade ramifications would be negligible, imho.