For money to exist and function as such, it should be a universal metric and measure.
~
without even thinking about the world. did you know just in the U.S
a $10 bank note is near 2 hours labour in wyoming and georgia ($5.15 min wage)
a $10 bank note is near 1 hours labour in Connecticut and maryland($10.10 min wage)
a $10 bank note is near 50 minutes labour in Massachusetts ($12 min wage)
as for a loaf of bread.
going store to store i bet you will see an array of different prices for a basic loaf. all varying location to location
"universal metric and measure." pfft
I'm not sure what you want to say by that
Anyway, 10 dollars are 10 dollars anywhere across the States, be it Wyoming or Georgia, Connecticut or Maryland, or whatever. It just turns out that labor is priced and valued differently, and not just in America (read, it is not dollars that are different). I'm sure you will find startling discrepancies in the price of labor in different countries, but that has nothing to do with money as such (though you can use dollars pretty much anywhere, just in case). Regarding a loaf of bread, it looks like not all loaves of bread are born equal. But that's in the nature of things