The Paradox of Currency

precious metals are ideally suited to serve as currency, being durable, portable and able to be endlessly subdivided into identical portions. Different nations have been made use of by different nations for this purpose. Iron was the common instrument of commerce among the ancient spartans, copper among the ancient romans, and gold and silver among all rich and commercial nations. Using irregular metal ingots is easier than barter, but wouldn't standardizing the units, say, stamping pieces of metal with uniform designations make things easier still? And so was coinage born.