For anyone interested in a good history of using gold as money, Peter Bernstein's The power of gold: the history of an obsession is worth looking into:

* https://www.goodreads.com/book/show/249245.The_Power_of_Gold

Money: The True Story of a Made-Up Thing by Jacob Goldstein (of NPR's Planet Money) is also good:

* https://www.goodreads.com/en/book/show/50358103-money