Cash has always been misunderstood. Actual hard currency is just a symbol used to balance values between two disparate things by somehow assigning a numeric value in common units (of cash). There is a part of monetary theory that says that the value of something is measured by how much work we put into it. Gold and silver coinage are merely symbols representing specific amounts of that work.
Before strict economists jump on my stuff, I know there are other models. I like this one. Besides, since I used this idea in one of my novels for my writing hobby, I had to look into it a bit. At least one model says that money is just an accounting unit and that some folks incorrectly assign value to it when in fact it inherently has no value other than that which is assigned to it.
Got doubts? Look at international money exchanges and contemplate that at the moment, the Russian Ruble is worth 0.011 dollars. That is the value currently assigned to the Russian Ruble.