I actually mentioned something similar in a previous post on my website. My figures were a little different (and I think silver was worth upwards of $30 at the time of writing): http://simplefactsplainarguments.blogspot.com/2013/02/minimu...
"UPDATE: If you want to understand what really hurts low-income workers, look at the value of our money. In 1956, the minimum wage was $1.00/hr. However, our coins (dimes, quarters, half-dollars and dollars) were still made with silver back then. For an 8-hour work day, a minimum wage worker in 1956 would earn 32 silver quarters. How much is that worth today? About $170. How much would a 2013 worker make with a minimum wage of $9/hour? $72. 'Nuff said."
Simple Facts and Plain Arguments
A common sense take on politics and current events.