"Gresham's Law" I bet you keep the better coin! See this goes back to the history of gold/silver coins and human behavior.
From history:
Nicolas Oresme, a Catholic bishop (1320-1382), studied human behavior with regard to money, which in his time consisted of gold and silver coins; he was perhaps the first to observe that humans attribute varying valuations to the money that comes into their hands. He stated that hodlers of gold and silver coins prefer to tender their most deteriorated coins in payments, and retain the brightest, shiniest and most perfect of their coins. Thus, he was the true originator of what has come to be known as "Gresham's Law", long before an English man named Thomas Gresham made a similar observation during the reign of Queen Elizabeth I (1558-1603).
Commentary:
Now its time to hodl that coin, for in order to find worth- something has to come from - without worth.
Sources:
Plata.com.mx
thedirtisgoodtome.com