Dudley North (1691):
I call to witness the vast Sums that have been coyned in England, since the free Coynage was set up; What is become of it all? no body believes it to be in the Nation, and it cannot well be all transported, the Penalties for so doing being so great. The case is plain, it being exported, as I verily believe little of it is, the Melting-Pot devours all.
What was the "free Coynage" referred to here? When was it "set up"? (Was it for example some specific law?)