"Things You Wouldn't Know If We Didn't Blog Intermittently."
Not gold related, but still interesting - There are a fair number of people who make it their hobby to clean old tarnished bronze/copper coins.see: 
That is a curious hobby, because most numismatists frown on even attempting to clean coins for fear of damaging it or removing a nice patina.Perhaps with ancient coins and junk coins there is a different ethos.
I like to clean, polish and add patina to old, tarnished coins to make jewelry. My goal is to emphasize their beauty so that people can see the artistry that was involved in making them. But these are not rare, investment coins. They may be 50, even 100 years old, and demonetized, but not scarce. My reasoning is that wearing them reveals them to more people than storing them in an album. People have used coins to make jewelry since ancient times.