This seems like a good place for this.
We just found a stash of old coins. It's amazing what you find when you clean closets. A dozen or so are pennies from when they were still made of copper, they have been in a leather wallet for decades, and are really green. How can I clean them so I can read the years? The few I can read are 1910-1930.
Also any suggestions on where I can look to see if any are worth more than face value?