Well, five years later but I'm obliged to respond. I purchased some relics and bullets years ago from the aforementioned dealer and was duped. Most of the items were legitimately dug and written on by Mac Mason. Others were not. The lettering on some of the bullets were in Mac's style but were just a little off. These included Enfield bullets still currently being sold from Gettysburg and Petersburg. The lettering is just too thin. When I purchased the lot from the dealer he said it would include copies of two letters from Mac to Richard Ross, an old digging buddy. One was to contain a list of all the places he dug, including Gettysburg and Antietam. That was what I wanted to hear. Unfortunately, I only received one letter, which was legit and even listed a lockplate I was purchasing. I pursued this "other letter" for years from the dealer. Finally it was "in the mail". Not. It eventually broke down to my texts and calls being ignored.
Fast forward a few years and I make contact with Steve Henry and his wife, Joyce. Steve was one of Mac's digging partners for years. They answered some questions I had, mainly, "What did Mac use to write on his bullets and if he dug at Gettysburg or Antietam ". I was told Mac used a Speedball pen and ink and that, to their knowledge, never dug at Gettysburg or Antietam. Ian Workman, you were right! Luckily, it was only about ten bullets but it happened to a guy who thought he knew better, me. I own a few hundred of his items and thought I was smarter than the average bear. Live and learn.
My printer is down or I'd scan the letter I did receive. Maybe Mike can scan and post it. I think it's pretty cool.