Just to divulge a little, can I ask how you can possibly a Half Penny expert aged 15? Please don't think me rude, but real study to expert status in any given field takes a lot of time and learning. I appreciate you have a geniune interest and a wonderful growing collection, but I dont think you're quite up with Dr Nicolson yet. I probably know more about halfpennies than you, but I wouldn't even think about calling myself an expert, not for at least 20 years! Tone it down a bit old chap, or you'll end up getting invited for Mastermind or something.