A Scottish 1944 50% one shilling from a car boot sale.
It was the same size as the circulating five pence coin and circulated alongside them until 1990.
You could get a collection of shillings from 1966 dating back to 1947 just by going through your change but I could never work out why I couldn't get any earlier ones.
It never occured to me that the same coin could be made out of different metals or that the metal of the coin had value or that the value could be more than five pence.
I guess that was back in the eary nineties, so well before silver stackers, no local coin shops, no idea that a shop could even sell used coins.
The Royal Mint sold all its coins through the local Post Offices. No internet at home and even if you went to one of the new shops with internet access and fired up netscape, the best browser in the world, there would be no web presence for old coins anyway.
Had to have it all explained to my by a guy selling second hand rubbish in a field at the weekend!
I only got started because I wanted to complete my shilling set.