This is a fun one--a threepence with a large die gouge in the shield (arrows). Something struck the die hard enough to raise metal around the gouge--see the gaps around the mark? Judging by the movement of metal, It's most likely this object struck the die before it was hardened--or perhaps it was a metal fragment that got hubbed into the die? A lot of coins were struck with this die--it's easy to eventually find one if you search eBay.