If you're lucky enough to find some 'treasure', you're legally obliged to report it. A coroner then decides whether it's actually treasure. Yes, there's a legal definition of treasure, and you can't just pocket it, even if you've found it. This goes for all the amazing finds, mostly from metal detectorists over the years, including the Crusader's Sword, the Galloway Hoard, and the Ringlemere Cup. Though not everyone plays by the rules, and there have been plenty of scandals in cases like the Herefordshire Hoard, where pieces were stolen and sold to dealers.

In this episode of Gone Medieval, Dr Cat Jarman is joined by Professor Michael Lewis, Head of Portable Antiquities & Treasure at The British Museum to define what treasure is, what happens if you've found some and more about the Portable Antiquities Scheme, which gets involved when a piece might not be legally considered treasure, but still holds some cultural or historic value