I was wondering the same thing.......
I recall a show about a farmer over there finding a mess of old Roman coins in a field he was tilling....all had to be turned over to the gov.
They did say that the 'finder's' are always fairly compensated, though.
“The Treasure Act of 1996 is an Act of Parliament designed to deal with finds of treasure in the United Kingdom. It legally obliges finders of objects which constitute a legally defined term of treasure to report their find to their local coroner within fourteen days. An inquest led by the coroner then determines whether the find constitutes treasure or not. If it is declared to be treasure then the owner must offer the item for sale to a museum at a price set by an independent board of antiquities experts. Only if a museum expresses no interest in the item, or is unable to purchase it, the owner can retain it.
‘Treasure’ is defined as being:
* All coins from the same hoard. A hoard is defined as two or more coins, as long as they are at least 300 years old when found. If they contain less than 10% gold or silver there must be at least 10 in the hoard for it to qualify.
* Two or more prehistoric base metal objects in association with one another
* Any individual (non-coin) find that is at least 300 years old and contains at least 10% gold or silver.
* Associated finds: any object of any material found in the same place as (or which had previously been together with) another object which is deemed treasure.
* Objects substantially made from gold or silver but are less than 300 years old, that have been deliberately hidden with the intention of recovery and whose owners or heirs are unknown.
“Under English law a landowner has sole title to any archaeological artifacts found on his or her property. Legitimate metal detectorists come to an agreement with the owners of the land they detect on to share any proceeds from treasure sales.
“Successful cases involving the Treasure Act include that of the Ringlemere gold cup. Non treasure finds are the remit of the Portable Antiquities Scheme.
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So since this is only one coin, it would not be a ‘treasure’ within the definition of the act. So it might belong to the landowner if the treasure hunter had not reached a binding agreement with him before beginning the hunt.
Since this is Great Britain, he will most likely be handing it over to a thug with a gun, knife, or box cutter at some time in the near future.