If I’m not mistaken, the United Kingdom has a law against keeping “his mouth shut”, and all archeological / historical finds must be turned over to the authorities for inspection and valuation.
However, the treasure hunter and land-owners are each given 50% of the items value after the artifact is inspected and valued.
Yeah, it would be nice if he were able to keep it, but unlike the US gubmint, the UK gives fair compensation to the person that finds the treasure. In the USA, the gubmint would just keep it and then send you tax bill for finging it.
This guy is not going home empty handed.
I am stunned if they are that fair.