Something of this story needs explanation.
Shropshire is on the English/Welsh border and there are many gold mines in Wales and nuggets in the size range of this one have been found there in recent times. Over the long period of history many more would have been found. It is conceivable that a Welsh nugget may have been lost by a traveller from Wales to England.
The value of gold was known in Europe from a very early age so it is probably less conceivable that even a prehistoric human may have abandoned it as appeared to have happened with the Boort nugget in Victoria. That nugget was found in an old aboriginal campsite quite a distance the nearest gold field Wedderburn.
Other explanations are that the nugget was transported by glaciers or that Shropshire does hide an unknown goldfield.
A final explanation could be a fraudulent plant to achieve value from its sale by claiming it to be the largest gold nugget found under English soil. A Welsh nugget of just 30g, named the Prince of Wales nugget found and authenticated a few years back sold for 20000 POUNDS at auction because of its rarity.
The fact that the prospector was late to go with the group and found the nugget without any genuine witnesses sounds a bit suss.
These days detailed compositional analysis can generally determine the source of gold, and if any buyer were to want to pay the sorts of prices being bandied around, they would be wise to have that done.
