Lovely find. Beautiful coin. Must have been so exciting to have found one that old.
I once found a George III half penny in a garden of a property built in the 1950s. The person who lived in the property had lived there for over 40 years and was a very keen gardener. So the soil would have been dug over many times. It would also have been overturned quite dramatically with the construction of the property in the 50s. Before the house was built, the area was just open farmland.
In spite of that, I found the coin on the surface as if it had just been dropped there the day before.
The date on the coin is 1779. Having just had a quick look on the internet it seems that the value of the coin at the time would be just over three pounds of today's money.
What I found interesting was to find out that the coin was a forgery... and a very poor one at that.
There were many of these fake coins in circulation at the time, to such an extent that they became a big factor to the economy, along side the royal mint.
It was common in those days for workshop owners to pay the wages of their workers with fake coins. There were many workshops in the town near to where I found the coin so could easily explain how the coin got there.
Not quite as exciting as a Henry III silver penny but I enjoyed finding out about the coin anyway.
But it's interesting to think that the coin you found had been lost for 500 years before the one I found had even been produced.