TIME Team literally struck gold when they excavated the grounds of Codnor Castle last week.
Not only did the archaeological team date the castle much earlier than first thought, they also found what has been dubbed Time Team's most valuable single item find.
A gold coin discovered three-metres below ground at the foot of a moat caused the television team to jump for joy.
Presenter Tony Robinson said: "It's probably the most valuable single item we have ever found on Time Team. The other good thing about it, is that because it was in the bottom level of silt, it can tell us the date of the moat. Although people like these things because they are bright and shiny and cost a lot of money, the real value to us is that they are superb dating material and it helps to tell the story of Codnor."
Until detailed examinations are completed on the coin it is hard to value the find.
The coin was discovered by Jonathan Smith of Sandiacre, a stationary salesman by day, who does metal detecting as a hobby.
Jonathan said: "I was shaking, I have never seen anything like it."
Tony Robinson adds: "When he found it we tried to film it, but couldn't, as his hand was shaking with excitement . You have to imagine that this would be like dropping a 1,000 note in the moat, you can imagine what a knight would have said as it slowly found its way down to the bottom."
Despite the gold coin being the most valuable find on Time Team, it was two very small fragments of pottery that are most important for historians.
Time Team researcher Ben Knappett said: "We have an expert that knows absolutely everything about pottery. This is Stamfordware pottery from about 1150. But this has thrown the date of the castle to 1150 latest.
"We first thought the castle dated to 1308 as this is the first documentary evidence, but we now know that the latest date of the castle is 1150 as that is when this pottery stopped being made."
Another major find at the castle and yet another first for Time Team, was the discovery of evidence of a draw bridge. Tony Robinson added: "The show has been running since 1994 and this is the first time we have ever found evidence of a draw bridge."
The team along with archaeologists from Nottingham University also found remains of either a staircase or tower, a very thick curtain wall and the jury was still out on whether decorative curved stones found near to burnt animal bones was the remains of a kiln or if it was a garden feature.
Gavin Chamberlain from the Codnor Castle Preservation Society was overjoyed with the success of the dig, adding: "Its better than I ever imagined, it was me that put all the paper work together to get Time Team to visit and I have uncovered a right can of worms now."
The entire Time Team production squad was buzzing with excitement on the last day of the dig.
Tony Robinson added: "There are some Time Teams when we find absolutely nothing and of course they are depressing. There are then Time Teams where as soon as we dig, we sort of solve the puzzle of the dig and that is equally depressing in a way because it means we haven't got good programmes.
"What's so great about this dig is that we are constantly solving the puzzle and learning so much.
"All that was here when we arrived was a few ruins but nobody really knew what the castle looked like. We had no idea what archaeology we would find. Codnor Castle is very special, there are only two medieval castles in all of Derbyshire and it is amazing to think this ruin dates to a time of the War of the Roses and that there would have been knights walking around Codnor and Loscoe in armour."
For those eager to find out more, the programme is set to be aired between January and March next year.