IT WAS a chance discovery which turned out to be the biggest hoard of historic coins found in modern times and could be worth more than £1m.

Armed with a metal detector Southampton man Paul Coleman, who almost didn't bother digging down, unearthed the unique cache of more than 5,000 Saxon coins.

Now that historic stash, which tool more than five-and-a-half hours to dig up, has been officially declared a treasure trove.

The coins included a uniquely stamped coin made as a result of a mix-up at the mint and some which coincidentally had the finder's surname written on them.

No modern valuation has yet officially been placed on the coins but experts said that the hoard's contemporary worth was three times that of the manor where they were found.

Some experts estimated the hoard to be worth more than £1 million.

The coroner at the treasure trove inquest heard that Mr Coleman made the discovery on December 21 last year when he was out with fellow members of his metal detecting club the Weekend Wanderers.

Mr Coleman said: "I wasn't going to go but I was talked into it.

"When the detector started beeping, it felt like the size of a manhole cover and that's also what caused me to nearly not dig it up. Anything of that size is normally a manhole cover or a squashed bucket."

Retired Mr Coleman, aged 60 years, said it was fate that caused him to wander over to where the hoard was buried, choosing a different course because his Deus detector was receiving interference from one belonging to another member of the metal detecting club.

What he found were 985 coins dating from the reign of Ethelred the Unready in the 990s and a further 4,263 that were minted during the reign of his successor, Canute.

The hoard, found in a field near the village of Lenborough, Buckinghamshire, was taken to the county museum in Aylesbury before then being sent to the British Museum for further analysis.

Brett Thorn, keeper of archaeology at the Buckinghamshire County Museum, told the treasure inquest: "For the agricultural workers living there at the time, a few pennies would have been a significant sum to them. This is a very, very large sum of money."

Mr Thorn said the most likely theory as to how such a large hoard came to be buried was that the coins were on their way to a mint in Buckingham, five miles away, to be melted down and re-cast. He added however that it could also represent the savings of a single family accumulated over a 20 year period.

He added one of the coins - an Agnus Dei coin containing a lamb and flag - was possibly unique to history.

"This is a massively significant find, which is why we were really pleased the British Museum said they were happy to let us have it", he said.

Mr Thorn said the museum hoped to be able to secure funding to allow a student to carry out a PhD doctorate on the find.

Some of the coins were inscribed with the name Coleman. Mr Coleman added: "I joked that the hoard had my name on it - I didn't realise it literally did. The whole thing has been surreal the whole time."

Coroner Richard Hulett ruled that the hoard should be counted as treasure after hearing the coins were made of more than 10 per cent silver - the minimum level needed to satisfy modern treasure laws.