A METAL detectorist who discovered a hoard of Roman coins in a farmer's field has had his find officially declared treasure.

Warren Cave's 1,700-year-old haul and three other local discoveries were granted treasure status by Oxfordshire coroner Darren Salter on Wednesday.

Mr Cave, who lives with wife Tracy in Brightwell-cum-Sotwell, had been metal detecting for 16 years and never found real treasure when he struck silver in December 2014.

The professional roofer recalled: "I was roofing in Wallingford on the Friday and finished about 2pm so I thought I would go over to a field I knew in North Moreton.

"I'd been to that field a few times before and it had been no good at all, but I thought I would give it a go."

After an hour during which he found nothing but some Victorian halfpennies and a button, it started to get dark.

He said: "I started heading back to my Landrover then my detector started to buzz erratically.

"The light was fading but I had a dig and the first find was a small Roman coin.

"Then I dug up a silver siliqua (another Roman coin), then five more in a row, then 10 more."

Not believing his luck, Mr Cave kept unearthing more coins until he had a hoard of 50. But, by that time, the light was gone and he had no choice but to leave.

He recalled: "I didn't sleep much that night – I was like a kid waiting for Christmas morning."

Unable to keep his secret, he rang metal detecting buddy Paul Jones, who featured in this paper in October when he dug up a 3,000-year-old axe head in South Oxfordshire.

Mr Cave said: "Paul was over the moon - it was great."

The next morning the pair raced back to the field and started digging again.

They unearthed more than 50 more coins, and when they were sure the search was exhausted, took they haul home and called the queen of treasure in Oxfordshire: finds liaison officer Anni Byard, who helps acquire locally-discovered treasure for Oxfordshire Museums Service.

Ms Byard sent the haul to British Museum experts who worked out the coins were late fourth century Roman, mostly copper alloy nummi, but also two late 4th century siliqua in "very fine condition".

On Wednesday at Oxford Coroner's Court, Ms Byard watched as the haul was officially declared treasure.

The coroner also declared treasure a Medieval gold brooch dug up by Chinnor metal detectorist Kevin Ford in a field near his home in August and a Medieval silver ring and Medieval silver belt end, both dug up by West Oxfordshire detectorist Noel Rice.

Ms Byard said the rectangular brooch, dating from AD 1230 to 1350, stood out because it was in "very fine condition".

She added: "This brooch is unusual because of its quality and completeness: you could almost wear it now, and considering it's about 800 years old, that is very nice".

All the treasure will now be valued by experts at the British Museum.