Roman jewellery uncovered during the renovation of a Colchester department store is thought to be one of the finest ever finds in Britain and has been described as “of national importance”.

The treasure was discovered as part of excavations by the Colchester Archaeological Trust beneath Williams & Griffin in the High Street during £30million expansion works.

The collection, thought to be that of a wealthy Roman woman, includes three gold armlets, a silver chain necklace and two silver bracelets.

A substantial silver armlet, a small bag of coins and a small jewellery box containing two sets of gold earrings and four gold finger rings were also in the find, and conservation work is expected to reveal more objects.

Philip Crummy, Colchester Archaeological Trust director, said: “This discovery is of national importance.

“We have been working on the site for six months and this remarkable Roman jewellery collection was discovered on the third to last day of our dig.

“Our team removed the find undisturbed along with its surrounding soil, so that the individual items could be carefully uncovered and recorded under controlled conditions off-site.

“The find will be transferred to a secure laboratory, where a conservator will clean and stabilise the items and deal with the fine traces of delicate organic remains that survive, such as leather and wood.”

The Roman treasure was buried in the floor of a house which was subsequently burnt to the ground during the Boudiccan Revolt in AD61.

It is likely the owner, or one of her slaves, buried the jewellery for safe-keeping during the early stages of Boudicca’s revolt.

Colchester was subjected to a two-day siege before the small force of soldiers stationed in the town folded. A number of noble women were taken to sacred groves and killed horrifically.

The revolt left a distinctive red and black layer of debris up to half a metre thick under the centre of much of modern day Colchester, consisting of the remains of the burnt clay walls and other fragments.

Human remains are rarely found amongst this layer, but the Williams & Griffin excavation produced a small but important collection, including part of a jaw and shin bone.

These appear to have been cut by a heavy, sharp implement such as a sword, suggesting that at least one person fought and died in the vicinity during the revolt.

Mr Crummy added: “We also discovered food that was never eaten on the floor of the room in which the jewellery was found, including dates, figs, wheat, peas and grain. Others will almost certainly be identified when soil samples are examined by specialists.

“Foodstuffs like these do not generally survive, but in this instance they were carbonised by the heat of the fire, which perfectly preserved their shapes.

“Evidently, some of the food had been stored on a wooden shelf, which had collapsed on to the floor. The dates appear to have been kept on this shelf in a square wooden bowl.”

Hugo Fenwick, trading director at the Fenwick Group which owns Williams & Griffin, said: “We were pleased to fund this excavation at our store as part of its redevelopment programme.

“There was always a very real possibility of unearthing a significant find in the centre of Colchester, with its antiquity and stature as Britain’s oldest recorded town. We are delighted that the archaeologists found this treasure during the very last week of their excavations, strengthening our understanding of this important Roman town and the ferocity of the Boudiccan raid.”

The find has been reported to the coroner who will rule on its legal status.

Fenwick Limited said it wishes to waive its right to any reward it might be entitled to under the Treasure Act and wants to offer the treasure to a local or national museum at no public expense.

The find reaffirms Colchester’s Romans links. How much do you know about the town’s history? Take our photo quiz here and find out