A silver ring found in a field by a metal detectorist has been dated back to Roman times and declared as treasure.

Oxfordshire Coroner's Court was told by an expert in archaeology that the incomplete silver ring dated back to the third century - meaning the precious item is more than 1,700 years old.

The finder, a man named Neil Cox, unearthed the item on November 25 last year as he was using his metal detector on agricultural land in Berinsfield.

The Roman finger ring has an oval bezel, which the expert Dr Matthew Fittock described as having a "scalloped appearance", and chevron decorations typical of the third century when finger rings became more ornate in their design.

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The Dorset Museum & Art Gallery in Dorchester has expressed an interest in acquiring the ring, the coroner heard.

The British Museum stated that because the ring is composed of over 10 per cent precious metal and pre-dates 1721, it qualifies as treasure.

The assistant coroner for Oxfordshire, Nicholas Graham, confirmed that was his finding and formally declared the ring to be treasure, meaning it comes under rules established in the 2023 Treasure Act.