Norfolk has the highest number of recovered artefacts in the country declared treasure and a successful long-established working relationship with legitimate metal- detecting enthusiasts.
There were 109 cases of items found in Norfolk being declared treasure in 2008-09. Recent finds include a hoard of 24 Henry III short-cross pennies in Breckland, and an early Saxon gold spangle from south Norfolk.
But illegal metal detecting, known as “night-hawking”, is a big problem and Norfolk Archaeology Unit (NAU) is to prepare a briefing note for police safer neighbourhood teams outlining some of the worst affected areas.
Former Roman sites, such as Caistor St Edmund, are believed to be a particular target for night-hawkers, as well as the area around Snettisham in west Norfolk.
But night-hawking is a county-wide problem and has raised fears among archaeologists and legitimate metal- detecting groups that valuable artefacts are being lost – or sold online for profit.