A new planning application says that illegal metal detecting has been spotted at the Grouville site at least twice since the discovery of the record-breaking Celtic Le Catillon II hoard in 2012.
In 1957, another significant hoard of Iron Age coins and jewellery was found in the same field.
The application, brought by Société Jersiaise, states: "This illicit practice not only strips the sites of their historical context but also robs future generations of a tangible connection to their heritage".
"Driven by the allure of valuable artefacts, these individuals willfully encroach upon archaeological sites, resulting in irreversible harm to these precious heritage locations", it adds.
They say a new survey of the site will be "non-invasive" and involve "field walking and metal detecting" designed to recover potential historical artefacts including Gaulish coins.
According to the planning application, the Grouville Centenier was contacted about one incident of illegal detecting in 2021 but "no individual has been caught nor prosecuted following the event".
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