A SOLID silver seal from the 16th or 17th century was found in a field near Loxwood, an inquest heard.
Metal detectorist Bill Weights discovered the artefact on April 21 last year.
Mr Weights was on a site owned by Simon Carter, who had given permission for him to be there.
He gave the seal to Sussex finds liaison officer Stephanie Smith. She said it was solid silver, with a fluted design and a fleur de lys motif. It has been dated to between 1580 and 1699.
West Sussex assistant deputy coroner Christopher Wilkinson ruled that the seal was treasure, because of its age and silver content. The British Museum has expressed an interest in buying it.