A beautiful gold rosary carried by Mary Queen of Scots to her execution at Fotheringhay Castle in 1587 was among items taken by thieves in a burglary at Arundel Castle.
The castle is the historic seat of the Catholic Dukes of Norfolk in West Sussex. As well as the beads the thieves got away with gold and silver items worth more than £1 million.
Coronation cups given by the Sovereign to the Earl Marshal of the day were also taken when a display case in the castle was smashed open.
Alarms at the castle were triggered at 10:30pm on Friday night.
A spokesman for Sussex Police said that while the rosary is of little value as metal, “as a piece of the Howard family history and the nation’s Catholic and royal heritage, it is an irreplaceable item.”
A spokesman for Arundel Castle Trustees said: “The stolen items have significant monetary value, but as unique artefacts of the Duke of Norfolk’s collection have immeasurably greater and priceless historical importance.
“We therefore urge anyone with information to come forward to the police to assist them in returning these treasures back where they belong.”
Police added that officers were on the scene within minutes. Detective Constable Molly O’Malley, of Chichester CID, said: “If you were in Arundel on Friday evening and saw any suspicious activity around the area of the Castle, please contact us either online or by calling 101, quoting Operation Deuce.
“In addition, the castle only re-opened to visitors on Tuesday 18th May so if you were visiting during the past few days do you on reflection recall anyone behaving at all suspiciously? If you are offered or hear of anyone offering for sale any of the items stolen, we would also like to hear from you.”
The force added that Crimestoppers can be contacted anonymously on 0800 555 111.
Arundel Castle welcomed visitors back last week amid the easing of lockdown restrictions. The building, which had remained closed over winter to carry out essential restoration work, dates back to the 11th century.