The castle is now reissuing its plea for help to track them down.
Following the theft in 2003, a castle steward raised the alarm after seeing the open cabinet. Five miniature portraits of Anne of Austria, Queen Mary I, Thomas Cromwell and Mary Queen of Scots were stolen.
In the intervening years two have been recovered: a circular miniature of Anne of Austria, in the style of Rubens, and a circular miniature of Queen Mary, in the style of Lucas de Heere.
But the other three have never been found.
With the assistance of Kent Police and art investigator Charley Hill a young man was arrested and sentenced to three years in youth custody.
At the time of the case the judge believed that others were involved in what he called a ‘professional theft’. Several members of gangs have been suspected, but 20 years on no one else has been charged or prosecuted in relation to the crime.
The three missing miniatures are: Thomas Cromwell from the studio of Hans Holbein (pictured, above top) and two portraits of Mary, Queen of Scots.
The three items are all on the Art Loss Register’s database.
Alison Palmer, curator at Hever Castle, said: “They are still very much missed from our collection and we have never given up hope of their return. Perhaps because of their size they can be more easily hidden, but they are undoubtedly recognisable. We hope that reminding the public of the theft will aid in their eventual recovery.
“We would urge anyone with information to come forward to Heritage Watch or the appropriate authorities. After 20 years the public deserve to see these important works on display once again.”
Hever Castle in Kent was the childhood home of Anne Boleyn. In the 15th and 16th centuries the Boleyn family added the Tudor dwelling within the walls. The castle was then owned by several families before William Waldorf Astor invested time, money and imagination in restoring the castle, building the ‘Tudor Village’ (now a hotel) and creating the gardens, lake and a golf course.
A Yorkshire family, the Guthries, are the current owners of the Hever Castle Estate.