In 2008 the laboratory celebrated its centenary, where the current Duke of Northumberland led festivities.
He was succeeded to the Dukedom by his younger brother Lord Ralph Percy.
In March 2011, Khalid married Lucy Cuthbert, the niece of Duke of Northumberland at a ceremony attended by a handful of guests.
After a huge public appeal the Madonna of the Pinks was bought in 2004 by the National Gallery from the Duke of Northumberland for £34.88 million, with contributions from the Heritage Lottery Fund and the National Art Collections Fund.
Shortly afterwards, in 1991, he identified the Madonna of the Pinks belonging to the Duke of Northumberland as a genuine Raphael, and not a copy of a lost original as was previously supposed.
Northumberland | Duke University | Duke Ellington | Duke | Duke of Wellington | Ralph Waldo Emerson | Ralph Lauren | Ralph Nader | Prince William, Duke of Cambridge | Ralph Vaughan Williams | Duke of York | Percy Bysshe Shelley | 12th United States Congress | Ralph Fiennes | Duke of Norfolk | Duke of Edinburgh | Duke of Burgundy | Ralph Steadman | Prince Arthur, Duke of Connaught and Strathearn | George Villiers, 1st Duke of Buckingham | Prince Andrew, Duke of York | Percy Grainger | Duke of Northumberland | Alfred, Duke of Saxe-Coburg and Gotha | Ralph Macchio | Ralph Bunche | Prince Richard, Duke of Gloucester | Prince Frederick, Duke of York and Albany | George Duke | Charles Lennox, 2nd Duke of Richmond |