The midnight-blue silk velvet dress designed by Victor Edelstein sold for 800,000 Canadian dollars (£510,000). Diana wore the Edwardian-inspired gown with off-the-shoulder straps while taking a memorable spin on the dance floor with Travolta during a 1985 White House state dinner.
Prior to Thursday night's sale, auction house Waddington's had listed the estimated selling price of the dress between 800,000 Canadian dollars and 1 million Canadian dollars.
