Joseph Lau Luen-Hung, a Hong Kong real estate investor, made the winning bid via telephone and the right to name the diamond. The rare, internally flawless cushion-cut stone—which was the centrepiece of Sotheby’s Magnificent Jewels auction in Geneva—is now known as the ‘Star of Josephine.’
The $9.5-million bid is the most paid at auction for a fancy vivid blue and a record-breaking $1,349,752 per carat. Pre-sale estimates put the diamond’s price at $5.8 to $8.5 million.
It surpasses the previous record holder—a pear-shaped, 3.73-carat vivid blue diamond that sold for $1,328,444 per carat last year.
The Cullinan mine is world-famous for its blue diamonds. It is located at the foothills of the Magaliesberg mountain range, 50 km northeast of Pretoria in South Africa.
