On March 11, 1988, the Centenary celebration of the DeBeers Company was being held in Kimberly Western Australia, to commemorate the closing of the “Big Hole”, the Kimberly Mine. A speech was given to celebrate the day and to announce, surprisingly, the find of a 599 carat diamond of top color having been found in the Premier Mine in South Africa. Dignitaries and representatives from national governments and the diamond industry were in attendance.
The Centenary diamond was found on July 17, 1986 using the x-ray recovery system. Many of the largest diamonds, for instance, the Cullinan in 1905, the Niarches in 1954, the Taylor-Burton in 1966 and the Premier Rose in 1978 were found in the Premier Mine.
Gabi Tolkowsky, a very accomplished diamond cutter was chosen by DeBeers to evaluate and cut the diamond. He was amazed at its excellent “purity” and color. He could tell just by looking at the surface without looking inside. After deliberating over the diamond, his advice was to keep the diamond intact to produce one large modern-cut diamond.
Along with Tolkowsky, it took a crew of people to successfully cut the diamond. The crew included two master cutters, Geoff Woolett, Jim Nash and a group of electricians, engineers and security guards. The special room for cutting in the DeBeers Diamond Research Laboratory in Johannesburg, South Africa needed to be free of vibrations around the cutting table and special tools were needed for faceting.
It took over a year to accumulate the right tools and to create the perfect environment. By then, Tolkowski knew everything about the diamond. It took him 154 days to remove 50 carats of diamond rough. At that point, the Centenary diamond looked like a rounded egg weighing 520 carats. Thirteen different designs were given to the DeBeers board for consideration but the recommendation was a modified heart shape.
After cutting the diamond, it weighed 273.85 carats with 247 facets. It was the largest number of facets given to a diamond. The Centenary diamond was insured for $100 million. It was sold to a private collector who is unknown to this day.