Colored diamonds are extraordinarily rare, and the rarest color of all is red. With its final lot on Monday night, Christie's New York set a world record when a 3.15-carat fancy reddish-orange diamond sold for $2.09 million, or $666,200 per carat, at its Magnificent Jewels auction. The final price soared above the pre-sale high estimate of $1.2 million. Christie's reported that this exceptional diamond was the largest of this color ever offered at auction.
How rare are natural fancy red diamonds? Gemologists believe that there are fewer than 100 in existence and most of these weigh less than one-half carat. Only three are larger than 5 carats. The 3.15-carat specimen sold by Christie's is a member of a very elite club.
Unlike other colored diamonds – such as blue diamonds that get their color from the addition of boron in their chemical composition, or green diamonds that are impacted by natural radiation – red diamonds are not colored by impurities. Rather, their color is the result of minute defects in the crystal lattice.
The top lot of the day at Christie's was a rectangular-cut, D-color 50.01-carat diamond ring by Graff, which sold for $8.37 million. The massive center diamond is flanked on either side by a tapered baguette-cut diamond and mounted in platinum. Interestingly, the original designer, Laurence Graff, purchased the ring.
“This is the third time that I have owned this beautiful diamond and I am as thrilled today as I was the first time. Diamonds of this exceptional caliber have a life and legacy that carries on beyond us all,” noted Graff after the sale. “This is one of the finest D-color diamonds in the world and I am delighted to have it back again.”
Graff purchased the same ring for $4.2 million at a Christie's auction in 2005, according to Rahul Kadakia, head of jewelry for Christie's Americas and Switzerland. The near doubling of the price over seven years demonstrates "the increasing strength and stability of the global diamond market," he said.