Rough Diamonds: A Blue, Pink and Violet July

Almost 150 carats of colorful rough diamonds splashed the news in July. As we close out the month, let’s visit these blue, pink and violet creations of nature and their origins.

The Cullinan does it again

In 1905 the 3106.75 carat Cullinan diamond, the largest ever found, was unearthed at the Premiere mine in South Africa. On it’s 100th anniversary in 2003 the mine was renamed The Cullinan Diamond Mine.

Earlier this year the Cullinan mine produced an exceptional 39.34 carat blue Type IIb diamond. The stone traveled on a viewing tour which originated in Antwerp, Belgium, the world capital of rough diamonds. On July 12 Petra announced the sale of the diamond to a DeBeers’ and Diacore partnership for $40,180,180, which totals over $1 million per carat.

According to Petra CEO, Richard Duffy:

This sets a new milestone for Petra in achieving its highest price for a single stone and follows the sale of the 299 carat Type IIa white diamond in March this year and the five blue diamonds comprising the Letlapa Tala Collection in November 2020.

You can read about those five “blues brothers” in previous GemBlog coverage: Petra Diamonds Recovers 5 Blue Diamonds Totaling 85 carats.

It’s possible that this new exceptional blue could yield a record weight. Once polished, it could command a record price per carat, possibly in the neighborhood of $4 million per carat.

Lucara’s Joyful July

On July 14, at the Karowe Diamond Mine in Botswana, Lucara recovered a 62.70 fancy pink Type IIa rough diamond. This find was accompanied by others of similar color and purity, weighing 22.21 carats, 11.17 carats and 5.05 carats. The 62.70 carat pink, “Boitumelo”, translates to Joy in Setswana.

According to Lucara CEO Eira Thomas:

Lucara is delighted to announce another historic diamond with the recovery of the Boitumelo and very pleased to demonstrate the continued potential for large, colored diamonds from the South Lobe production. These remarkable pink diamonds join a collection of significant diamond recoveries in 2021 produced from the EM/PK(S) which forms a key economic driver for the proposed uncolored mine at Karowe.

This find is the largest fancy pink diamond recovery in Botswana and is one of the largest rough pink diamonds on record.

Pink diamonds derive their color in a different way than most fancy colored diamonds. The color is a result of distortions in those diamonds’ crystal lattice, resulting from immense heat and pressure after formation. That distortion displaces carbon atoms from their normal positions. This alters the qualities of light reflected within the diamond, resulting in pink appearance to the human eye. The Argyle mine produced 90% of the world’s pink diamonds from 1983-2020. Since its closure last year pink diamonds have seen a predictable increase in value.

The largest pink diamond on record is the Grand Table diamond, incorporated into the throne of the Mughal emperor Shah Jahan. Over 200 carats according to French adventurer and diamantaire Jean-Baptiste Tavernier in 1642, the diamond was lost to history. Today, some experts believe the 182 carat Daria-i-Noor and 60 carat Noor-ul-Ain may have started as part of the Great Table. You can read more about Tavernier and his exotic exploits in our previous GemBlog post, The French Blue, a story of travel, treasure and diamonds.

русский фиолетовый (Russian Violet)

Closing out our colorful month, Grib Diamonds reported selling $65 million in rough diamonds, including this 7.00 carat violet stone which sold for over $700,000, a total of more than $100,000 per carat. The majority of stones sold, including the violet crystal, came from the Arkhangelsk Oblast (Archangel Region) of northwestern Russia. Some rough sold originated in Angola.