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Feelin’ Blue
The Blues genre is a cyclic musical form characterized by a 7-note heptatonic scale, swing rhythm, a walking bass line, and “call and response” using specific harmonic progressions.
Huh?
It’s a steady, repeated groove.
Got it!
Like blues music, blue diamonds have a special character and appeal that’s all their own. And, like the aural call and response motifs that characterize blues-jazz, blue diamonds call out to each other, visually, in individual but harmonious combinations of hue, tone, and saturation.
Setting the Mood
When composing Everybody Loves The Blues, Maynard Ferguson may not have been thinking about diamonds, but he crafted a priceless musical gem, all the same. Click below to set the mood and enjoy the musical stylings of this jazz master, while we look at seven noteworthy blues from the Cullinan diamond mine: One for each note of a seven-step blues scale.
The Petra Blue
39.34-carats
In April 2021, Petra Diamonds announced the recovery of a 39.34-carat blue Type IIb diamond with exceptional color and clarity at the Cullinan mine. Prior to any viewings or sale, gemologist George Togholian, a consultant for the company which cut the extraordinary “Blue Moon of Josephine” (covered below) commented that photos of Petra’s 39-carat stone look strikingly like its Cullinan-cousin, possessing distinctive color and texture specific to blues extracted from that pipe.
“This is a special tone of blue. It’s not comparable to any other diamond that comes to auction. In my opinion, these are the best of the blues. This is on another level.” – George Togholian
Blues Progression
Blues music typically travels through a twelve-bar chord progression. Similarly, like a traveling band, the 39.34-carat Petra Blue Diamond also progressed from city to city, “performing live” in Antwerp, Dubai, Hong Kong, and New York before online bidding closed on July 12.
The final price commanded when the eGavel fell was $40,180,180, which exceeds $1M per carat – the highest price ever paid to Petra Diamonds for a single stone. It’s hoped that this new exceptional blue will yield a record weight, once polished, and command a record price per carat – possibly in the neighborhood of $4 million PC.
The Blues Brothers
85.60-carats
In September 2020, Petra reported a windfall extraction of five large blue Type IIb diamonds. Individually weighing 25.75 carats, 21.25 carats, 17.57 carats, 11.42 carats, and 9.61 carats, these spectacular siblings were said to be individual stones, not originally part of a larger diamond. Named the Letlapa Tala Collection, the diamonds were sold for $40.4 million at the end of 2020 to a partnership between DeBeers and Diacore.
Blues Patterns
In music, the blues follow a lyrical structure called AAB. In natural diamonds, blue color follows crystal structure defects, when a small number of boron atoms substitute for carbon atoms in the crystal lattice: A boron atom is one of a few elements small enough to enter the lattice and make such a substitution but it brings one less electron than a carbon atom. That means it’s not a perfect fit. This causes a defect in crystal structure which changes light transmission, selectively absorbing light in the red portion of the visible spectrum, while selectively transmitting light in the blue portion of that spectrum, so when light passing through the diamond reaches the human eye the observer sees blue.
Great blues music can be heard live in every major hub on our planet. However, blue diamonds are exceptionally rare. First, because boron is not commonly found in the deep earth environment where natural diamonds formed. Second, because the mere presence of boron doesn’t guarantee blue color. Nitrogen, which is far more common, can produce defects that reduce or counteract boron-induced color. Therefore, diamonds which present with strong blue coloration must contain very little nitrogen.
This is where the deposit at the Cullinan mine has distinguished itself, producing famous white Type IIa diamonds with little to no nitrogen, as well as the rich “blues brothers” seen here.
Blues Brothers Sidebar: For an illuminating retrospective on the band backing Jake and Elrod (the cinematic Blues Brothers), including notables like Paul Shaffer, Getdwa Jordan, and Bones Malone, check out True Blue: The Band Behind the Blues Brothers.
The Blue Moon
Back in January 2014, Petra announced that the Cullinan mine had produced an exceptionally colored 29.60-carat blue diamond. From the early days of discovery, it was predicted the crystal could sell for $15-20 million, despite the fact that it could potentially lose 60% of its weight during the polishing process. Those expectations were exceeded the following month when the diamond was sold to Cora International for $25.6 million, or $865,000 per carat.
In August 2014, after final polish, Cora unveiled the finished result of their purchase to the public. A perfect 12.03-carat Flawless, Fancy Vivid Blue combining the highest possible fancy color and clarity grades.
Double Time
In Jazz, double-time smoothly moves the tempo to twice its previous speed. The Blue Moon’s version of double-time occurred at Sotheby’s November 2015 auction when the polished diamond sold for nearly double the rough diamond’s price at $48.4 million. When you consider that price per carat was more than $4 million, it’s actually closer to double-double-time (in jazz that’s going to be tough on your drummer’s right hand!).
The diamond was bought by Hong Kong billionaire Joseph Lau, who named it for his seven-year-old daughter, whereupon it became “The Blue Moon of Josephine.”
Blues Scale
Located in the Gauteng province of South Africa, 25 miles east of Pretoria, “Mother Cullinan” be the world’s most important source of natural blue diamonds. Like a seven-note blues scale, she produced all seven of these richly colored stones above, fairly recently and fairly quickly.
She has also produced these notable finds in recent years:
- The Cullinan Heritage, a 507-carat rough white diamond, sold for $35.3 million in 2010.
- The Cullinan Dream, a 122-carat rough blue diamond, which sold for $25.3 million in 2016
- The Legacy of the Cullinan Diamond Mine, a 424-carat rough white diamond, sold for circa $15 million in May 2019
- A 20.08-carat Type IIb blue diamond, sold for $14.9 million in November 2019
- An exceptional 299.3-carat Type IIa white diamond, sold for $12.2 million in March 2021
Last, but certainly not least, she produced the 3,106.75-carat Cullinan Diamond in 1905, covered here in our previous post: The King Of Diamonds.
Get Your Fix
If you’d like to hear more exceptional blues music, start streaming some B.B. King, Stevie Ray Vaughan, Robert Johnson, Buddy Guy, or Muddy Waters. If you’d like to see more exceptional diamonds you can click on our Show Me The Bling! section, where fresh eye candy is posted daily.
May your audio and visuals always be harmonious.
Written by John Pollard
Comments?
Have you ever seen a blue diamond in person? Did you know the blue Hope Diamond, can be seen at The Smithsonian? Did you know, like the Hope Diamond, The Blue Moon of Josephine exhibits red phosphorescence when exposed to ultraviolet light? Do you know what, apart from boron, might cause blue color in diamonds? What do you think about fancy colored lab-grown diamonds? Will the value of natural FCDs increase or decrease in the future? Who is your favorite blues musician? What’s your favorite instrument?
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