What Makes Pink Diamonds Like the Record-Setting CTF Pink Star So Valuable

By Sotheby's

S ince summer 2018, Sotheby’s has been offering curated online auctions of loose diamonds, sourced by Diacore, the company responsible for the CTF Pink Star, which after selling at Sotheby’s Hong Kong in April 2017, became the world auction record for any diamond or jewel. The current Diamonds Online | Capsule Collection (17–24 October | Online) roster includes three stunning groups of pink diamonds, one of which will be sold to benefit the Breast Cancer Research Foundation. Ahead, discover upcoming pink diamonds, revisit the beauty of the record-setting CTP Pink Star and learn what makes pink diamonds so rare.

The CTF Pink Star:

A 59.60-carat oval mixed-cut Fancy Vivid Pink internally flawless diamond, the CTF Pink Star sold for an astounding HK$553 million ($71.2 million). Besides being the largest Internally Flawless Fancy Vivid Pink diamond that the Gemological Institute of America (GIA) has ever graded, the CTF Pink Star also received the highest color and clarity grades from the GIA for pink diamonds. Mined by De Beers in Africa in 1999, the 132.5-carat rough diamond was meticulously cut and polished over a period of two years and transformed into a stunning gemstone, thanks to Diacore.

A model displays The CTF Pink Star , a 59.60-carat oval mixed-cut pink diamond. Photo by studioEAST/Getty Images.  

What makes a pink or red diamond?

This is actually an impossible question to answer, as there is no impurity that causes its color, only the evidence that these diamonds have a mutation within their crystal lattice that alters the stone’s molecular structure. With enough of these “defect centers,” the diamond may take on different properties. For example, the diamond could absorb a certain wavelength of green light, resulting in a pink appearance. Other colors, such as green, purple and orange, occur from natural radiation and other common elements within the Earth.

Upcoming Pink Diamond Lots:

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