Welcome to our second installment of Captivated by Colour and this time, we’re looking at pink diamonds. Pink diamonds are one of the rarest colours of diamonds and one of the most prized and valued. Many people will ask about coloured diamonds, but very few people know how rare they are, or how expensive they are. Diamonds are of course April’s birthstone and are still the most popular gemstone for engagement rings.

What gives pink diamonds their colour?

Whilst many diamond colours are a result of chemical impurities in the diamonds (for example, yellow diamonds are a result of nitrogen impurities), the colour in pink diamonds is a factor of something completely different. A GIA study of over 90,000 red, purple, pink and brown diamonds concluded that distortion in the crystal structure of a diamond gives rise to these fancy colours 99.5% of the time. In pink diamonds, the colour is generally concentrated along parallel narrow bands called lamellae, or glide planes. Interestingly, the atomic level distortions caused by plastic deformation that result in pink diamonds have not been replicated in a laboratory. Roughly translated, plastic deformation is a permanent change in shape of an item because of stress or force being applied to it.

Where do pink diamonds come from?

Pink diamonds have been found in many countries, including South Africa, Botswana, Canada, Tanzania, Russia and Brazil. However, Australia has been the world’s leading supplier of pink diamonds for decades, with approximately 90% of pink diamonds originating from the Argyle Diamond Mine in Western Australia. Not only is the Argyle mine the most prolific supplier of pink diamonds, it differs from all other primary diamond sources in that the host rock for the diamonds is lamproite, as opposed to kimberlite. To give you an idea of how rare pink diamonds are, only approximately 1% of the diamonds found in Argyle are pink. Most are brown in colour, but occasionally red, purple and violet colours are uncovered. These remarkable diamonds are auctioned every year during Argyle’s Pink Diamond Tender.

Tragically, Argyle Diamond Mine is due to close towards the end of 2020 after 35 years of operation, due to reduced economic viability.

Argyle Pink Diamonds

The “Hero” diamonds of 2019’s exclusive Argyle Diamond Tender. From left, to right: Argyle Verity, a 1.37-carat oval-shaped fancy vivid purplish-pink diamond; Argyle Enigma, a 1.75-carat modified radiant fancy red diamond; Argyle Amari, a 1.48-carat heart-shaped fancy vivid purplish-pink diamond; Argyle Opus, a 2.01-carat round fancy intense pink diamond;  Argyle Elysian, a 1.20-carat modified cushion-shaped fancy vivid pink diamond; Argyle Avenoir, a 1.07-carat oval-shaped fancy red diamond. Image: Rio Tinto

How are pink diamonds graded?

Like all fancy colour diamonds, pink diamonds have their own GIA colour grading scale. Clarity is graded in the same way as white diamonds, but the hue, saturation and tone of the pink, red or purple colour is really where the value comes from. Often, pink colour diamonds have underlying tones of other colours, and can be described as purplish-pink, orangey-pink and browny-pink (to name but a few examples). As is the case with yellow diamonds, pink diamonds that are graded as Fancy Vivid colours are the best possible quality.

Pink diamond grading scale

The GIA coloured diamond scale for pink diamonds. Image: GIA

How much is a pink diamond?

Pink diamonds are some of the most expensive diamonds in the world and regularly break price records when they go on auction. In 2017, the Pink Star, a 59.60ct Fancy Vivid Pink diamond sold for $71.2 million. For pink diamonds a little more practically sized, we’ve seen 0.10ct Fancy Intense Purplish-Pinks for $6600 (about R125,400) and 0.11ct Fancy Vivid Purplish-pinks for $14,500 (R275,500). Smaller diamonds, but still expensive! In South Africa, we have a 0.40ct Fancy Deep Pink round cut diamond priced at approximately $40,000 (R763,876).

Much talk is made of investment diamonds, and if you’re considering purchasing a pink diamond in South Africa, it’s worth noting that pink diamond prices have appreciated by about 116% over the last 10 years. With the looming closure of Argyle and a drop in the availability of pink diamonds, it makes sense that pink diamond prices will continue to rise.

Pink diamonds in South Africa

Two of the fancy pink diamonds currently available in South Africa through Katannuta Diamonds.

What are some famous pink diamonds? 

The Pink Star

As mentioned above, The Pink Star (formerly known as the Steinmetz Pink) is famous for a few reasons. It was initially offered on auction in 2013, where the highest bidder, Isaac Wolf, offered a record-breaking $83.1million for the diamond. However, after Wolf defaulted on payment for the stone, it was returned to Sotheby’s inventory, where they held onto it until 2017. At the second auction of the stone, it was sold for a record $71.2million to Chinese retailer Chow Tai Fook.

The diamond was mined by De Beers in South Africa in 1999, and the rough stone weighed a massive 132.5cts, and the cut stone is the largest known diamond to have been graded as a Vivid Pink.

Pink Star Pink Diamond

The Pink Star diamond (formerly the Steinmetz Pink). Image: Sotheby’s.

The Sweet Josephine

This 16.08ct Fancy Vivid Pink diamond was auctioned by Christie’s in November 2015. When the hammer fell at $28.5million, it’s new owner was Joseph Lau, a Hong Kong billionaire. Previously owned by an American family, the cushion cut diamond is also of South African diamond. Lau named the diamond after his daughter, Josephine.

Sweet Josephine Pink diamond

The Sweet Josephine pink diamond, purchased in 2015 by Joseph Lau. Image: Christie’s.

 

The Graff Pink

Laurence Graff is one of the world’s most accomplished diamond dealers. The founder and owner of Graff Diamonds, Graff is renowned for purchasing some of the world’s biggest and best diamonds. When Sotheby’s put a pink diamond from Harry Winston’s private collection up for auction in 2010, Graff was the highest bidder at $46million. However, Graff was not completely happy with the stone, and opted to repolish it, and by losing less than a carat in size, he managed to improve the colour grading (initially Fancy Intense) and the clarity (initially VVS1) of the diamond. Now, the Graff Pink is a magnificent 23.88ct rectangular cut gem, with an internally flawless clarity and Fancy Vivid colour grading.

The Graff Pink diamond

The Graff Pink diamond, previously owned by Harry Winston. Image:Sotheby’s

We hope that this has satisfied your thirst for information about pink diamonds, and now that you know how rare they are, you can appreciate their beauty even more. If you are looking for pink diamonds in Johannesburg or South Africa, and don’t want to pay retail jewellery store prices, reach out and contact us for a private diamond consultation. We’d be delighted to assist you with the perfect pink diamond.