Pink Diamonds Guide: Argyle Rarity, Colour Grades and Prices

Pink diamonds are natural diamonds whose colour is generally attributed to a distortion of the crystal lattice deep inside the earth, and they rank among the scarcest gems in fine jewellery because the Argyle mine in Western Australia, once the source of more than 90% of global supply, closed in 2020. The British jeweller Boodles has bought Argyle pinks since 1998 and has been entrusted with the mine’s remaining stones, and Coveti now carries 52 Boodles pieces named for their pink diamonds, from diamond rings to earrings, pendants and bracelets.

I have spent the past weeks with the Boodles pink diamond pieces we now stock, and this guide is what I would tell a friend before she bought one: where the colour comes from, why supply is so tight, how the grading words work, what moves the price, and which pieces I would look at first.

Key facts

• The Argyle mine in Western Australia produced more than 90% of the world’s pink diamonds before it closed in 2020, according to Boodles.
• Even at its peak, less than 1% of Argyle’s total production was pink, and only 50 to 70 stones a year were judged exceptional enough for the Argyle Pink Diamonds Tender.
• Argyle pink diamonds formed over 1 billion years ago.
• Most coloured diamonds take their hue from trace elements; pink diamonds are believed to take theirs from intense pressure deep within the earth, a process gemmologists describe as plastic deformation.
• Pink diamonds are graded on hue, tone and saturation, with GIA colour grades running from Faint Pink to the rarest grades, including Fancy Deep Pink and Fancy Red.
• Boodles first bought Argyle pink diamonds in 1998, has been entrusted with the last remaining diamonds and the Argyle Pink Diamonds™ brand, and will use the remaining stones in its 2027 High Jewellery collection.
• At the time of writing, the Boodles pink diamond pieces at Coveti range from $7,200 to $1,213,590, and 28 of the 52 are rings.

What is a pink diamond?

A pink diamond is a natural diamond, made of the same carbon as a colourless stone, that shows a pink body colour. In the trade it belongs to the family of fancy coloured diamonds, a group that also includes yellow, blue, green and red stones.

What sets pink apart is how few exist. Yellow diamonds are found in many mines. Strong pink stones have come in meaningful numbers from essentially one place, and that place has stopped producing.

Pink diamonds are not the same as pink sapphires, which are a different mineral entirely, and they are not white diamonds with a coloured coating. A reputable grading report will state that the colour is natural.

Why are pink diamonds pink?

The honest answer, as Boodles itself puts it, is that the cause remains somewhat of a mystery. What gemmologists broadly agree on is the mechanism.

Plastic deformation, in plain terms

Under enormous heat and pressure deep in the earth, the carbon lattice of some diamonds is bent and twisted without breaking. This is called plastic deformation. The distortion changes the way the crystal absorbs light, and the stone appears pink to the eye.

The colour often sits in fine bands, sometimes called graining, rather than evenly through the stone. That is one reason cutting a pink diamond is a slow and careful job: the cutter has to orient the stone so the colour reads well from the top.

How this differs from other coloured diamonds

Yellow diamonds owe their colour largely to nitrogen. Blue diamonds owe theirs to boron. Pink stands apart because no trace element is responsible, which is why Boodles describes each one as shaped by forces we still do not fully understand.

How rare are pink diamonds?

Rare enough that a single mine closure changed the market. The figures below all come from Boodles, which worked directly with Argyle for more than two decades.

The Argyle mine

The Argyle mine in Western Australia was the world’s most significant source of pink diamonds, producing more than 90% of global supply. Yet even there, pink stones made up less than 1% of everything the mine produced. Argyle was also known for exceptionally rare red, blue and violet diamonds.

The Argyle Pink Diamonds Tender

Of the pinks Argyle did produce, only around 50 to 70 a year were considered fine enough to be offered through the Argyle Pink Diamonds Tender, one of the most exclusive diamond sales in the world. Before the mine closed, Boodles was invited into the Argyle Select Atelier Programme to handpick a number of important pink diamonds directly from the mine.

What the 2020 closure changed

Following the closure of Argyle in 2020, availability became finite. No new Argyle pinks are coming out of the ground, so every stone in circulation today is part of a fixed supply. According to Boodles, most of these diamonds have not yet been made into jewellery.

How are pink diamonds graded?

White diamonds are judged on how little colour they have. Coloured diamonds are judged on how much, and how good that colour is.

Hue, tone and saturation

Argyle’s unusual palette led to a proprietary colour grading system in the early 1980s, which is now internationally recognised. It assesses each stone on three things:

• Hue: the dominant colour.
• Tone: how light the colour is, through to how dark.
• Saturation: the strength of the colour.

Modifying colours can also appear. A Purplish Pink diamond, for example, is pink with a secondary purple note. Every Tender stone is also graded by the Gemological Institute of America (GIA) for colour and clarity.

The intensity terms you will see

GIA describes fancy coloured diamonds with a ladder of intensity words. The general rule, which Boodles also states, is that greater colour intensity indicates greater rarity and value.

What drives the price of a pink diamond?

The same four Cs apply, but in a different order of importance from a white stone.

Colour first

Intensity and purity of hue lead. A stone with a strong, pure pink will usually be valued well above a larger stone with a faint, brownish note.

Carat weight

Pink diamonds are mostly small. Boodles notes that carats measure weight, not size, and that “small and perfectly formed” is a good rule of thumb. In pink, a fraction of a carat is already a meaningful stone.

Cut and clarity

Cutters often favour shapes such as cushion, oval, pear and radiant, which can hold colour better than a classic round. Clarity matters, but buyers of pink usually trade some clarity for stronger colour.

Provenance and paperwork

A natural origin statement from a recognised laboratory is essential. Documented Argyle origin adds to a stone’s story and its desirability.

A note on value

Pink diamonds are scarce and have historically been sought after by collectors. That does not mean any individual stone will rise in price, and I would never suggest buying jewellery as a financial plan. Buy a pink diamond because you love wearing it.

What is Boodles’ connection to the Argyle mine?

For more than 25 years, Boodles has shared a close connection with Argyle pink diamonds. The family firm first bought Argyle pinks in 1998, and the colour has since become part of its design language, appearing in pieces from the Raindance collection. For the ring’s 20th anniversary in 2020, Boodles set Raindance in platinum with rare fancy pink and white diamonds.

That relationship has now entered a new chapter. Boodles has been entrusted with the last remaining Argyle diamonds and with the future of the Argyle Pink Diamonds™ brand. The remaining stones will form part of the Boodles 2027 High Jewellery collection. If you want the fuller family story, read who is Boodles.

Which Boodles pink diamond pieces can you buy at Coveti?

Of the 52 Boodles pieces named for their pink diamonds, 28 are rings, 16 are earrings, four are necklaces and four are bracelets. Settings are mostly platinum, rose gold and the two combined, with a few in yellow gold. Prices below are correct at the time of writing.

Under $50,000: a first pink diamond

• Secret Garden Pink Diamond Flower Ring, the most accessible entry point at $7,200, in rose gold and platinum.
• Classic Marquise and Pink Diamond Yellow Gold Eternity Ring, a pretty stacking band at $15,040.
• Ashoka and Pink Diamond Platinum Eternity Ring, pairing Boodles’ exclusive Ashoka cut with pink accents.
• Roulette Pink Diamond Rose Gold and Platinum Pendant, for colour worn close to the face.

$50,000 to $200,000: pink as the point

• Motherhood Platinum Pink Diamond Bangle, from the collection inspired by the National Gallery.
• Trilogy Diavik Oval Diamond Pink Diamond Shoulders Platinum Ring, a white centre stone framed by pink shoulders, which makes a strong engagement ring.
• Play of Light Platinum Pink Diamond Ring, also from The National Gallery collection.
• Raindance Pink Diamond Drop Earrings, the house signature translated into pink.

Above $200,000: collector pieces

• Vintage Oval Pink Diamond Platinum and Rose Gold Ring, a pink centre stone with a vintage feel.
• Decco Pink Diamond Platinum and Rose Gold Ring, a High Jewellery piece and one of the most significant pink rings in the edit.

Browse the full range across fine rings, fine drop earrings and diamond bracelets.

How should you buy a pink diamond ring?

“Pink diamond ring” is searched around 6,000 times a month in the US alone, and most of the questions I am asked fall into the five points below.

1. Decide between colour and size

With a fixed budget, a smaller stone with stronger colour usually gives more joy than a larger, paler one. Pinks are often used as accents for this reason, framing a white centre stone.

2. Read the grading report

Look for the colour grade, any modifying colour, and a statement of natural colour origin. If a seller cannot explain the report, keep looking.

3. Choose the metal with the colour in mind

Rose gold warms pink and makes a soft stone look stronger. Platinum and white gold keep the look cool and crisp. Many of the Boodles pink pieces at Coveti combine rose gold with platinum to get a little of both.

4. Think about the design

A single pink beside a white diamond makes a natural toi et moi ring, while a large pink centre stone works as a statement ring. If you are weighing colour more broadly, our guide to emerald, sapphire and ruby rings covers the coloured gem alternatives, and the engagement ring guide covers settings and sizing.

5. Compare houses

Boodles is the house to know for pink. For white diamond design you may also want to compare Cartier, Messika and David Yurman, all available at Coveti.

Frequently asked questions

Why are pink diamonds so rare?

Pink diamonds are rare because the Argyle mine, which produced more than 90% of the world’s supply, closed in 2020, and even there less than 1% of production was pink.

What makes a pink diamond pink?

A pink diamond’s colour is generally attributed to plastic deformation, a distortion of the crystal lattice under intense pressure deep in the earth, rather than to a trace element.

Where did most pink diamonds come from?

Most of the world’s pink diamonds came from the Argyle mine in Western Australia, which closed in 2020.

How are pink diamonds graded?

Pink diamonds are graded on hue, tone and saturation, and GIA colour grades run from Faint Pink to the rarest grades, including Fancy Deep Pink and Fancy Red.

What is the relationship between Boodles and Argyle?

Boodles has bought Argyle pink diamonds since 1998, has been entrusted with the mine’s last remaining diamonds and the Argyle Pink Diamonds brand, and will use those stones in its 2027 High Jewellery collection.

How much does a Boodles pink diamond ring cost at Coveti?

At the time of writing, Boodles rings named for their pink diamonds at Coveti range from $7,200 for the Secret Garden Pink Diamond Flower Ring to $597,510.

Are pink diamonds a good investment?

Pink diamonds are scarce and have historically been sought after by collectors, but no stone is guaranteed to rise in value, so they are best bought for the pleasure of wearing them.

How does Coveti deliver Boodles jewellery?

Coveti sells new, authenticated Boodles pieces with insured worldwide shipping by DHL Express and FedEx, mostly on a Delivered Duty Unpaid basis.

Shop Boodles at Coveti

Every Boodles piece at Coveti is new and authenticated, and ships insured worldwide by DHL Express and FedEx, mostly Delivered Duty Unpaid. Explore the full Boodles collection at Coveti, including all 52 pink diamond pieces, alongside the wider fine jewellery edit.