What is the secret to pink diamonds?

We hear about pink diamonds everywhere. Beautiful pink diamonds that reach rocket high prices on auctions, and the prices just seem to go up and up.

Maybe you have asked yourself, why?

 Pink diamonds are a mystery of the earth. Nobody knows why they are pink. Other diamonds get their colour from chemical impurities which absorb the light. Yellow diamonds have traces of nitrogen in them, blue diamond’s contain boron. But nothing like this is found in pink diamonds. Scientists think the beautiful pink colour might be the result of a seismic shock which might have altered the diamonds molecular structure.

 'We have absolutely no idea where the colour comes from, and we will most likely never find out'.

The most beautiful pink diamonds are produced in North West Australia in the Argyle mine, owned by Rio Tinto mining company. It is only 40 years ago, the first pink diamond was found in Australia, and it took the company 10 years to start a mining operation, and start unveiling the beautiful stones from the centre of the earth. Before that time, the only pink diamonds known had a faint pinkish colour. Nothing at all like the saturated pink diamonds from Argyle.

But the pink diamonds from Argyle are so rare, that only a few are produced each year. Argyle makes 90% of the production of pink diamonds worldwide. Yet even though they move tons of earth each year to search for diamonds, you can still hold the yearly production of pink diamonds in one hand. That is how rare they are.

Each year, Argyle produce only 10 pink diamonds of 1 carat, brilliant cut. So no wonder prices are high.

The pink diamonds from Argyle increase minimum 20% in value each year. And the reasons are that:

1.    They are very very rare.

2.    There is a very high demand. Buyers really want to get their hands on these rare stones. Demand is increasing and supply is reducing, hence prices goes up.

3.    Mines are running out. It is estimated that in 2021, there will be no more pink diamonds found in the Argyle mine, or anywhere else.

The argyle mine has moved from above ground operations to underground, and the mine is drying out. And the deeper they dig, the more saturated and colourful are the diamonds, but they also find fewer and fewer.

So how are the pink diamonds sold?

At the Argyle pink diamond tender. Once a year 150 very serious bidders are invited to this event. The top 50-60 diamonds in superb colours, between 0,35 carats and 2 carats, will be traveling to secret locations in Sydney, Hong Kong, Tokyo, New York, London and Geneva. Here the bidders can see the stones, and they will have to give in a written offer by a specific date.

 It is very seldom that a buyer will bring home more than 1 or 2 diamonds. The prices are more than 200.000 USD pr. carat, depending on the colour of the diamonds. So these are really the most important diamonds in the world being sold on the Argyle pink diamond tender.

Grading pink diamonds

Pink diamonds are graded on their intensity of colour, not on their clarity.

There are 4 categories of colours for pink diamonds:

Purplish pink


Pink rose

Pink champagne

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But Argyle also produce diamonds of blue violet colours, and the very very expensive red diamonds, which are the rarest and the most expensive diamonds at all.

 The colour of pink diamonds is evaluated by the hue, which is the dominant colour, the tone, which is the light or darkness in the diamond and the saturation, which describes the strength of the hue. The saturation is described from faint to extremely rare vivid. And only the finest and most intensively coloured diamonds deserved the description vivid.

 Of the pink diamonds the vivid pure purplish pink called 1PP are the most expensive.

Buying sapphires directly from the source

I finally had a chance to go to Sri Lanka, the island of gemstones, a few weeks ago. As a passionate gemologist I hoped I would be able to get wonderful sapphires at a super low price when buying directly from the miner.

 I had prepared myself well. Read all available articles about sapphires, checked European suppliers and prices. Checked and rechecked all the sapphires I could get my hands on, so that I knew exactly what to look for in the field.

 I had also talked with lots of colleagues in the gem industry, who had recommended me trustworthy dealers. The first ones I went to, kept giving me glass, to check if I could see it was glass, and they asked me 3 times more pr. Carat than the gem dealers in Antwerpen. What a waste of time.

 But finally I found a dealer, who had beautiful, beautiful stones. All in amazing colors, fantastic cuts and he could recut any stone, into the exact measurements I was looking for. I was in heaven. I spent 1 full day going through all his stones, took my equipment to his show room, and made gemological tests of the gemstones I was most fond of.

 So what did I look for?

 We grade gemstones like diamonds, using the 4 C’s.





 But contrary to when buying diamonds where one looks for the perfect combination of the 4 C’s, when buying gemstones color is absolutely the first priority. COLOR IS KING. When grading color we look for the HUE, which is the basic color of the gemstones, it can be described as purplish pink, orangy yellow, greenish blue. We want as much of the real color as possible. To make an example we don’t want pink sapphire, to be purplish pink or orangy pink. We want them to be pink. Pink-pink. The second factor of a gemstones color is saturation, how much of the color is in the stone. Is it light, medium, vivid or intense. The more color the better. So, a pink sapphire, that is described as intense pink, is much more valid than a pink sapphire described as light purplish pink.

 The Clarity is not as important in gemstones. For diamonds, we want them to be with as little inclusions as possible, and in gemstones we would also prefer to have an inclusion free stone, but it is not always possible. To take an example, emeralds almost always have inclusions. So then you want to find a stone with as little visible inclusions as possible.

 The cut of gemstones is almost always native cut, which means that the cutter has cut the stone to show the best color. So, it can be a bit off centered, high or low pavilion, but it should always be symmetrical. It is really a matter of taste, some people don’t  mind if the cut of a gemstone is not perfect. But I look for symmetry, sharp well-proportioned facets and a beautiful stone, which shines and has life.

 Carat of a gemstone is the same as of carats in diamonds, 1 carat is 0.2 grams. But some gemstones are heavier than diamonds, so they will be physically smaller with the same carat weight. Quite important to bear in mind if you are looking for a gemstone to replace a diamond in a piece of jewellery.

 Treatment is a very import part of gemstones. Most gemstones are heat treated to bring out the color. Some gemstones, like the famous Tanzanite, was found as a brownish grey stone, but when heated it turned out to have a beautiful violet-bluish color, which is super sought after. Blue topaz is also a dull greyish color when mined, but after being heat treated it gets the vibrant blue colors we all love. There are many treatments of gemstones, and it will normally be described on the Certificate of the gemstone. Some gemstones don’t show a trace of treatment, but it is necessary and legally required for anyone selling a gem, to disclose the treatment procedure it may have received.  This doesn’t always happen, so it is important to know what to look for.

 There are different treatments used especially for gemstones. The most used is, as mentioned earlier, heat treatment.

 Another treatment is lattice diffusion, which is normally used for rubies and sapphires, where beryllium is diffused through the gem, and makes it change color. This treatment is very difficult to detect, which is also a good reason for only buying gemstones from a known and tested dealer.

 Fracture filling, is a treatment used mostly in diamonds and emeralds. It is a way of filling fractures naturally present in gemstones. The fractures are being filled with high-lead-content-glass, and sometimes even a colored agent to make, for example, the emeralds look greener. It is quite easy to detect for an experienced gemologist under magnification, as the filled fracture will have a different sheen than the rest of the stone.

 So over all it is quite challenging but fun to buy gemstones directly from the source. My advice is to not spend too much money on a single stone. You might be lucky or unlucky. So make sure that you love the stone, especially the color.

Art Deco, Elegance and Chic 1920-1930

To me, the most interesting period in jewellery design is the Art Deco. It is highly priced on auctions these days, and the design is easy to wear in a modern life style.

This is exactly how it was intended when the Art Deco was designed just after World War 1. Before World War 1, women didn’t work, and would wear huge dresses adorned from head to toe in jewels to reinforce the concept of helplessness. This changed during World War 1, where women had to work, while their husbands were fighting at the front. The women became more mature, business-like and favoured simple clothes and jewellery which was practical and simple in concept and design. Enjoying cocktails and cigarettes, wearing make-up, playing golf and tennis, driving, yachting and dancing till dawn were all part of the new woman.

Paris was still the epi center of artistic inspiration, and in 1925 there was a major exhibition in the centre of Paris named “Exposition Internationale des Arts Decoratifs et Industriels Modernes”, where several million visitors came to admire furniture, sculptures, glass, ceramics, silver and especially jewellery, where the principle in common to all was “new inspiration and real originality”.

This exhibition made a huge cultural impact and gave its name to a movement which is synonymous today with elegance and chic – Art Deco.

The lines of Art Deco include Fauvism, Cubisme and minimal geometric lines, and the simple, linear expressions was also adopted by Coco Chanel and Elsa Schiaparelli who launched elegant tailored suits for daywear, and evening gowns in silk, which was worn with long diamond earrings and ropes of pearls and sautoirs.

In 1922 Howard Carter discovered the tomb of the Egyptian boy king Tutankhamun, and this discovery inspired Parisian jewellers such as Cartier, Van Cleef and La cloche to create a range of Pharaonic bracelets, brooches, and clips. All set with clusters of emeralds, rubies, onyx and diamonds in Egyptian designs including hieroglyphics, pyramids, scarabs and lotus flowers.

The most popular gemstones in art deco jewellery are of course diamonds, but also Burmese rubies and sapphires and Colombian emeralds polished into sleek geometric shapes. This was for example rectangular step-cuts, triangles and squares, and diamonds were cut into the shape closely associated with Art Deco Jewellery, the baguette. This cut is ideal for slotting into geometric frames and contrasted perfectly with similarly shaped calibre-cut emeralds, rubies and sapphires.

The brilliant cut diamonds were also very ‘a la mode’ in 1920s, and they were well cut and would be set in regular lines or clusters.

The most beautiful jewellery of the art deco period is to me the bracelets, which started out in the 1920s by being pretty narrow lined bracelets and by 1930s they became broader, heavier and more angular. They can still be found in auctions or at antique jewellery shops, and are worth trying on.

Broches were also very popular in the Art Deco period, and is very popular for the moment, as it is easy to wear, and a wonderful different way of wearing jewellery. The sought after designs include bows and indeed the hoop brooch was the quintessential Art Deco jewel, which is made of a large ring of onyx or rock crystal between diamond chevron sides. Also the double clip brooches are very sought after, they are composed of a pair of identical “back-to-back” sections, each clip fastened on to a simple platinum or white gold frame. The double clip broches could be worn as a single jewel or dismantled to be attached to both lapels of a jacket.

Earrings from the Art Deco period are geometrically shaped, long and feminine, dangling from ear lobes, usually in linear designs set with diamonds, terminating to a featured, larger coloured gem. Normally they can be turned into broches.

Necklaces were extremely long sautoirs, and the iconic necklaces in the 1920s often featured a tassel, or geometric pendant. Long strands of beads and pearls were knotted carelessly around the neck, and worn down the front or back to finish the styling of the dress.

Rings, larger and more massive in the style with platforms and planes decorated by a myriad of gemstones. The center stone is often a coloured stone cut in cabochon or a large diamond, surrounded by a border of smaller diamonds. Large emerald cut stones, like emerald or aquamarine were very popular in the late 1920s.

What to look out for when buying Art Deco Jewellery:

Look for the general quality of the piece. You want it to be nice to the touch, have a nice finish. The design should be geometrical, or inspired by Egypt.

The gemstones need to be of a good cut, there is so much Art Deco jewellery of bad quality on the market. The sapphires can be man made, it is very common to find man made sapphires in Art Deco jewellery, and it doesn't really affect the price, except if the gemstone is the central stone of the piece. Check the diamond qualities, it is better to have brilliant cut diamonds, than single cuts. Also it is very important to check that the piece is actually made in the Art Deco period, and not a newly made copy.

Christie's, the jewellery archives revealed, by Vincent Meylan

Book review:

If you, like I, love jewellery, and the stories surrounding amazing jewellery, then you have to buy this book. It is the incredible story of the auction house Christies, written by jewels. It’s an incredible story telling of how specific jewels were inherited, between royals and celebrities and how they came to Christies.

Christies, which was founded by Mr Christie in London 250 years ago, had the first sale of royal jewellery in 1767, where some of the jewellery from Mary Queen of Scots, who was beheaded in 1587, was sold. 

Christie’s have sold jewellery from the British Royal Families, and also the crown jewels from France, Russia, Bavaria, Serbia, Egypt, India and Spain. All the stories behind these jewels are told in detail throughout this book in an extremely infatuating sense.  There’s a wonderful story of how incredibly valuable jewels were brought to Marie Antoinette before the French revolution, how she wore them, and who kept them safe, when Marie Antoinette was imprisoned, sentenced and beheaded. There are so many incredible stories regarding royal families all over Europe, on how their jewellery survived wars and revolutions. 

We read about Empress Josephine, the wife of Napoleon I, and Empress Eugine, wife of Napoleon III and many more, followed by Hollywood royalties like Elizabeth Taylor and Gloria Swanson, and continuing into the sale and history of some of the biggest and most valuable diamonds ever sold in an auction.

The author, Vincent Meylan, is a specialist in precious stones and high jewellery and has written several biographies about the history of precious stones, and he surely knows what he is talking about. Mr Meylan was granted full access to the archives of Christies and has the knowledge of both the jewellery and the history of the collectors, to tell their stories in the most eloquent way possible.

I thoroughly enjoyed this book; the images and stories are eloquently braided together to tell extremely amazing anecdotes in the most infatuating sense possible. 

Bluff diamonds - when size matters.

Bluff diamonds, which are essentially diamonds that appear bigger and better than they actually are, have become quite the new trend.

They are the diamonds to buy when size matters but you will need to be willing to go on compromise with clarity and colour. But there are of course many different kinds of bluff diamonds. So what do you need to look for?

A bluff diamond will normally be SI (Slightly Included) or I (Included) in clarity. Remember, that when grading the diamond, the graders look at how many inclusions the diamond has, but not necessarily at where the inclusions are located. Look carefully at the diamond, you want to find a diamond where you cannot see the inclusions in the middle of the diamond. You don’t want a black spot right under the table facet (the biggest facet on the top of the diamond)

But diamonds graded SI or I can also have some smaller inclusions at the side of the diamond, and this is the diamond you want to buy. The goldsmith can always hide the inclusions when setting the diamond.

The colour of bluff diamonds, are also important. You don’t want a diamond which is too yellow or brownish, but you need to be willing to compromise on the colour of the diamond.  Look for a diamond which is graded J or K in colour, they are normally a little bit yellow, but it is hard to see without a whiter diamond one could use as a comparison to the bluff diamond. And if you set the diamond in yellow gold, it will hide the yellow colour of the diamond.

Another way to get a cheaper diamond, is to compromise on the certificate. Diamonds with a certificate from GIA or HRD tends to be more expensive than diamonds with certificates from IGI or other grading institutes. You will therefore be able to ask for a lower price if the diamond doesn’t have certificate from GIA or HRD. If the diamond doesn’t have a certificate at all, it will be much cheaper, as the quality of the diamond isn’t verified.

Another way to get a cheaper diamond, is to buy a diamond off size. This is essentially a diamond which is just below the magic price jumps, which are 1, 1,5 , 2, 2.5, 3,4,5 carats etc. So if you can find a diamond of 1.8 carats, the price per carat will be lower than the price per carat of a 2 carats diamond.

And finally, diamonds in a fancy shape are cheaper than round brilliants. Normally you will get a fancy shaped diamond 10-15 percent cheaper than a round brilliant cut diamond. Fancy shapes are ovals, marquise, cushion, radiant etc. Don’t go for an emerald cut; it is almost impossible to hide inclusions in an emerald cut diamond.

The “perfect” bluff diamond is a big oval diamond, SI3 in clarity, J colour and of a 1.8 carat, with a good cut. The cut can also make the diamond look bigger than it is; if it is cut wider than normally recommended, it will look bigger than it actually is. Remember that the carat, is the actual weight of the diamond.

When buying bluff diamonds, you need to be critical, but willing to compromise. Look for a beautiful diamond, with sparkle, brilliance and fire. You need to think that the diamond is beautiful, and that you only see the beauty instead of the flaws. Then you will love it forever.

Diamonds at Auctions

A lot of people are asking me if it is worthwhile to buy diamonds at auctions. 

They have seen a super nice diamond, at a very low price at an auction house's webpage. And they ask me “isn’t this bargain just too good to be true?”

And yes, it is probably too good to be true. There is ALWAYS a catch on a cheap diamond. 

So what do I look for when I look at diamonds at auctions?

First of all I look very thoroughly at the diamond, preferably in natural light. Is it pretty? Does it reflect the light evenly? Does it show sparkle and fire??? How is the condition of the diamond? Is it chipped on the sides?  

Normally diamonds on sale at an auction, are 'graded-mounted'. This means that it is impossible to see all the inside of the diamond. It is impossible to grade a mounted diamond. You can have a look at it, and get a pretty good idea about the colour and clarity, but never the full version. 

When I grade a diamond, I always remove it from the mounting, clean it properly, and grade it, in a neutral environment, which means that I have the “diamond light” which essentially is a daylight-lamp. 

When I look at diamonds at auctions, I always look at the grading report the auction house has made, but it is very important to make your own judgement. 

Remember the 4 C’s of diamond grading 





In the information provided by the auction house, you should be able to see a colour grade, a carat weight, and a clarity grade. But remember that the diamond has been graded mounted. There can be inclusions hidden under the setting. 

The most important C is the Cut. The cut grade is never listed at diamonds on auctions and it is the most important. A diamond can have a beautiful colour, a good clarity and the perfect size. Yet a lot of the carat weight can be hidden in a bad cut. The diamond can have a very small diameter, but be very high. This means that the diamond will look smaller seen from above. Or it can be too flat, if the diameter is too big for the carat weight. A diamond cut too flat, will have what we call a “fish eye”, which is a darker ring around the centre, because it doesn’t reflect the light perfectly. 

For brilliant cut diamonds you should look for these diameters. 

A diamond of 1 carat should be 6.5 mm in diameter 

A diamond of 1.5 carat should be 7,5 mm

A diamond of 2 carats should be 8 mm

A diamond of 3 carats should be 9.4 mm

A diamond of 4 carats should be 10.4 mm

A diamond of 5 carats should be 11.2 mm

For fancy cut diamonds it is another story. When looking at a fancy cut diamond at an auction you need to judge if the cut is pretty. Is the oval cut diamond evenly oval, is it too long? Or is it too wide? Is the heart shape evenly? And pretty? Are the proportions correct in your opinion?  And so forth. 

It is very difficult to buy diamonds on auctions, you can be lucky, but get a professionals opinion before you bid on it. 

Is It Worth Buying HPHT Treated Diamonds?

I was offered this beautiful diamond from one of my diamond dealers in Antwerpen last month. The diamond on the photo looks amazing, but it was originally an unattractive brownish color, and has been treated with HPHT (High Preasure, High Temperature), which makes the diamond into this beautiful colorless stone. Diamonds can also be treated with HPHT to become pink, blue or canary yellow diamonds. 

HPHT treatment recreates the process that takes place deep inside the Earth's crust where diamonds were formed billions of years ago, to eliminate the structural disortations, that cause brownish coloring in some diamonds.  The temperatures get as high as 2.600 degrees Celcius, together with high pressure, and the result is a colorless, pink, blue or yellow diamond.  

The treatment is very difficult to detect, but all graded HPHT diamonds, will on the grading report have the little * after the color grade, with a note stating the treatment. An experienced diamond grader can detect the treatment when examining the diamond, if the diamonds has inclusions, these will normally change during HPHT treatment, and sometimes the enhanced diamonds will show hints of the original color when viewed from the side. Another point is that the HPHT treated diamonds tends to becomes magnetic and can be picked up by magnetic force. 

Clients should always be told that the diamond is treated. 

Prices on HPHT treated diamonds are much lower than non treated diamonds, up to 50 % cheaper. We don't see the same increase in prices of HPHT treated diamonds, as on non treated diamonds, so as an investment it is not optimal.  

Did I buy the diamond? No, I didn't, but I am still considering.