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Nature's Brilliant Colours
Newsletter No. 41 11/2020

Dear Customers, Clients and Friends:
An eventful year is drawing to an end.
As always, we are confident that we will all overcome this crisis. And, although common sense is definitely called for, we can still enjoy the little things in life!
In this newsletter, we are starting our series: "The ABCs of Coloured Diamonds" to refresh or complete your knowledge. Enjoy!
Due to current events, and as travel and trade fairs are not possible for us at the moment and it’s probably not a good idea to visit you either, we would like to share some new, as well as some existing treasures from our extensive inventory. We have recently added a large number of champagne coloured pairs to our stock. All pairs are in the perfect Hearts & Arrows pattern.
We look forward to hearing from you - and as always, we would be happy to put together offers and selections based on your ideas and customer requests.
With best wishes for an excellent Christmas trade!
Sincerely yours
Juliane Hennig and the Kulsen & Hennig and Dominik Kulsen AG Teams
Argyle & Antwerp
Argyle - The Argyle diamond mine in North West Australia is, or rather, was, the top source of pink diamonds. It is also known for its large yield of champagne coloured diamonds in the most beautiful shades of brown. The operator of the mine, Rio Tinto, has decided to close down the mine in the near future due to the ever-decreasing yield and the increasing costs of mining.
If you are interested in champagne coloured diamonds with a certificate of origin from the Argyle mine, please contact us!
Antwerp - This city was already a famous diamond centre as early as the 16th century. Although most diamonds today are cut in India, Antwerp is still considered the capital of the world’s diamond trade. More than 80% of rough diamonds and 50% of cut diamonds pass through the Hovenierstraat in Antwerp, where many global diamond traders can be found. And while this port city may be best known for its painters and fashion princes, it also has a lot to offer holiday travellers. In this lively seaport town you can, for example, follow in the footsteps of the baroque painter Peter Paul Rubens.
Baby Blue or Baby Pink?
Did you know that up until about a 100 years ago, most people were completely unfamiliar with the idea of assigning a colour to a gender? It was only at the beginning of the 20th century that - and here it comes! - pink was introduced for boys and blue for girls. The change in these colours took place in the mid-1930s with the advent of new military uniforms, blue jeans, and worker's dungarees.
 And not just pink and blue dyed clothes have been in fashion since then - the same is true for diamonds! A new blue or pink diamond is often purchased and worked into the original wedding ring to commemorate the birth of a son or daughter.
Natural blue coloured diamonds are among the rarest in the world. They get their colour from the chemical element boron, which is embedded in the crystal lattice during the creation of the diamond. Colour-treated blue diamonds get their colour afterwards through artificial, radioactive irradiation.
In practice, these two can be distinguished as follows: Natural blue diamonds can conduct electricity, but irradiated, and thus treated, diamonds cannot!
Pink diamonds get their colour from the very high pressure and extreme heat found in the earth's interior which shift the levels of the carbon crystal lattice as the diamond is formed. Pink is also among the rarest diamond colours found in nature.
The 4Cs - Colour, Cut, Clarity, Carat - and the 5th C
The 4 Cs - Colour, Cut, Clarity and Carat (weight) - are the quality characteristics that determine the value of a diamond.
Colour: Colourless diamonds are assigned letters ranging from D to Z. The letter “D” stands for the highest quality white colour level. From colour level I onwards, the stones have an increasing colour tone.
Natural Fancy Coloured Diamonds are given the prefix Fancy if they show a clearly visible colour. Example: Fancy Yellow
Cut: A diamond can only display its full brilliance when cut in the right proportions. It depends above all on the skill of the cutter who creates a masterpiece out of a rough diamond. A good cut brings out the fire of a diamond optimally: the light is reflected from one facet to another and shines back through the surface of the stone.
Clarity: Purity, the measure of the inclusions of a diamond, is evaluated by the visibility of these features under 10x magnification. In the case of Natural Fancy Coloured Diamonds, clarity is a less important consideration than the colour, as long as the inclusions do not affect the brilliance of the stone.
Carat: The weight of a diamond is indicated in carats. In the past, diamonds were weighed against the seeds of the carob tree, which weigh 0.2 grams per seed. This is the origin of today's unit of measurement: 1 carat = 0.2 grams.
The weight of diamonds in everyday use can also be given in points: one carat consists of 100 points, so the weight of a diamond of 50 points corresponds to 0.50 carats. Example: A one-point diamond equals 0.01 ct, a ten-point diamond 0.10 ct.
The Fifth "C" - Confidence! The purchase of a diamond and also the purchase of the piece of jewellery made with it is always a matter of trust. Despite the possibility of obtaining certificates, trust and expertise are essential to the diamond trade. This is especially true for coloured diamonds, which can have very different appearances. Anyone who is looking to make some easy money and gets involved with strangers in a seemingly unique and fast transaction usually experiences disillusionment.
Deep & Dark
When grading Natural Fancy Coloured Diamonds, it is not just the colour that counts, but also the colour intensity.
In addition to the names for the colour gradations “Faint” (barely visible) – “Very Light” – “Light” – “Fancy Light” – “Fancy” – “Fancy Intense” – “Fancy Vivid” (bright / lush), there are also “Fancy Deep” and “Fancy Dark”. The terms “Deep” and “Dark” are used when a diamond displays a rather dark and muted colour impression.
“Deep” is mainly used for diamonds that contain the colours yellow, orange, or green.
Expertise & ExExEx

A diamond expertise (also called a certificate) is issued by a gemmological institute or diamond expert after a thorough examination of the diamond. The expertise provides information about the authenticity and the quality features that determine identity and value.
The following institutes are internationally the best known and most recognised:
What does “ExExEx" or "Triple X" mean?

An ExExEx diamond or Triple X diamond is a brilliant cut diamond that has an excellent cut, excellent symmetry, and excellent polish. X is the abbreviation for Excellent. Triple X therefore means Triple Excellent. Such a diamond gives off maximum light and fire.
Whether or not a diamond exhibits fluorescence can only be determined under UV light in the dark.
Stones without fluorescence remain dark under UV light. The stronger the fluorescence of a diamond, the more it glows under UV light. Since UV rays are also contained in sunlight, the colour of fluorescent diamonds appears somewhat different under the influence of strong sunlight than under artificial light.
While colourless diamonds usually lose value through fluorescence, this is not always the case with coloured diamonds. Fluorescence can also be interesting, for example, when a yellow diamond shows a yellow fluorescence. This can intensify the colour. How the fluorescence impacts the price of a stone, however, must be examined on a case-by-case basis.
It is interesting to note that all chameleon diamonds are fluorescent. Champagne coloured diamonds also very often show fluorescence.
Fluorescence can appear in different colours too, from a whitish colour, to blue, to yellow.
From Our Collection
Baguette / 1.01 ct / Fancy Greenish Yellow Brown / VVS / 6.74 x 4.50 x 3.32 mm
Radiant / 0.47 ct / Fancy Deep Brownish Yellowish Orange / VS / 4.52 x 4.38 x 2.84 mm
Radiant / 0.45 ct / Fancy Vivid Orange Yellow / SI2 / 4.09 x 3.92 x 3.15 mm / GIA
Marquise / 0.38 ct / Fancy Deep Yellow Orange / VVS / 6.52 x 3.74 x 2.58 mm
Brilliant pair / total: 0.75 ct / C2 / VVS - VVS / H&A*
Brilliant pair / total: 1.10 ct / C4 / VS - VVS / H&A*
Brilliant pair / total: 1.55 ct / C3 / VS - VVS / H&A*
Brilliant pair / total: 2.09 ct / C5 / SI - VS / H&A*
*The "Hearts and Arrows" pattern (H&A) indicates diamonds that have excellent optical symmetry and thus an outstanding cut quality. It consists of eight hearts and eight arrows, which must be clearly symmetrical and identifiable.
Brilliant / 0.50 ct / Fancy Deep Brownish Orange / SI / 4.83 x 4.84 x 3.29 mm
Oval / 0.72 ct / Fancy Brownish Greenish Yellow / SI1 / 6.90 x 4.40 x 3.03 mm / GIA 
Brilliant / 1.05 ct / Fancy Vivid Yellow / VVS2 / 6.51 x 6.54 x 4.02 mm / GIA
Brilliant / 1.21 ct / Fancy Gray / SI / 6.65 x 6.67 x 4.22 mm
Cushion / 0.55 ct / Fancy Deep Olive Green / SI / 4.78 x 4.65 x 3.10 mm
Princess / 1.04 ct Fancy Brownish Gray / SI / 5.50 x 5.26 x 4.23 mm
Oval / 1.07 ct Fancy Deep Olive Green / VVS / 7.68 x 5.69 x 3.63 mm 
Brilliant / 1.71 ct / Fancy Pinkish Brown / VS / 7.45 x 7.51 x 4.81 mm
Oval / 2.11 ctC2 / VS / 9.58 x 7.19 x 4.66 mm
Cushion / 3.23 ct C3 / VVS / 8.71 x 7.80 x 5.51 mm
Marquise / 3.51 ctC5 / SI / 15.01 x 7.17 x 5.21 mm
Brilliant / 3.51 ctC2 / VVS / 9.70 x 9.73 x 6.00 mm

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KULSEN & HENNIG GbR | POB 2 10 63 | 10122 Berlin | T +49 (0)30 400 55 93 0 |
DOMINIK KULSEN AG | POB 2033 | 8401 Winterthur | T +41 (0)52 212 24 40 |