When most people think of diamonds, they imagine a colourless, sparkling stone — but nature’s palette is far richer than that. Fancy coloured diamonds are among the rarest and most captivating gemstones in the world, offering vibrant hues that range from delicate pastels to vivid, saturated tones. For collectors, investors, and jewellery lovers alike, these extraordinary stones represent a perfect fusion of beauty, rarity, and prestige.
At Prins & Prins Diamonds, we are proud to offer expert guidance to clients exploring the mesmerising world of fancy coloured diamonds. In this guide, we explain what makes these gems so special, how their colours are formed, and what to consider when purchasing one of these exceptional treasures.
What Are Fancy Coloured Diamonds?
Unlike traditional white or colourless diamonds, which are graded based on the absence of colour, fancy coloured diamonds are prized specifically for their hue. When a diamond exhibits noticeable colour beyond the D-Z scale used for colourless diamonds, it enters the fancy colour category.
These rare diamonds display vibrant shades of:
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Yellow
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Pink
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Blue
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Green
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Orange
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Red
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Purple
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Brown (covered separately on the Prins & Prins blog)
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Grey and even black
The most valuable fancy coloured diamonds are those that exhibit strong, pure, and saturated hues, with minimal secondary tones or modifying colours.
How Fancy Coloured Diamonds Get Their Colour
The remarkable colours seen in fancy coloured diamonds are the result of complex natural processes that occur deep within the earth during the diamond’s formation. The presence of trace elements or structural distortions affects how light interacts with the diamond, creating the wide range of colours we see.
Yellow Diamonds
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Cause: The presence of nitrogen atoms replacing carbon atoms in the diamond’s crystal lattice.
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Effect: Absorbs blue light and reflects yellow, producing a range of canary to golden hues.
Blue Diamonds
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Cause: The presence of boron within the diamond’s structure.
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Effect: Absorbs yellow and red light, reflecting shades of blue.
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Notable Example: The famous Hope Diamond.
Pink and Red Diamonds
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Cause: Unique structural distortions (plastic deformation) during formation.
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Effect: Causes light to reflect in pink or red hues.
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Note: The exact cause of their colour remains one of nature’s most intriguing mysteries.
Green Diamonds
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Cause: Exposure to natural radiation over millions of years.
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Effect: Produces rare shades of green.
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Notable Example: The Dresden Green Diamond.
Other Colours
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Orange, Purple, Grey, and Chameleon Diamonds: Formed by various combinations of structural anomalies and trace elements, creating exceptionally rare colour variations.
The Rarity and Value of Fancy Coloured Diamonds
Fancy coloured diamonds are incredibly rare, accounting for less than 0.1% of all natural diamonds mined worldwide. Their rarity directly influences their value, which can often exceed that of high-quality colourless diamonds.
Factors influencing value include:
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Colour Intensity: The stronger and purer the hue, the higher the value.
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Saturation: Vivid, rich colours command premium prices.
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Size (Carat Weight): Large fancy coloured diamonds are exponentially rarer.
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Clarity: Less significant than colour, but still a consideration.
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Origin: Some mines, such as the Argyle Mine in Australia, produce uniquely coloured diamonds that carry additional prestige.
The closure of Australia’s Argyle Mine in 2020 has made Argyle pink diamonds even more sought after due to their scarcity and exceptional quality.
Famous Fancy Coloured Diamonds
Throughout history, certain fancy coloured diamonds have captivated the world:
The Hope Diamond (Blue)
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45.52 carats.
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Known for its deep blue hue and fascinating history.
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Housed at the Smithsonian Institution in Washington D.C.
The Pink Star (Pink)
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59.60 carats.
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The most expensive gemstone ever sold at auction.
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Noted for its flawless Fancy Vivid Pink grade.
The Dresden Green Diamond (Green)
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41 carats.
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The largest and finest natural green diamond in the world.
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Part of the Dresden Palace collection in Germany.
The Graff Vivid Yellow (Yellow)
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100.09 carats.
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One of the largest and most vivid yellow diamonds ever discovered.
These legendary gems represent the ultimate expression of rarity and beauty in the world of fancy coloured diamonds.
Understanding Colour Grading for Fancy Coloured Diamonds
Grading fancy coloured diamonds differs significantly from grading colourless stones. The Gemological Institute of America (GIA) grades these diamonds based on:
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Hue: The basic colour (e.g. pink, blue, yellow).
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Tone: The lightness or darkness of the colour.
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Saturation: The strength and purity of the colour.
Colour Intensity Levels (from least to most saturated):
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Faint
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Very Light
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Light
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Fancy Light
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Fancy
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Fancy Intense
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Fancy Vivid
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Fancy Deep
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Fancy Dark
The most valuable fancy coloured diamonds typically fall into the Fancy Intense and Fancy Vivid categories.
Tips for Buying Fancy Coloured Diamonds
Purchasing a fancy coloured diamond is an exciting and significant investment. Here are some expert tips to consider:
1️⃣ Work with a Reputable Jeweller
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Choose an experienced jeweller like Prins & Prins Diamonds who specialises in fancy coloured diamonds and offers transparent guidance.
2️⃣ Verify Certification
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Always request certification from recognised laboratories such as the GIA (Gemological Institute of America) or IGI (International Gemological Institute).
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Certification verifies natural origin, colour grading, and authenticity.
3️⃣ Prioritise Colour Over Size or Clarity
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In fancy coloured diamonds, colour drives value far more than clarity or carat weight.
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A smaller diamond with superior colour saturation may be far more valuable than a larger, paler stone.
4️⃣ Understand Treatments
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Some coloured diamonds are treated to enhance colour. Natural untreated stones command significantly higher prices.
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Always confirm whether a diamond’s colour is natural or treated.
5️⃣ Consider Investment Potential
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Rare colours such as pink, red, blue, and vivid yellow have historically appreciated in value.
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Fancy coloured diamonds may serve as both wearable art and a long-term investment.
The Timeless Appeal of Fancy Coloured Diamonds
Fancy coloured diamonds are nature’s most exquisite expression of individuality, offering an unparalleled combination of beauty, rarity, and prestige. Whether chosen for an engagement ring, personal collection, or long-term investment, these extraordinary gems continue to fascinate connoisseurs around the world.
Trust Prins & Prins Diamonds for Expert Guidance
At Prins & Prins Diamonds in Cape Town, our expert gemmologists are passionate about guiding clients through the world of fancy coloured diamonds. We offer carefully curated collections, bespoke design services, and expert certification — ensuring every client receives not only a stunning diamond, but complete peace of mind.
