Fancy Coloured Diamonds: Rarity, Value & Beauty
Fancy coloured diamonds are natural diamonds that exhibit intense colours beyond the typical white or colourless range. Unlike traditional diamonds graded on a D-to-Z colour scale (where lower grades indicate yellow or brown tints), fancy colour diamonds are valued for their saturation and rarity.
How Do Fancy Coloured Diamonds Get Their Colour?
Chemical Elements & Impurities
Nitrogen → Yellow & Orange Diamonds
Boron → Blue Diamonds
Hydrogen → Violet Diamonds
Crystal Lattice Distortions
Pink & Red Diamonds – Result from pressure-related distortions in the diamond’s atomic structure.
Green Diamonds – Exposed to natural radiation over millions of years.
Graphite & Other Inclusions
Black Diamonds (Carbonado) – Have numerous graphite or sulphide inclusions, giving them an opaque black appearance.
Types of Fancy Coloured Diamonds
Colour Cause of Colour Rarity Famous Examples
Pink Lattice distortion Extremely rare The Pink Star, Argyle Pink Diamonds
Red Lattice distortion Rarest of all The Moussaieff Red Diamond
Blue Boron impurity Very rare The Hope Diamond, The Blue Moon Diamond
Green Natural radiation exposure Rare The Dresden Green Diamond
Yellow Nitrogen impurity Common The Tiffany Yellow Diamond
Orange High nitrogen levels Very rare The Pumpkin Diamond
Purple Hydrogen impurity Rare The Supreme Purple Star
Brown (Champagne & Cognac) Structural defects Common Argyle Champagne Diamonds
Black Graphite inclusions Common The Black Orlov Diamond
White (Fancy White) Cloudy internal inclusions Rare The White Swan Diamond
How Fancy Colour Diamonds Are Graded?
Unlike colourless diamonds, fancy coloured diamonds are graded based on three main factors:
Hue – The primary colour (e.g., blue, pink, yellow).
Tone – Lightness or darkness of the colour.
Saturation – Intensity and strength of the colour (higher saturation means higher value).
GIA Fancy Colour Scale
Faint
Very Light
Light
Fancy Light
Fancy
Fancy Intense
Fancy Vivid (Highest value)
For example, a Fancy Vivid Pink Diamond is far more valuable than a Fancy Light Pink Diamond due to its stronger colour saturation.
Why Are Fancy Colour Diamonds So Valuable?
Extreme Rarity – Only 1 in 10,000 diamonds is a fancy colour diamond.
High Investment Value – Certain colours (Pink, Red, Blue, Green) appreciate over time.
Unique Beauty – Each coloured diamond is one of a kind.
Celebrity & Historical Demand – Famous diamonds increase awareness and desirability.