Red & Orange Diamonds
| Property | Details |
|---|
| Cause of Color (Red) | Extreme crystal lattice distortion (same mechanism as pink, greater intensity) |
| Cause of Color (Orange) | Nitrogen combined with structural defects |
| Rarity | Red: Rarest diamond color. Orange: Exceptionally rare |
| GIA Grades (Red) | “Fancy Red” only — no intensity modifiers (Vivid, Intense, etc.) |
| GIA Grades (Orange) | Fancy Light Orange through Fancy Vivid Orange |
| Famous Red Examples | Moussaieff Red (5.11 ct), Hancock Red (0.95 ct), De Young Red (5.03 ct) |
| Famous Orange Examples | The Pumpkin Diamond (5.54 ct), The Orange (14.82 ct) |
| Price Range (1ct, natural) | Red: $300,000–$2,000,000+; Orange: $30,000–$300,000+ |
Red Diamonds: The Rarest Gems on Earth
Red diamonds are the single rarest color of diamond — and arguably the rarest gemstone of any kind. Fewer than 30 true red diamonds are known to exist, and the largest ever found, the Moussaieff Red, is only 5.11 carats. To put their rarity in perspective: for every million carats of rough diamonds mined worldwide, approximately one red diamond might be found. Most years, none are found at all.
Red diamonds owe their color to the same crystal lattice distortion (plastic deformation) that produces pink. The difference is degree: red diamonds exhibit an extreme level of lattice distortion that absorbs enough green and blue light to transmit a pure red. They are essentially the most intensely colored pink diamonds in existence.
GIA Grading of Red Diamonds
Red diamonds receive a unique treatment in the GIA grading system. Because the color is already at maximum saturation, there is no “Fancy Vivid Red” or “Fancy Intense Red.” All qualifying stones are simply graded “Fancy Red.” They are the only fancy color that uses a single grade with no intensity scale. If a diamond shows slightly less color, it would be graded as a dark or vivid pink rather than red.
Famous Red Diamonds
The Moussaieff Red (5.11 ct): The largest known red diamond, originally found as a 13.9-carat rough in Brazil in the 1990s. Cut into a triangular brilliant (trilliant), it was purchased by the Moussaieff jewelry house. Its value is estimated at over $20 million.
The Hancock Red (0.95 ct): A small but historically significant red diamond that sold at Christie's in 1987 for $880,000 — at the time, $926,000 per carat, the highest price per carat ever paid for any gemstone at auction. This sale put red diamonds on the map as the ultimate collector stones.
The De Young Red (5.03 ct): Originally purchased as a “brown ruby” at a flea market, this round brilliant was later identified as a natural red diamond. It is now displayed at the Smithsonian Institution alongside the Hope Diamond.
Orange Diamonds
Orange diamonds are the second rarest fancy color after red. Their color comes from a combination of nitrogen atoms arranged in specific configurations and structural defects in the crystal lattice. Pure orange — without brown, yellow, or pink modifiers — is exceptionally uncommon.
Unlike red diamonds, orange diamonds are graded across the full GIA intensity scale, with Fancy Vivid Orange being the most valuable and rarest grade.
Famous Orange Diamonds
The Pumpkin Diamond (5.54 ct): A Fancy Vivid Orange diamond purchased by Ronald Winston (of Harry Winston) at auction in 1997. It was famously worn by Halle Berry to the 2002 Academy Awards. Its name comes from the purchase date: the day before Halloween.
The Orange (14.82 ct): The largest Fancy Vivid Orange diamond known. Sold at Christie's Geneva in 2013 for $35.5 million ($2.4 million per carat). Its origin and history before the sale were largely unknown, adding to its mystique.
Natural vs Treated
Natural red: So rare that virtually no treated or lab-grown reds exist in the market at comparable quality. Any red diamond offered without major lab certification should be viewed with extreme skepticism.
Natural orange: Also very rare. HPHT treatment can produce orange diamonds from certain starting material, and these must be disclosed.
Lab-grown: Pink-red and orange lab-grown diamonds are becoming available but are not yet common. They do not compare in rarity or value to naturals.
Value & Investment
Red and orange diamonds represent the absolute peak of gemstone value per carat. Natural red diamonds consistently sell for $1–2 million per carat or more at auction. Natural Fancy Vivid Orange diamonds can exceed $2 million per carat for exceptional stones.
These are purely collector and museum-grade stones. If a “red diamond” is being offered at an accessible price, it is almost certainly a treated stone or a deeply saturated pink that has been commercially described as red.
Buying Tips
- For natural red or orange diamonds, GIA certification is non-negotiable.
- Be extremely cautious of red diamonds offered without major lab reports — natural reds are museum-grade rarities.
- Orange diamonds with brownish or yellowish modifiers are more available and significantly more affordable than pure oranges.
- For the orange diamond look at an accessible price, consider lab-grown options or orange spinel and garnet alternatives.
Explore more colors in our Colored Diamond Guide.