The World’s Most Expensive Diamonds
The Pink Star Diamond
When discussing the most expensive diamonds in the world, the Pink Star Diamond invariably tops the list. This extraordinary gem sold for a record-breaking $71.2 million at a Sotheby’s auction in Hong Kong in 2017, making it the most expensive diamond ever sold at auction. Originally mined by De Beers in Africa in 1999, this remarkable stone weighed 132.5 carats in its rough form before being meticulously cut and polished over a painstaking 20-month period.
What makes the Pink Star so exceptionally valuable is its rare combination of size and color. At 59.60 carats, it’s one of the largest internally flawless fancy vivid pink diamonds ever discovered. Natural colored diamonds are exceedingly rare, with vivid pinks being among the most sought-after. The Pink Star received the highest possible color grading for a pink diamond from the Gemological Institute of America (GIA).
The remarkable coloration in pink diamonds results from a unique deformation in the crystal lattice structure that occurs during the diamond’s formation deep within the Earth. This structural anomaly causes the stone to absorb light differently, resulting in the coveted pink hue. Unlike some colored diamonds where the color is concentrated in patches, the Pink Star exhibits an even distribution of color throughout the stone, further enhancing its value.
The diamond’s impressive oval mixed cut maximizes its natural color and brilliance while maintaining an exceptional clarity grade. This combination of extraordinary size, color intensity, and purity places the Pink Star in a category of its own in the world of precious gemstones. While most of us may never own such a spectacular diamond, lab-created pink diamonds offer a more accessible alternative that captures similar beauty at a fraction of the price.
The journey of the Pink Star from rough stone to record-breaking gem exemplifies the incredible transformation that diamonds undergo. Each cut and polish decision was made with extreme care, considering how to best preserve its size while highlighting its unique color. The result is not just a diamond but a masterpiece of natural beauty and human craftsmanship that stands as the pinnacle of diamond valuation.
The Cullinan Diamond
The Cullinan Diamond holds the distinction of being the largest gem-quality rough diamond ever discovered, weighing an astonishing 3,106 carats (621.2 grams) when it was unearthed at the Premier No.2 mine in Cullinan, South Africa, in 1905. Named after Sir Thomas Cullinan, the mine’s chairman, this extraordinary discovery forever changed diamond history. The uncut diamond was purchased by the Transvaal government and presented to King Edward VII as a birthday gift.
The monarch commissioned Asscher’s Diamond Company in Amsterdam to cleave and polish the stone. This was an unprecedented challenge that required months of study before Joseph Asscher made the first cut. Legend has it that Asscher fainted after successfully striking the diamond. The Cullinan was eventually cut into 9 major stones and 96 smaller brilliants. The two largest pieces, Cullinan I (the Great Star of Africa) at 530.4 carats and Cullinan II (the Second Star of Africa) at 317.4 carats, are now part of the British Crown Jewels.
While it’s difficult to assign a precise monetary value to the Cullinan diamonds, as they are essentially priceless historical artifacts, experts estimate that Cullinan I alone would be worth well over $400 million in today’s market. The diamond’s exceptional clarity, color, and size contribute to its immense value, but its historical significance multiplies this worth exponentially. For those seeking their own piece of diamond history, engagement rings with historical design elements can capture some of this timeless appeal.
The Cullinan I, set in the Sovereign’s Sceptre with Cross, displays exceptional brilliance due to its 74 facets—a number exceeding the standard 58 facets of a round brilliant cut. This additional faceting enhances its light performance, creating a dazzling display that befits its royal status. Meanwhile, Cullinan II, set at the front of the Imperial State Crown, demonstrates the perfect balance between size and brilliance that epitomizes extraordinary diamonds.
The legacy of the Cullinan Diamond extends beyond its physical presence in the Crown Jewels. It represents the pinnacle of natural diamond formation, requiring specific geological conditions and billions of years to create. While we may admire these historic stones from afar, Espling Jewelers offers exquisite diamond pieces that bring similar joy and brilliance to everyday life, carrying on the tradition of celebrating nature’s most perfect gem.
The Hope Diamond
The Hope Diamond stands as perhaps the most famous diamond in the world, renowned not only for its extraordinary beauty but also for its alleged curse. Currently housed in the Smithsonian National Museum of Natural History in Washington, D.C., this 45.52-carat deep-blue diamond is valued at approximately $250 million. Its distinctive steely blue color comes from trace amounts of boron in the diamond’s crystal structure, making it exceptionally rare even among colored diamonds.
The stone’s documented history begins with Jean-Baptiste Tavernier, a French gem merchant who acquired a 112-carat rough blue diamond (believed to be the Hope’s predecessor) from the Kollur mine in India in the 17th century. After passing through the hands of King Louis XIV of France, the diamond disappeared during the French Revolution before resurfacing in London in the 19th century. It was eventually purchased by Henry Philip Hope, from whom it derives its current name.
What adds significantly to the Hope Diamond’s value and mystique is its purported curse. Various owners of the diamond reportedly met tragic fates, including Marie Antoinette, who was beheaded during the French Revolution. While modern science dismisses the curse as coincidence and storytelling, this colorful history has undoubtedly contributed to the diamond’s fame and allure. For those drawn to blue gemstones without the cursed history, bracelets featuring blue sapphires or aquamarines offer a beautiful alternative.
From a gemological perspective, the Hope Diamond is classified as a Type IIb diamond, one of the rarest categories of diamonds. Beyond its famous blue color, the stone exhibits another remarkable property: it glows red when exposed to ultraviolet light and continues to phosphoresce for several seconds after the UV source is removed. This unusual characteristic adds to its scientific value and mystique.
The Hope Diamond’s current cushion antique brilliant cut with faceted girdle and extra facets on the pavilion showcases the stone’s color and brilliance to maximum effect. While the Hope may be beyond reach for most collectors, natural diamonds with unique characteristics can be found at more accessible price points, allowing jewelry enthusiasts to own their own piece of geological wonder. The enduring fascination with the Hope Diamond demonstrates how a stone’s history, color, and quality together create value that transcends its material worth.
The Koh-i-Noor Diamond
The legendary Koh-i-Noor, meaning “Mountain of Light” in Persian, is one of the most controversial and storied diamonds in history. Currently part of the British Crown Jewels and set in the Crown of Queen Elizabeth The Queen Mother, this 105.6-carat diamond is technically priceless due to its historical significance, though insurance valuations place it at well over $400 million. Unlike many of the world’s most expensive diamonds, the Koh-i-Noor’s value derives primarily from its extraordinary history rather than its size or color.
The diamond’s documented history spans centuries and continents, though legends claim it was mentioned in Sanskrit writings dating back to 3000 BCE. It originated in the Golconda mines of India and passed through the hands of various Mughal and Persian rulers before being acquired by the British Empire in 1849 following the annexation of Punjab. The diamond was presented to Queen Victoria and later re-cut from its original 186 carats to improve its brilliance, though many experts believe this significantly diminished its historical integrity.
What makes the Koh-i-Noor particularly unique among famous diamonds is the ongoing controversy surrounding its ownership. India, Pakistan, Afghanistan, and Iran have all made claims for its return, considering it a symbol of their cultural heritage taken during colonial rule. This contentious history adds an intangible dimension to its value that transcends gemological assessment. For those interested in diamonds with clear provenance, ethically sourced natural diamonds provide peace of mind along with beauty.
From a gemological perspective, the Koh-i-Noor is a D-color (colorless) diamond with exceptional clarity. Its current oval brilliant cut showcases its remarkable transparency and fire. The diamond’s journey from its original table cut to its current form reflects changing aesthetic preferences through the centuries. While the Koh-i-Noor represents the pinnacle of diamond history, contemporary wedding bands often incorporate design elements inspired by historical pieces.
The story of the Koh-i-Noor reminds us that diamonds are not merely gemstones but artifacts that carry cultural significance and historical narratives. Though few will ever own a diamond with such provenance, every diamond has its own unique geological story spanning billions of years—a fact that adds depth and meaning to even modest engagement rings and family heirlooms. The diamond’s journey from deep within the Earth to adorning the Crown Jewels mirrors the transformative journey that all diamonds undergo.
Factors That Make Diamonds Expensive
The world’s most expensive diamonds achieve their extraordinary valuations through a combination of exceptional characteristics that go beyond the familiar “Four Cs” (cut, color, clarity, and carat weight). Understanding these factors provides insight into what makes certain diamonds command prices in the tens or even hundreds of millions of dollars.
Natural colored diamonds sit at the apex of diamond valuation, with vivid pinks, blues, and reds commanding the highest prices. These colors occur due to rare structural anomalies or the presence of trace elements during formation. For instance, boron creates blue diamonds like the Hope Diamond, while structural deformation causes pink and red hues. The intensity and purity of color dramatically impact value—a fancy vivid pink diamond can sell for up to 20 times more than a light pink diamond of the same size and quality. While natural colored diamonds remain exclusive investments, lab diamond jewelry offers vibrant colored options at more accessible price points.
Size remains a crucial factor in diamond valuation, but its impact grows exponentially rather than linearly. A 10-carat diamond doesn’t cost merely ten times more than a 1-carat diamond—it may be valued at 100 times more due to the extreme rarity of large, gem-quality diamonds. This exponential value increase explains why diamonds like the Pink Star command such astronomical prices. The world’s largest diamonds often come from specific mines known for producing exceptional stones, adding a geographical premium to their value.
Historical provenance creates value that transcends physical characteristics. Diamonds previously owned by royalty, celebrities, or historical figures—or those with compelling stories—command significant premiums. The Koh-i-Noor and Hope Diamond exemplify how history and legend can elevate a diamond beyond its gemological worth. Similarly, though on a more accessible scale, estate earrings carry their own histories and craftsmanship from earlier eras.
Perfect clarity becomes increasingly valuable as diamond size increases. While inclusion-free small diamonds are relatively common, finding flawless specimens in larger sizes is exceedingly rare. Many of the world’s most expensive diamonds achieve Internally Flawless (IF) or Flawless (FL) grades, indicating no visible inclusions even under 10x magnification. Beyond standard grading criteria, certain diamonds possess unique optical properties like exceptional light performance or rare fluorescence patterns that further enhance their value. For buyers seeking exceptional quality in their own jewelry collections, Espling Jewelers offers guidance in selecting diamonds with optimal clarity characteristics for any budget.
Investing in High-Value Diamonds
While the world’s most expensive diamonds make headlines when they sell for tens of millions at auction, diamond investing represents a specialized market with unique considerations. Unlike stocks or bonds, diamonds don’t generate income while you own them, and their value appreciation depends on factors beyond simple supply and demand dynamics. However, for those with the knowledge and resources, certain diamonds can prove to be exceptional stores of value over time.
Colored diamonds have consistently outperformed their colorless counterparts as investments over the past two decades. The Fancy Color Research Foundation reports that some categories of natural colored diamonds have appreciated 10-15% annually over extended periods. Pink, blue, and red diamonds have shown particular strength due to their extraordinary rarity and the closure of Australia’s Argyle mine, which produced 90% of the world’s pink diamonds. Serious investors often focus on colored diamonds with GIA certificates confirming natural origin and vivid color intensity. For those interested in colored gemstones at more accessible price points, estate earrings often feature unique colored stones with vintage appeal.
When considering diamonds as investments, provenance and certification take on paramount importance. Diamonds with documented histories from prestigious auction houses like Sotheby’s or Christie’s typically command premium prices and enjoy greater liquidity. Similarly, certification from respected laboratories like the GIA provides essential verification of a diamond’s characteristics. Without proper documentation, even exceptional diamonds may struggle to achieve their full value potential in the secondary market. This emphasis on documentation parallels the importance of choosing engagement rings with proper certification even at consumer price points.
The investment timeframe for diamonds typically extends beyond short-term horizons. Most successful diamond investors maintain holding periods of 10+ years, allowing market appreciation to offset the significant transaction costs associated with buying and selling diamonds. These costs include sales taxes, auction house commissions (often 10-25%), and the substantial bid-ask spread in diamond pricing. Diamonds should generally represent only a small portion of a diversified investment portfolio rather than a primary investment vehicle.
For most consumers, the emotional and aesthetic value of diamonds outweighs their investment potential. Rather than focusing solely on appreciation