Koh-I-Noor
Koh-I-Noor Historic Cut
Koh-I-Noor Modern Cut
Specifications of Historic Cut
| Weight | Approx. 189 carats* |
|---|---|
| Dimensions | 41.74 x 33.89 x 16.68 mm** |
| Color | Colorless |
| Weight of Rough | Unknown |
| Origin | Golconda, India |
| Date Found | Unknown; possibly as early as the 1300’s |
| Current Location | Tower of London; British Crown Jewels |
*The historic version was cut into the modern 105.6 carat oval.
**Derived from photos of the plaster cast of the historic cut that resides in the Natural History Museum of London.
Details
The Koh-I-Noor: A Diamond's Resurrection
Of all the world’s legendary diamonds, few inspire such fascination—or controversy—as the Koh-I-Noor. Its path through history is long and contested, but its transformation from a 186-carat Mogul-cut stone to the 105-carat oval gem we see today in the British Crown Jewels is a story of both empire and craftsmanship.
For over two decades, Scott had dreamt of recreating the Koh-I-Noor in its original form. He first began the research in the 1980s, but reliable source material was scarce, and the technology needed to do the stone justice simply didn’t exist. It wasn’t until a call in 2005 from fellow stonecutter Dale Carriere that the project truly took flight.
Bauer’s Koh-I-Noor Drawing (side view)
With Dale flying in from California, the two spent an intensive weekend photographing and analyzing the model. Using a Mirror Facet lap, they reverse-engineered the facet structure, assisted by Steve Attaway, who created wax models from their reference data. But discrepancies soon appeared—particularly between the glass model and a historical drawing by Bauer. They needed a tie-breaker: something authoritative, objective, and historically grounded.
That source came in the form of two original plaster casts, created just before the 1852 recut and housed at the Natural History Museum in London. With the museum’s cooperation, one cast was shipped to them for study. Over another intensive weekend, Scott and Dale captured hundreds of photographs, allowing them to produce detailed line drawings and begin accurate 3D modeling.
Then came the surprises.
Typical rough spot on KIN plaster cast
Dieulafait’s drawing
Surface “defects” noted on both the glass and plaster models—previously dismissed as casting errors—were confirmed to be real. They corresponded exactly across both casts. These were not signs of damage or poor workmanship, but genuine features of the original diamond. They may have been misunderstood as cleaved damage inflicted before the British acquired the stone, but closer analysis showed otherwise: smooth, rounded indentations, not the sharp, brittle edges of cleavage planes.
With physical modeling in full swing, the plaster model was sent to Belgium in 2007 for laser and X-ray scanning. Using the latest in gemological scanning and modeling technology, the diamond’s original surface topology was digitized. The result? A 169-facet recreation of the historic Koh-I-Noor, rendered in cubic zirconia (CZ). It was the most accurate physical representation ever created of the legendary original.
Photo by Scott Sucher
But history wasn’t finished with them yet.
Later that year, while visiting the Natural History Museum for the opening of The Vault exhibit, Scott and his wife Karen were invited into the museum’s research room. There, hidden from public view for over a century, was a blue velvet stand with four brass posts. To any other visitor, it may have seemed unremarkable. But to them, it looked like the original 1851 exhibition stand used to display the Koh-I-Noor at the Great Exhibition.
They had one way to prove it.
Without missing a beat, Karen pulled their CZ replica from her backpack. Scott placed it between the posts—and it fit perfectly. Snapped into place like it had always belonged there. The fit was absolute. A quiet moment of joy and validation followed: after years of effort, they had found the original cradle for one of the world’s most iconic stones.
The project didn’t just produce a replica—it corrected the record.
Using a special GemCad utility, Scott was able to model both the historic and modern stones and analyze their relationship. The data proved something important: despite criticism, the team at Coster Diamonds had done the best possible job with the constraints they facet—shape, yield, and flawed rough. The 1852 recut wasn’t poorly done, but the highest expression of the diamond-cutting art in its time.
The story continued into 2009 when Aymeric Peniguet de Stoutz, a historian from France, contacted Scott. He had noticed an inconsistency between Scott’s pavilion pattern of the recut form and a drawing by Tillander (1995). After some digging and a rare book photo from The Crown Jewels, it became clear: Tillander was right. The pavilion had an extra row of facets. Once again, history needed updating. And so, another recut replica began.
What started as a stalled dream eventually led to the most accurate recreation of the original Koh-I-Noor ever made—and in the process, reaffirmed the importance of combining modern tools, international cooperation, and historical curiosity. The Koh-I-Noor may remain in the Crown Jewels, but its original form has finally been brought back to life.