A rough diamond removed from the earth or a growth chamber is not beautiful. It is an octahedral crystal of carbon — transparent or translucent, with flat faces and sharp edges, resembling a pale geometric mineral more than the object that will eventually sit in a ring. What transforms it is cutting: the precise removal of material according to angles calculated to redirect light. The history of gemstone cutting is the history of understanding how light moves through transparent material — and how human ingenuity learned to control it.
Every diamond shape in existence today is a response to a specific problem: how to make the most of what light does when it enters a stone. The oval, the pear, the cushion, the emerald cut — each one is the result of centuries of accumulated knowledge about geometry, optics, and the relationship between the two.
The ancient period: abrasion and the point cut
The two oldest approaches to gemstone presentation: the smooth cabochon, which emphasises colour and depth, and the point cut, which introduced the first faceted light return in diamond.
For most of human history, gemstones were not cut at all. They were polished — abraded against harder materials to smooth their natural surfaces and reveal their colour. Rubies, sapphires, and emeralds were shaped into cabochons: smooth, domed forms with flat backs, polished to bring out colour and translucency without the faceting that produces brilliance. The cabochon is the oldest gemstone form in continuous use; it predates faceting by several thousand years and remains the correct cut for certain stones today, particularly those with optical phenomena like asterism (the star effect in star sapphires) or chatoyancy (the cat’s eye effect in chrysoberyl).
Diamond presented a different challenge. Its hardness — 10 on the Mohs scale, harder than every other natural material — meant that the abrasive techniques used for coloured stones were ineffective. Diamond can only be cut by diamond. The discovery that diamond powder could be used to abrade and polish diamond itself was the prerequisite for all diamond cutting that followed.
The earliest diamond cutting produced what is called the point cut: the natural octahedral crystal of a rough diamond, simply polished on its existing faces without removing material. The point cut retained the crystal’s natural geometry and produced a modest play of light. It was the dominant diamond form in medieval European jewellery, appearing in the rings and brooches of nobility from approximately the thirteenth to the fifteenth centuries.
The table cut and the emergence of faceting
The table cut, developed in the fifteenth century, was the first deliberate departure from the crystal’s natural form. It involved removing the top point of the octahedron to create a flat upper surface — the table — while keeping the lower half of the crystal as the pavilion. The result was a stone with a large flat face that caught light differently from the natural point: more directly, more visibly, more legibly as a jewel.
The table cut introduced the principle that would drive all subsequent development: that the geometry of the facets, not the natural geometry of the crystal, determined how light behaved inside the stone. Once cutters understood that they could control the angles, the question became which angles produced the most desirable effects.
Through the sixteenth and seventeenth centuries, the number of facets multiplied. The rose cut — a domed stone with triangular facets rising from a flat base to a central point — emerged in the mid-sixteenth century and became the dominant diamond form for nearly two hundred years. Rose cuts produce a softer, more diffuse light than modern brilliant cuts; they appear in portraits of the period as points of warm light rather than flashes of fire. Their aesthetic is closer to candlelight than to electric light, which is precisely the context in which they were designed to be seen.
Rose cut and round brilliant: two philosophies of light separated by four centuries. The rose cut was designed for candlelight; the brilliant for the mathematics of optics.
The old mine cut and the birth of the brilliant
The old mine cut and old European cut represent two centuries of incremental refinement — each an attempt to bring more light through a diamond before the geometry was finally calculated, not approximated.
The old mine cut, which emerged in the late seventeenth century and dominated the eighteenth and nineteenth centuries, is the direct predecessor of the modern round brilliant. It has a high crown, a small table, a large culet (the flat point at the very bottom of the stone), and a roughly cushion-shaped outline — because cutters were following the natural crystal shape rather than a mathematically defined round. Old mine cut diamonds appear in Georgian and Victorian jewellery; their optical character is warmer and softer than a modern brilliant, with a different distribution of light and shadow that many collectors find more appealing.
The old European cut, which followed in the latter half of the nineteenth century, brought the outline closer to round and increased the number of facets, but retained the high crown and small table of the old mine cut. It was the dominant diamond form until the early twentieth century and remains one of the most sought-after cuts in the antique and estate jewellery market.
The modern round brilliant cut was defined mathematically in 1919 by Marcel Tolkowsky, a Belgian engineer and diamond cutter who published a treatise calculating the ideal proportions to maximise both brilliance (white light return) and fire (dispersion of light into spectral colours) simultaneously. Tolkowsky’s analysis specified crown angle, table size, pavilion depth, and culet diameter as interdependent variables — a system rather than a convention. The 58-facet round brilliant that resulted has been the dominant diamond cut ever since, and it is the form against which all other cuts are evaluated.
Marcel Tolkowsky’s 1919 treatise defined crown angle, pavilion depth, and table size as an interdependent system. A century later, laser-precision cutting refines the same proportions — the theory unchanged, the execution perfected.
The fancy cuts: each shape solves a different problem
Every non-round diamond shape is called a fancy cut. Each one emerged from a specific challenge: how to retain carat weight from a particular rough crystal shape, how to achieve a certain visual proportion, or how to produce an optical character distinct from the round brilliant.
The oval cut was developed by Lazare Kaplan in 1957 as a way to cut elongated rough crystals without sacrificing weight to achieve a round outline. The oval produces the same optical performance as a round brilliant — it has the same facet structure — but its elongated outline makes the finger appear longer and allows the stone to appear larger face-up than a round of equivalent carat weight. The DHARIN Oval Solitaire Ring uses this cut precisely for those reasons: maximum optical performance, elongated proportion, maximum apparent size on the hand.
The emerald cut was developed not for diamonds but for emeralds. Emerald’s internal fractures — the jardin that makes most natural emeralds included — made it vulnerable to the stress of pointed corners. The emerald cut’s cropped corners distribute stress away from the edges, protecting the stone during setting and wear. Applied to diamond, the emerald cut produces a fundamentally different optical character from the brilliant: instead of dispersed fire, it produces long, rectangular flashes — what the trade calls the “hall of mirrors” effect. The DHARIN Mixed-Cut Tennis Bracelet alternates round brilliants with emerald cuts precisely because the contrast between dispersed fire and linear flash creates a rhythm that neither cut produces alone.
The pear cut combines the pointed end of a marquise with the round end of an oval, producing a teardrop form. It elongates the finger at the pointed end and concentrates brilliance at the rounded end. The pear has been in continuous use since the fifteenth century, when Flemish polisher Lodewyk van Berquem — who is credited with introducing the use of a polishing wheel with diamond dust — is said to have cut one of the earliest examples. The DHARIN Sapphire and Emerald Teardrop Pendant uses the pear form in cultivated gemstone: the point suspended downward, the rounded end at the top, the drop moving with the body.
The round brilliant remains the most optically efficient diamond shape: the most light returned, the most fire dispersed, the most mathematical precision applied to a single stone. It is the cut used in the Classic Diamond Tennis Bracelet, the Diamond Solitaire Studs, the Pavé Eternity Band, and the continuous-line cultivated gemstone tennis bracelets — because for stones set in sequence, uniformity of cut is as important as uniformity of colour.
What CVD changes — and what it does not
Chemical Vapour Deposition grows diamond carbon atom by carbon atom on a seed crystal in a controlled chamber. The resulting rough crystal has the same structure as a mined diamond — the same cubic lattice, the same hardness, the same optical constants. It is cut using the same techniques, on the same equipment, by the same cutters, to the same angle specifications.
What CVD changes is the rough crystal’s shape. Mined diamonds arrive as natural octahedra with irregular inclusions and surface features that influenced historical cut development — the reason early cutters followed the crystal’s natural geometry was that departing from it meant losing weight, and weight meant value. CVD rough can be grown closer to the desired finished shape, which reduces the weight lost to cutting and allows more consistent proportioning across stones of the same specification.
The optical result is identical. A CVD round brilliant at Excellent cut grade returns light in exactly the same pattern as a mined round brilliant at Excellent cut grade — because the angles are the same, the refractive index is the same, and light does not distinguish between carbon atoms formed over a billion years underground and carbon atoms deposited over six weeks in a chamber. Tolkowsky’s mathematics apply equally to both.
Every DHARIN diamond is CVD grown, IGI certified, and cut to specification before setting. The cut grade appears on the IGI certificate. The geometry that Tolkowsky calculated in 1919 is the same geometry that determines how light moves through a DHARIN stone in 2026.
Every DHARIN diamond is independently certified by IGI. The cut grade on the certificate is the guarantee that Tolkowsky’s geometry has been applied — not approximated.
