Raw Diamonds: What Are Raw or Rough Diamonds?

Why We Need the “Raw” or “Rough” for a Diamond

Raw or rough diamonds look quite different from polished and cut diamonds. An expert diamond cutter studies diamond rough carefully before cutting. During the cutting process, undesirable clarity characteristics might be cut away to increase the diamond’s value. With very few exceptions,diamonds aren’t very attractive in their rough state. Rough diamond crystals have irregular surfaces that conceal the stone’s wonderful optical qualities: only with expert cutting and polishing do a diamond’s scintillation, brilliance, and fire, appear in all their beauty.

How Do You Identify a Raw Diamond?

A raw or rough diamond is a crystal, so you can find a rough diamond in any number of shapes, including octahedrons (eight sides), cubes (six sides), and dodecahedron (twelve sides). Its surface is not polished nor faceted, so it will lack fire and scintillation. Unlike raw mined diamonds, lab-grown raw diamonds will all come in cubic form.

What’s the Difference Between Raw Diamonds and Polished Diamonds?

If you ever saw a raw diamond and a polished diamond side by side, you’d be surprised that they actually share identical physical and chemical properties. After an expert diamond cutter cuts, facets, and polishes the raw diamond, the diamond is then ready to be cast in a setting. Polished diamonds come in a variety of standardized shapes, including Round, Oval, Pear, Marquise, Emerald, Asscher, Cushion, Radiant, and Princess Cut. In addition, you lose a considerable amount of carat weight when you cut and polish a raw diamond: the famed Hope diamond, for example, had a rough carat weight of 110.50 carats, while the modern-cut weight is 45.52 cts.

Does A Raw Diamond Influence The Cut and Shape of a Polished Diamond?

Yes, the shape of a raw diamond does influence the way it can be ultimately cut and shaped, and this is especially true in mined diamonds. Octahedrons (crystals with eight triangular facets, with the widest at the center, resembling a spinning top) with a rounder shape will generally be cut into two Round Brilliant diamonds. Broken octahedrons or dodecahedrons (a crystal with twelve facets) usually just yield one stone when properly cut and polished. Finally, there are also irregularly shaped raw diamonds that require special care when being cut, and whose polished form will depend on the original shape of the rough diamond. Emeralds and Radiants can be fashioned from odd-shaped raw diamonds.

Are Raw Diamonds Graded?

The grading report that includes the 4Cs only relates to the cut and polished final product, because parameters like cut and symmetry involve both the characteristics of the stone and the mastery of the craftspeople involved in the cutting and the polishing process. Usually over 1/2 of the rough diamond is lost during the cutting process, which obviously impacts the carat weight. In addition, when a rough diamond is cut and polished, it is possible to work around some of the most visible inclusions and clarity characteristics of the rough diamond.

“The clarity of the final diamond of course depends on the clarity of the rough, but it gets assessed to ensure the fewest possible large inclusions are present based on the shape selected,” explains Grace Taylor, VRAI’s Director of Sales and Customer Experience. “Color and clarity really aren't able to be assessed at all until the diamond is polished (at least rudimentarily)”.

How Is a Lab-Grown Raw Diamond Made?

Lab-grown diamonds are physically identical to mined diamonds, and this extends to raw, VRAI created diamonds as well. The only difference between the two is point of origin Lab-created diamonds share an identical growing process to mined diamonds. They form first as carbon atoms under high temperature and immense pressure, then bond together to grow a crystalline lattice structure. “A lab grown rough grows in a cubic shape while a naturally mined one will grow in an octahedron shape –think two pyramids put together at their widest end,” explains Taylor. “This is one of the only times there is any type of visual difference between a lab-grown and natural diamond and is a result of the growth process.”

Can I Purchase a Raw Diamond?

You can purchase a Raw Diamond, but not at VRAI. You can, however, choose to have a VRAI created diamond cut-to-order in your preferred cut (rose cut, brilliant cut, step cut, mixed cut) and shape out of 30 possible options. These include in-house cuts such as the Fusion cut, which combines Oval and Emerald faceting, the Harmonia, a Round Brilliant with added faceting, and step cuts such as the Hexagon cut and the Lozenge cut.

“For Cut for You diamonds we use a system called Sarine Advisor which takes a 3d model of the diamond block and a map of its natural inclusions and charts the diamond shape with the best possible cut (while simultaneously avoiding as many inclusions as possible),” explains Taylor. Don’t worry, customers won’t choose their own rough block. “Our master cutters will select it for them based on the size and shape they want and the results from Sarine Advisor on our various available rough blocks.”

Unlike pre-cut diamonds, which are limited to the available shapes and carat weights in-stock , VRAI now offers the option to choose from 31 unique diamond shapes and in larger carat weights, even if they are not currently in VRAI’s existing in-stock inventory.

Learn about Diamonds With Our Experts

If you’re ever curious about the origin and creation process of VRAI created diamonds, our experts are always ready and eager to answer any questions you might have.