Often regarded the “forgotten C”, cut refers literally to the cut of the diamond and all the other workmanship that went along with it in order to bring out  its facets which give it the perfect arrangement of angles best maximizing the stone’s brilliance. An excellent cut is what gives a diamonds its well-known sparkle. The primary explanation behind the cut diamond’s world-renowned brilliance is its high refractive index. Two important phenomena are said to be demonstrated by the diamond’s structure: light bending or refraction and reflectance. These properties are governed by the diamond’s chemical composition, its high density and stiff structure given the crystal’s closely-packed carbon lattice structure. Such structure is said to slow down the velocity of light, as light interacts with the electrons while passes through the crystal lattice. Because of its high refractive index or its adamantine luster, diamonds is used as the standard when it comes to luster of transparent materials (Harlow and American Museum of Natural History 13-15). Nevertheless, the same luster would not be revealed if the diamond remains unfaceted.

            Diamonds are earth’s hidden treasures. Formed under extreme heat and pressure in the transitional zone called moho around 70 miles towards the center of the earth, where the crust and the beginning of the mantle meet, uncut diamonds are anything but dazzling or beautiful in their natural rough forms. After diamonds are expelled into the surface of the earth through the eruption of molten lava, said stones are far from being gems, as they have the appearance of ordinary pebbles. Because diamonds can remain in the soil unnoticed for centuries in their rough form, it is understandable that early civilizations developed jewelry craftsmanship for other gems earlier than they did for diamonds, and that—contrary to modern romanticism for the unequaled gem—diamonds were often used before as mere cutting tools even as polished gems have been symbol of wealth as well. Indeed, a diamond that glitters under the light even if uncut is an unusual find. Therefore, it takes a discerning eye of an expert to know when a dull pebble is in fact a diamond in the rough and it takes a master’s hand to cut and polish such stone to a remarkable sparkle, making an expensive gem out of it.

            Because cut is so essential in bringing out the brilliance of the diamond, good crystallographers or jewelers practically put large amount of effort and focus on cutting the stone so that its facets will reflect the most light. According to Read, cutting a diamond to produce that properly faceted gem requires the expertise of six experts, and this is at least for smaller cutting establishments; in larger settings, more diamond-cutting experts are presumably needed. These experts comprise of the designer, the cleaver and/or sawyer, the bruter, the cross-cutter and the brilliantereer.

            Firstly, the designer prepares the stone for cleaving and cutting. It is the designer one who marks the stone for its proper cutting. Then, the cleaver or the sawyer performs the initial breaking of the stone, after which the bruter creates basic rounded, square, emerald, Asscher oval or marquise shape or profile of the cut diamond. After the bruter’s work, the cross-cutter performs the initial polishing job by grinding the bruted stone’s table, its sixteen main crowns, as well as its pavilion facets and culet. Finally, the cross-cutted stone is passed to the brilliantereer who completes the diamond cutting process, as he grinds the last 24 crowns and 16 pavilion facets. The result after all these procedures is a cut stone with polished facets. In many cutting centers across the world, however, diamond bruting and faceting machines have replaced manual workmanship to reduce costs yet at the same time maintaining that same quality cut and polish for smaller stones.

            In assessing stone cut, the grader compares the angles and proportions of the diamond some master stone with very high brilliance. Diamond cut is graded according to the following scales: 1+/1 (excellent), 2/3 (good), 4 (average), 5/6 (commercial) and 7/8 (irregular). Also, when a diamond is considered to have a “very good” cut, it means that it has exceptional proportion and can reflect back up to 90 percent of the light entering the crystal. When a diamond is considered “ideal”, on the other hand, it is said that it belongs to the rank of the best of round diamonds. Diamonds that are rated as “good” are well-cut and can reflect light quite adequately.  Finally, “fair” and “poor” diamonds have not-so-good proportions but are definitely cheaper than those falling within the former grades. stones.