In evaluating the four Cs of diamonds, Cut is probably the easiest, because it’s clearly discerned just by looking. Of all the cuts, the most popular is round, or brilliant (sometimes even called diamond cut), developed by Marcel Tolkowsky in 1919. Shop for jewelry in the DC area and you’ll see that the majority of engagement rings for sale sport this cut, though Tolkowsky’s original model has been much evolved. Indeed, the round cut represents about 75 percent of all diamonds sold.
There’s a reason this cut is so popular, and why it’s called “brilliant”: the triangle- and kite-shaped facets—usually 58 of them, 33 on the crown alone—created in the cone shape maximize the light returned through the top of the stone, and, therefore maximize its sparkle. (If you’re wondering why all diamonds are not cut this way, it’s because of preference, yes, but usually the original diamond’s shape simply better lends itself to a fancy cut.) In fact, even Tolkowsky’s original model. Diamond shape can also affect the proportions applied to the brilliant cut, so even in round diamonds, there are variations that can affect grading, as can polish and symmetry. Ask our onsite gemologist at Vienna Pawn and Jewelry on Maple Avenue to explain these variations to you.
On a per carat basis, round diamonds cost more than other cuts, because the demand for them is high and also because in creating a brilliant cut diamond, more of the stone is sacrificed; the price difference is usually 25-35 percent higher than for a fancy cut. For buyers, this means the ability to buy a bigger, if not as brilliant stone, for the money.