Jewelry Education
Cut
People often make the mistake of referring to the shape of a diamond as the cut (round diamonds, princess cut diamonds, marquise cut diamonds, oval diamonds, pear-shaped diamonds, emerald cut diamonds, radiant cut diamonds, heart-shaped and asscher cut diamonds). But cut really is the craftsmanship applied in cutting the facets of the stone. The artisan attempts to cut a diamond to make the best use of light.
The cut or "make" is the arrangement of the facets of a diamond, known as its proportions, and a byproduct of the cutter's expertise in finishing and polishing the stone. Complex mathematical formulas are used to achieve the beauty and reflection of a diamond, known as its brilliance. There are many measurements that go into creating a diamond that truly maximize the refraction of light. Facets must be cut at exactly the right angles relative to one another; the top and bottom halves of the stone must have the proper depth relative to each other; the table, or flat surface on the top, must be the correct size, relative to the overall size of the stone. And, of course, the facets on the top (crown) and bottom (pavilion) must align correctly with each other.
Cut is extremely important in evaluating the quality of a diamond because a well-cut diamond will produce the ultimate in luster and beauty, while a poorly cut diamond will actually lose light and appear dull.
Well Cut
When a round brilliant diamond is properly cut by a master cutter, it is a splendor to behold. Although the consensus among
buyers varies, as with personal taste, if it is properly cut, a diamond will reveal total planned light reflection. When a
diamond is cut to good proportions, light is refracted from one facet to another, and then dispersed through the top of the
diamond.
Too Deep
When a diamond is cut too deep, the light entering the stone it passes from one side of the bottom to its opposite side, and
leaks out the bottom. The steep angle doesn't allow the light to be returned to the top, and results in unplanned light
leakage. When looking at the diamond from the top, the center of the stone appears dark because of lost brilliance.
Too Shallow
When a diamond is cut too shallow, the light entering the top of the stone passes directly through the bottom of the stone
without any attempt to be returned to the top. The shallow angle doesn't allow the light to be returned to the top, and this
light leakage also affects the brilliance. When looking at the diamond from the top, the diamond appears watery and glassy.
Ultimately, cut determines the beauty that is manifested in a diamond. A well cut diamond sparkles more, has more fire, and offers the greatest brilliance. In contrast, if a stone is cut poorly it will appear less valuable because it will lack fire, scintillation, brilliance and therefore, beauty.
