The cut of the diamond is perhaps the most important of all C’s as it determines its brilliance. While nature determines the color and clarity of a stone, diamond cut is dependant solely upon the skill of the cutter. A diamond cutter spends years mastering his craft, learning how best to cut a rough diamond to achieve the ultimate cut with the fewest imperfections and the least loss of carat weight. The better the cut, the more valuable the diamond. A good cut gives a diamond its brilliance. The width and depth have an affect on how light travels within the diamond and how much brilliance it will exude.
Shallow cut: Light leaks out of the bottom and sides causing the diamond to appear watery and lose brilliance.
Deep cut:Pavilion is cut too thick and causes light to go straight through the diamond. This makes the diamond appear dark and dull.
For starters, find out what shape she likes. Diamonds come in nine basic shapes. Click on each shape for detailed information.
The majority of diamond engagement rings today are set with round diamonds. Most of the remaining rings are set with the princess cut.
Determining the cut of a diamond extends further than straightforward measurements of the width and depth. Diamond grading laboratories utilize optical measuring devices to create a three-dimensional image of your diamond in order to ascertain its proportions and angles.
Diameter -The width of the stone, measured through the girdle.
Table-The largest facet of a gemstone, located at the top of the stone.
Crown-The top segment of a diamond that extends from the girdle to the table.
Girdle-The outermost edge of the diamond, defining the perimeter of the stone and intersecting the upper and lower sections of the stone. Its purpose is to keep the stone from chipping.
Pavilion-The bottom segment of a diamond, reaching from the girdle to the culet.
Culet-The facet found at the very tip of the gemstone, preferably not visible to the naked eye.
Depth-The length of a diamond, as measured from culet to table.
Polish and symmetry are crucial to the diamond cutting process. Both polish and symmetry are assigned a grade, which appear on the diamond certificate. The polish grade indicates the smoothness of the facets, while the symmetry grade evaluates the alignment of the facets. With poor polish, the surface of a facet can be dulled and may create lackluster, blurry sparkle. With poor symmetry, light can be misdirected as it enters and exits the diamond.
Because cut is so important, several grading methods have been developed to help consumers determine the cut of a particular diamond. In general, these grades are ideal, very good, good, fair and poor.
Diamonds on Fifth uses the measurements from each diamond’s grading report to determine:
Table percentage: The ratio of the largest facet on top of stone to the girdle’s overall diameter. Depth percentage: The ratio of the total height or depth of the diamond to its diameter.
From these proportions, Diamonds on Fifth has assigned each diamond a cut grade. The following are the proportion ranges for each grade of diamond cut:
Cut Grade
Depth %
Table %
Ideal
59.1 - 63
53 -58
Very Good
58.1 - 64
52 – 61
Good
57 – 64.5
51 - 65
Ideal cut: An exquisite and rare cut that reflects nearly all the light that enters the diamond and creates maximum fire and brilliance. “Ideal” for the person who enjoys knowing that he has one of the finest diamonds that money can buy.
Very good cut: Reflects almost as much light as the ideal cut but for a lower price. A Diamonds on Fifth recommended buy.
Good cut: Reflects most of the light that enters the diamond. The cutter has chosen to create the largest possible diamond from the original rough crystal, rather than cutting extra weight off to create a smaller but higher quality diamond. Diamonds in this range offer an excellent cost-savings to customers who want to stay in a budget without sacrificing quality or beauty.
Fair cut: A fair cut diamond will not be as brilliant as a good cut, but is still considered a quality diamond.
Poor cut: This includes all diamonds that do not meet the performance standards of a fair cut. These diamonds are deep and narrow or shallow and wide and tend to lose most of the light out the sides and bottom. Diamonds on fifth does not carry diamonds with cut grades of poor.
Diamonds on Fifth carries an exquisite selection of certified ideal-cut diamonds. We do not carry diamonds with cut grades lower than good as these are generally too shallow or too deep to present an acceptable amount of brilliance.
Diamonds on Fifth Recommendations While a good quality round diamond with an ideal cut will certainly be very beautiful, very good and good cuts might be just as attractive without costing as much. Diamonds on Fifth recommends that for fancy shapes, good and very good cut grades will result in the best performance. Consider the length to width ratio of the diamond and the design of the mounting when selecting a fancy shape.
