DIAMOND CUT

Cut can have two different meanings depending on what is being discussed. Some people refer to cut when referring to a diamonds “shape”. For instance, a round brilliant cut or a princess cut. However, when we typically discuss the cut of a diamond we are referring to how well the diamond cutter did his job. Questions regarding the physical faceting, symmetry and polishing are answered when discussing the “cut” of a diamond.

A well cut diamond will return more light to the viewer and appear to be much brighter and more brilliant than a diamond that has been poorly cut. Unfortunately cut is the one factor that most people know nothing about and some jewelers may not discuss it in detail.

At 14 Karat we rely on the Gemological Institute of America (GIA) grading system for cut diagnostics just as we do for color, clarity and carat weight. GIA is the world’s foremost gemological research laboratory and grading institution and in 2006 surprised the diamond community with a new cut grade standard on round brilliant cut diamonds that was 15 years in the making. The new system takes into account more than 70,000 individual grading observations in different lighting conditions, taking into account the diamonds actual specifications and the trained graders perceptions on how the diamond reacted with light. Out of this 38.5 million proportion combinations were calculated!

The system is based on 7 components divided into two categories: Face Up Appearance and Design/Craftsmanship. Face up appearance takes into account a diamond’s brightness, fire and scintillation. The design/craftsmanship category is based around a diamonds weight ratio, durability, polish and symmetry.

BRIGHTNESS = Is primarily impacted by a diamonds cut and is the visual effect of white light internally and externally. A well cut diamond can be brighter than one with a higher color grade!

FIRE = Is the visual effect of the white light being separated into colored light (like a rainbow) as the diamond is like a color prism.

SCINTILLATION = The difference between light and dark and the sparkle that results as the diamond is turned or the viewer moves. Sometimes people will refer to the “flash” they receive when moving a diamond back in forth in light.

POLISH = The polish of a diamond is important because it is one of the “finish” grades along with symmetry. When grading polish, the grader will look for minor blemishes on the diamond caused by excessive heat during cutting, abraded culets and facets junctions. Polishing lines may also be present which are caused by extremely small pieces of diamond being dragged across the stone during cutting. At 14 Karat we strive to have all our round diamonds earn a “Very Good” or “Excellent” rating from GIA. In the fancy shapes we insist on at least a “Good” or higher rating. We do not sell any diamond with less than a “Good” rating.

In the fancy shapes we insist on at least a “Good” or higher rating. We do not sell any diamond with less than a “Good” rating.

SYMMETRY = Does not refer to how “round” a diamond is. Instead it refers to how well the diamond cutter was able to align all the facet junctions on a diamond. The degree of inaccuracy is measured and used to calculate the symmetry grade. A diamond that is extremely accurately aligned will transmit and use light much more efficiently therefore generate more light to the viewer. Symmetry is an extremely important factor when determining the cut grade on a diamond as it shines a light on how well the cutter actually was able to transform the stone. As with polish, we are extremely particular and a “Very Good” or “Excellent” grade is common on our round diamonds. We do not sell any diamond with lower than a “Good” rating in either round or fancy shape diamonds.

After taking in all of these factors, GIA gives the diamond an overall cut grade which appears below. It should be noted that at this time GIA only gives a cut grade rating to round brilliant cut diamonds. They have not released any data at this time concerning princess cuts or the other fancy shapes.

For those who are curious, the top cut grade in a round diamond that you can purchase at this time are the so-called “Triple EX” grade diamonds. These diamond have an overall cut grade of “Excellent”, a polish rating of “Excellent” and a symmetry rating of “Excellent”. These diamonds make up a fraction of round diamonds cut and can command as much as 8-12% more than a non-triple EX diamond. However, for those who want the best possible, this is it! GIA does not use the term “Ideal Cut” to refer to any round brilliant cut diamond.

WE RECOMMEND:

With round diamonds we recommend that the diamond achieve a “Very Good” or “Excellent” overall cut grade. With princess cut and other fancy shapes, a rating of at least “Good” or higher is mandatory on polish and symmetry, with “Very Good” being more common. At 14 Karat we are very particular with the overall cut grade of each diamond that leaves our store. We do not buy massive bulk parcels of diamonds but instead “cherry pick” those that meet our expectations. We pay a higher price for doing business with our suppliers this way, but it provides you, the customer, with the highest quality diamond. In addition, we always stand by our pledge to find exactly what you are looking for no matter if it is not in stock at no additional price.