What Does Diamond Cut Mean
Diamond Cut Quality

Few purchases in your lifetime would go beyond the one ring you get for your beloved on your engagement. Picking out the quality and size of the diamond on it can turn into quite the panicky prospect if you let it. All our lives, most of us have been conditioned to believe that when it came to diamonds, “bigger” is always the same as “better”. As it turns out, this is not the case.

What is Quality?

“Better, not bigger” may seem to go against common-sense, but as it happens, a diamond that is larger in size does not guarantee you better bang for your buck. Quality always traces to the sparkle and fire of the stone no matter what, and both of these things rest on the quality of the cut of the stone. A lot of times you see diamonds cut in ways as to maximize weight or carat size, easily sacrificing beauty into the bargain.

Diamond Cut Quality

What does diamond cut mean to overall quality? Everyone that has ever inquired knows of the 4C’s and what they entail for a diamond’s worth on the market. Of these, and according to GIA, “Cut quality is the factor that fuels a diamond’s fire, sparkle and brilliance. The allure and beauty of a particular diamond depends more on cut quality than anything else.” Craftsmanship in this area decides how well the stone is able to handle light in an optimal manner. Any defects would result in lowered light performance, ultimately affecting the beauty of the diamond, as well as its value.


Diamond cut quality gets appraised at many gem laboratories across the world, leading ones among which are GIA and AGSL. GIA grading gets done only for round brilliant-cut stones, and the system which they use is very broad, based on predefined tables. In this 5-grade system, the best a stone can land is Excellent. AGSL, meanwhile, does advanced ray tracing using computerized methods, during which all optical properties of the stone are measured. The top grade in the 10-grade system which they use is Ideal.

The Diamond Cutter’s Options

Any cutter dealing with a piece of rough (raw diamond) is served with a wide range of undecided options in how he would be able to finish and proportion the diamond to bring out the greatest economic yield. There are a number of things he could do to retain higher weight in the final piece, including cutting very deep, so that a thick girdle gets left behind around the perimeter. This makes the stone look bigger, but does little to optimize light performance (brilliance and fire).

Carat Often Costs More than Cut

Based on the quality and size of the rough, it may be possible for the cutter to charge more, so long as he has cut corners with the cut (no pun intended) and maximized the carat weight or size. This is mainly because in the market, carat is often valued higher than cut. Larger diamonds are often sold for premium prices, particularly if they happen to maintain ‘magic marks’ like 2.00 or even 1.00 carat, instead of simply falling below those thresholds.

The Problem for Consumers

For the consumer, the main issue arises when the cutter’s discrepancies have affected the optics of the stone which they bought. The faceting precision and proportioning of the stone decide how well and how much light gets turned back toward the eye. If the diamond is meant to be the center piece in a highly sentimental engagement ring, then it wouldn’t do to have low diamond cut quality ruining the beauty of the thing. When a diamond is cut to maximize its weight, it generally looks smaller to those cut with beauty primarily in mind—the light may not reach edge-to-edge in the same way. Ideal cut stones also typically look much whiter because of the ambient light being channeled back in a more efficient way, so that some of the stone’s body color gets masked.

The Spread

Sometimes you have diamonds cut to play up the outer dimensions, or what are collectively called the “spread”. This is mainly how big the footprint of the stone is when you view it face-up. If the stone is cut too deep, its spread will be smaller-than-normal. If, on the other hand, it is cut shallow, then the spread would be proportionally larger for its size. It should go without saying that each of these cases would net you sub-optimal proportions, and consequently, bad light performance.

When you have a diamond which is meant to be center attraction on an engagement ring of immense sentimental value, it bears making sure that it looks good from all angles, at least based on what you paid for it. For that reason, it also bears ensuring that you try for high diamond cut quality, and not just a stone that looks big from close up.