4 Reasons Why Round Cut Diamonds are More Expensive

Sharif Khan
Sharif Khan
Last Updated    EST 
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What first thought comes to mind when you picture a diamond? Hint: It should be something along the lines of bling, and you are about to discover why. Diamonds, especially the rarest ones, rightfully hold the title of being the epitome of precious gemstones. If you are planning to accessorize with diamond jewelry, the least you can do is choose a sparkly gem.

Jewelers, end-users, and casual diamond shoppers conduct significant research before purchasing the ultimate diamond. Jewelers seek the best gem-quality rough stones to cut them into loose diamonds that will maintain their reputation. On the other hand, engagement ring buyers desire an ideal diamond, setting, and post-purchase services.

The pursuit of jewelers to possess the right, in-demand diamond inventories and the desire of shoppers to own an above-average stone boil down to the 4Cs of diamonds. The 4Cs—cut, color, carat weight (ct), and clarity—are the cornerstones of diamond quality.

Depending on your priorities, any of the four Cs can be crucial. However, most shoppers typically prioritize an ideal cut and a sizable stone. Unfortunately, doing so often compromises color and clarity to obtain a nearly exceptional diamond.

The only way to acquire an excellent stone is to purchase a flawless caliber diamond with the highest grades in all 4Cs. But for a round cut, that would come at a considerable cost. Round-shaped diamonds that fall into an average size category (1ct or lower) are expensive. Therefore, you should not purchase an online diamond vendor before acquiring the necessary information.

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Reasons Why Round Cut Diamonds are Expensive

Diamond cutters use two types of raw stones: mined diamonds or human-made ones grown in a laboratory. Either way, the stone is called rough for a reason. It has very little sparkle, if any, in the raw state, is shapeless, and requires extensive polishing.

round cut depth and table

The round cut requires the removal of a significant portion of the rough stone when cutting it into shape. An estimated 60 percent of the raw stone is cut away to achieve a crisp round cut with smooth edges. The portion of the rough diamond crystal chopped off usually ends up as a waste—a by-product.

Developing a round cut leads to losing a significant amount of rough stone compared to the next most expensive cut (princess cut), which only loses about 20 percent.

Using laser-cutting machines, which require extreme skill, does not make much difference. The heavy raw material usage and cutting skills required profoundly impact the price per carat of round cut diamonds.

Of the 4cs, Cut Matters Most

Contrary to conventional wisdom, the shape of a stone does not have anything to do with the cut. If anything, the cut parameters cause the diamond to assume a rounded shape. For the most part, diamond cutters meticulously develop all the proportions of a round cut to achieve a brilliant cut.

ideal cut proportions

A brilliant cut maximizes the diamond’s light performance, meaning a round brilliant cut is one coveted stone. Round diamonds have several cut proportions that line the crown, girdle, and pavilion, each determining the cut grade that a diamond exhibits.

Brilliant round cuts have 57 facets—the various surfaces of a diamond—on the upper and lower body. If the cutter includes a culet (flat face at the bottom of a diamond), the total facet count comes to 58. Brilliant round cuts have the most facets of all diamond shapes, with the highest light reflection and refraction levels.

The GIA grades round cuts into several classes, including (in descending order):

Excellent cut: A perfect round cut is the best cut classification. The stone cut along these lines will possess enormous sparkle and brilliance. The dance of light as it bounces off the facets is impeccable, and there is zero light leakage as it passes through the diamond.

Very Good cut: Tiny light sips from the round diamonds designated the very good cut grade. They have slightly lower fire and sparkle when compared to the excellent cut round stones. A very good round cut is handy when you want to leave more room for color and clarity in your diamond budget.

Good: The round cut is still expensive when cut to good proportions. Round diamonds in this cut grade fly off the shelf the most (around 25 percent of round diamond sales). The good round cut helps to bridge the gap between having the most diamond sparkle and not having to break your wallet.

Poor cut: No cutter in their right mind will go to the length of developing a poor cut round stone. Diamond production is expensive and time-consuming. More importantly, it is a well-respected craft. Unless you are dealing with a quack, you will hardly see a poor cut stone, let alone a poor round cut.

That is because poorly cut stones have the highest light leakage and an out-of-place brilliance due to overly deep or shallow cut proportions. Top vendors like Whiteflash and Brian Garvin do not stock poor cut diamonds.

Round Cut Diamonds Shine the Brightest

You can buy a cut and polished diamond from a vendor or have a jeweler customize one. Assuming you act per the latter option and start with a loose diamond before getting a hand-crafted setting, what C can you maximize? The jeweler or cutter can only maximize the cut or carat weight.

With diamonds, big is not always better. A full-frontal approach towards carat weight will get you a fairly large stone, but you risk it being dull, especially if the cut quality is not the best. Instead, you will be better off ordering a standard-sized stone, 0.5ct to 1ct, with an ideal or excellent cut.

round shape diamond in a swirl engagement ring

But if you cannot afford an excellent round cut, an ideal round cut is the closest you can get to an excellent grade. Besides, ideal round cuts are the highest cut classification in the AGS cut to scale and help to remove excess weight, especially around the diamond’s girdle. An ideal round diamond can reduce the per carat cost without necessarily affecting brilliance and overall appearance.

However, do not confine yourself to this analogy. The bigger and more excellently cut the round diamond, the more prominent the sparkle, fire, and brilliance. A 5ct ideal round cut stone may be smaller than a quarter-dollar coin but still relatively big. If you can afford it, by all means, knock yourself out.

The Popularity of the Round Shape

Diamond vendors sell more round cut diamonds than any other type of diamond cut. According to diamond industry statistics, the majority of diamond engagement rings sold in the US have a round cut center stone.

Round cut stones make up approximately 70-75 percent of ready-to-sell diamonds in the market. It makes sense given that the round cut is one of the earliest developed brilliant cuts, one reason vendors and buyers are fond of it.

Upstream diamond supply chain players (wholesalers and retailers) are always ready to pay a premium price for gem worthy round diamonds. They know that inventory turnover for round cut diamonds is quick whether the stone is loose or mounted on a setting.

In the same vein, the high sales of round cut diamonds mean an ever-surging demand force. It is almost certain that a round cut stone will cost more than any of the other diamond cuts. A round cut stone that has a low 4Cs quality rating can fetch as much as a princess cut stone with an impressive diamond report.

For instance, at James Allen, a 1ct round cut diamond (cut grade: good, color: K, clarity S1) is in the price range of a 1.2ct princess cut stone (cut grade: good, color: K, clarity: VVS2). The point is that the brilliance of round cut diamonds speaks for itself, and as long as the cut quality is not poor, they have more sparkle and fire than other diamond shapes.

The dance of white and colored light in a round cut diamond is intense. When exposed to a light source, it may not be easy to distinguish the stone’s fire from its body color. As a result, round cut diamonds have yet another trick.

The brilliance and sparkle of a round cut stone can hide inclusions in an SI1 or SI2 diamond. Such inclusions, especially tiny dark carbon crystals on the girdle and in the crown close to the table, would otherwise be easily visible to the naked eye.

The diamond development revolution that Marcel Tolkowsky started nearly ten decades ago through the “Diamond Design: A Study of the Reflection and Refraction of Light in Diamond” still lives on today.

Besides, the admiration surrounding the round cut and the proliferation of the modern round brilliant cut are likely to maintain the expensive status of round cut diamonds.

Round cut stones are the diamonds to buy when you want to make a jewelry statement. They are also a priority offering for the shopper looking to buy a diamond with an outstanding sparkle that will last well into the future.