Diamond Registry

The girdle is the portion of the diamond that connects the top (crown) and bottom (prongs). The girdle provides the shape of the diamond when viewed from the top, and it divides the round top from the pointed bottom when viewed from the side. For round cuts, it’s a very significant component of the diamond since it affects the total cut grade. For elaborate forms, girdle thickness is less of an issue. A girdle is present in all diamonds, however it varies in size and polish. The girdle is responsible for setting and holding diamonds in place, therefore it must be robust and able to tolerate hits to the setting. When you purchase a diamond that has been graded by a certifying organization, it’s like the laser inscription is located on the girdle.

The girdle thickness of a diamond may impact it in a variety of ways, from look to durability. It’s crucial to understand these facts before investing in a diamond.

Carat Weight

For individuals on a strict budget, the impact of girdle width on carat weight will be very important (which, when it comes to engagement rings, is the majority of buyers). A larger carat weight (and hence a higher price tag) will come from a thicker girdle, but the diamond will not seem larger in a setting. Even if the effect on carat weight and price is minor, money is still being spent on something that has no bearing on the stone’s beauty or size. A thicker girdle around the corners of a fancy shape diamond, such as a Marquise, Heart, or Pear cut, might give additional protection against chipping. The most important aspect for diamond purchasers is the carat weight. If you’re looking for the biggest diamond possible, buying a diamond with an exceptionally thick girdle isn’t the greatest option. This is due to the diamond’s extraordinarily thick girdle, which conceals most of its weight. When seen from the top down, a diamond weighing 1.5 carats with an unusually thick girdle and another weighing 1.3 carats with a thin girdle may appear to be the same size. That extra 0.2 carats is probably worth a few hundred dollars, but its girdle wastes it.

Light Return

A diamond’s radiance comes from its high light return. In an ideal world, light enters the diamond and then exits through its table. It disperses as it departs the diamond, giving it the shine that a fine diamond should have. If not cut with proper proportions, a very thick or very thick girdle might have a detrimental influence on light performance. The girdle would be too thick to adequately reflect light back out through the table at the ideal angle. The fisheye effect is caused by light bouncing around inside the stone. A diamond with a very thin girdle might have the same issue, but for different reasons.


Because diamonds are meant to last a lifetime, you should think about their durability before making your purchase. The girdle is one of the features of a diamond that has an influence on its lifespan. Extremely thin girdles compromise the endurance and hence the lifetime of your diamond. While a diamond may last a lifetime, an exceptionally thin girdle creates a narrow edge that is susceptible to chipping over time. If you’re looking at princess cut diamonds, stay away from Extremely Thin and Very Thin girdles; a princess cut already has chippable corners, so adding a thin girdle and corners makes the diamond much more vulnerable to damage. Choose a setting that preserves the diamond, such as a bezel or drill setting, if your diamond has a thin girdle.

Fire and Brilliance

The relative location of the facets that surround a diamond is also affected by the breadth of the girdle. This means that the thickness affects the diamond’s light performance and cut unintentionally. A diamond with an Extremely Thick Girdle will have a lot of brightness and fire, but only if it’s cut well. A thick girdle, on the other hand, concentrates the weight of the diamond in the centre, making the diamond appear smaller when viewed from above. When examining a diamond with a particularly thick girdle, it’s crucial to consider the stone’s entire dimensions. If they’re in the right range, an excessively thick girdle won’t make much of a difference. Remember that the girdle thickness will be evaluated and included into the diamond’s final cut grade. This implies that a diamond can still be considered an Optimum cut and have outstanding fire, brilliance, and scintillation even if the width does not fall within the ideal ranges (Thin – Slightly Thick).


Cut is the most significant of the 4Cs because it affects how light enters and is reflected from a diamond. Symmetry is involved in the relationship between a diamond’s girdle and its cut quality. The GIA assigns a symmetry grade to round cut diamonds based on the precision of their form and the symmetry of their facets, which includes the girdle. The grading method takes into account the average girdle thickness as well as the minimum and maximum widths. They look at the 16 valley places to see how thick they are in comparison to the diamond’s diameter. Although a girdle thickness of either extreme does not inherently imply a lower cut quality, superb and perfect diamonds often have thin to slightly thick girdles.


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