What is Diamond Depth and Table? | Ideal Size & Percentages

What is Diamond Depth and Table? | Ideal Size & Percentages

What is Diamond Depth and Table? | Ideal Size & Percentages

Posted by Sharif Khan on 2nd Aug 2022

Diamond Depth and Table

About Diamond Depth and Table

When shopping for a diamond, you should consider some factors before honing in on your ideal stone. Most of them broadly fall under what experts call the  Four Cs of diamonds: cut, color, clarity, and carat weight. Each of these factors impacts the aesthetic appeal and price of a diamond. 

Diamonds are measured in carats, with one carat equaling 0.2 grams or 0.007 ounces. Therefore, diamonds of a higher carat weight are costlier than those that weigh less, provided all the other factors remain constant.

Besides the  carat weight, diamonds also come in numerous color hues. In terms of diamond color, the general pricing rule is that the more colorless the appearance of a stone, the costlier it will be. However, there's an exception to it when it comes to red and pink diamonds.

Clarity refers to the number of visible inclusions or blemishes a diamond possesses that are responsible for its appearance. This connotes that the more imperfections in a diamond, the lower the cost compared to its flawless counterpart.

Blue Nile

The last element of the four Cs is the cut. As you shall find, one can come across many diamond cuts. Moreover, contrary to popular perception, the  cut of a diamond isn't the same as its shape. Instead, it refers to a seamless combination of the diamond's proportions, polish, and symmetry and how it (the combination) affects the overall aesthetic appeal of the stone. For instance, round diamond cuts are not necessarily round in shape.

Diamond Depth

What is Diamond Depth?

Out of the four Cs we discussed, shoppers often pay more attention to the cut of a diamond. This happens because of the significant effect a diamond cut has on the stone's overall appearance.

The cut of a diamond affects the appearance of the stone in three fundamental ways. These include:

  • Brilliance: The measure of the brightness of both reflected and refracted lights;
  • Fire: How a diamond disperses light into various flashes of visible color; and
  • Scintillation: How a diamond sparkles when you move it.

It is pertinent to note that the depth of a diamond plays a pivotal role in determining its brilliance, fire, and scintillation. Depth, in this case, is defined as the height of the stone as measured from the culet to the table, usually in millimeters.

The culet of a diamond refers to the bottom tip of the stone. Being the bottom-most facet, it is impossible to be seen with the naked eye. Therefore, an ideal culet is usually graded as either "small" or "none." On the other hand, the table of a diamond refers to the topmost facet of the stone and is regarded as the largest one.

As we've already indicated, the depth of a diamond plays a significant role in influencing how light travels through it. It also determines the amount of light that reflects on the observer's eye.

For instance, light often travels significantly fast in shallow diamond cuts before leaving via the pavilion without creating any reflections. But, when the cut is too deep, the diamond may have poor sparkle, causing it to appear deceptively smaller. This underscores the importance of choosing a diamond of an ideal depth. With the right depth, a diamond should let in as much light as possible. The light should hit each pavilion facet at an angle so that most of it reflects back to the observer's eye.

James Allen

What is The Ideal Diamond Depth?

Right off the bat, it's important to remember that the ideal depth of a diamond varies depending on the shape and cut of the stone. The depths are usually graded from Poor to Excellent.

Since depth is crucial in determining a diamond's aesthetic appeal and light performance, it is usually captured on a diamond grading report. In the report, you'll spot two different measurements described as diamond depth.

The first measurement, expressed in millimeters, refers to the total height of the diamond, while the second has to do with its depth percentage.

Ideal Diamond Depth Percentages

To calculate the depth percentage of a diamond, you should divide the total height by the average diameter of the stone and multiply the answer by 100. If a diamond's average diameter is 10 millimeters and the stone has a total height of 6 millimeters, you will arrive at the depth percentage as follows:

> (Total Height/Average Diameter) x 100.

> Divide 6 by 10, which gives you 0.6 millimeters.

> Multiply 0.6 by 100, which gives you 60%.

While there are no ideal diamond depths, certain recommended depth ranges might guide you as you shop for a suitable gem. The following are the ideal diamond depth ranges for the popular diamond shapes:

Escher or Emerald-cut diamonds From 61 to 68
Cushion cut diamonds From 61 to 68
Heart-shaped diamonds From 56 to 62
Marquise diamonds From 58 to 62
Oval cut diamonds Less than 68
Pear-shape diamonds Less than 68
Princess cut diamonds From 68 to 75
Radiant cut diamonds Less than 67
Round diamonds From 59 to 62.6

As highlighted before, the depth of a diamond is crucial in helping customers grab hold of the best diamonds. But how do you leverage this critical aspect while shopping for your dream gemstone?

First, you would need to determine the diamond cut that you desire. For instance, if you are looking for a round diamond, request the vendor to produce a few round diamonds that fit the description of your preferred stone. Afterward, visually examine the diamonds to ensure they possess the physical characteristics you want.

Of the Four Cs, you will discover that the cut is the most challenging aspect to determine. To ascertain that you get the right diamond cut, ask for a diamond grading report from the seller. Now, look for the depth percentage assigned to your desired round diamond. If, after thoroughly reading it, you realize that the depth percentage is between 59 and 62.6%, you can confidently claim that the diamond has been perfectly cut and faceted. On the other hand, a depth percentage score outside the recommended range means the diamond has not been well-faceted, which may bear upon the stone's sparkle and brilliance.

Diamond Table

What is a Diamond Table?

A diamond table is the flat, topmost, square-shaped facet of a diamond and is so named due to its crucial position and role in the diamond structure.

The fundamental function of a diamond table is to refract the rays of light that pass through the diamond and direct them to the different facets. Similar to the depth, a diamond table also defines a diamond's fire, brilliance, and scintillation, depending on how it handles the light that enters the stone.

The size of a diamond's table is one of the crucial factors affecting its appearance. There is a common misconception that the bigger a diamond table is, the more efficient it can prove at handling light. However, bigger diamond tables do not necessarily translate to better light-handling properties. If a diamond table is too large, its upper facets may not have sufficient room to disperse light. Similarly, if the table is too small, minimal light will penetrate through the diamond, diminishing its brilliance.


What’s The Ideal Diamond Table Size?

Naturally, you would expect larger diamonds to have proportionately larger table sizes and higher table percentages. But depending on how the diamond is cut and faceted, the table size may not always be relative to the entire stone. In most cases, consumers must choose between fire and brilliance when deciding the suitable table size for their diamonds.

Due to the variance in the physical size of diamond tables, jewelers usually rely on the table percentages when grading their diamonds instead of the table size. Hence, on the diamond grading report, the table size is assigned a score between Poor and Excellent, while the table percentages are indicated in numbers.

Ideal Diamond Table Percentage

According to the American Gem Society, the ideal table percentage of a diamond should range between 52 and 62%. But, as you will soon know, those percentages come down to individual preferences. Also, an ideal table percentage depends on the overall size and shape of the stone.

A diamond table percentage is determined by dividing the table's overall width by that of the whole diamond and expressing the answer in percentage. For instance, if a diamond has a table width of 10 millimeters and a total width of 8 millimeters, you will arrive at the table percentage as follows:

> (Table Width/Total Width) x 100

> 10/8 = 0.8

> 0.8 x 100 = 80%

The table below illustrates the ideal diamond table ranges depending on the cut;

Escher cut diamonds 61 - 69
Cushion cut diamonds 61 - 67
Emerald cut diamonds 61 - 69
Heart-shaped diamonds 53 - 63
Marquise shape diamonds 53 - 63
Oval diamonds 53 - 63
Pear-shaped diamonds 53 - 63
Princess cut diamonds 67 - 72
Radiant diamonds 61 - 69
Round diamonds 53 - 58

Reading from the table above, the numbers do not appear to vary significantly. However, those minor variances exponentially affect a diamond's overall brightness and appearance. Similar to a diamond's depth, understanding the ideal table percentage for a cut is invaluable when shopping for a gemstone.

How to Choose the Perfect Depth and Table Sizes for Your Diamond?

Please remember that out of the Four Cs, the diamond cut is the most difficult aspect to analyze because what appears round to the naked eye may be oval. Besides, even if you are astute enough to distinguish between different diamond shapes and cuts, you may not be able to analyze the technical details relating to a stone's facets. Such challenges were the inspiration behind the invention of depth and table percentages.

As a consumer, the first thing to ensure is that the diamond you buy is accompanied by a grading report from a  reputable diamond grading lab. Finding a diamond's grading report should not be a problem since diamonds certified by renowned grading labs—such as the Gemological Institute of America and the American Gem Society—often come with reports indicating depth and table percentages. Please go through the report and, before you check the depth and table measurements of the diamond, make sense of its cut grade. Also, though the depth and table percentages are finer aspects of a diamond's cut, you need to ensure that the stone is of your desired cut grade first.

For example, you could be trying to choose between a diamond cut grade of Super Ideal Make and one of Ideal Make. Compared side by side, the diamond-graded Super Ideal Make is superior. However, to compare two diamonds with a cut grade of "Super Ideal Make," you ought to study their depth and table percentages. The stone with a higher depth or table percentage within the ideal range will have better light performance.

One notable benefit of ideal depth and table percentages is that they do not affect your budget significantly. Given that the values are expressed in percentages, they remain constant regardless of your diamond's weight, color, or clarity. Therefore, a diamond weighing 0.5 carats can have a depth or table percentage consistent with another diamond weighing 100 carats. With other factors kept constant, these two stones will have similar light-handling properties.

Why Should You Choose Depth And Table Correctly?

We strongly recommend that you exercise due diligence when choosing a depth and table, as these are the two primary aspects of a diamond's cut that influence its light performance. Collectively, a diamond's depth and table affect the brilliance, fire, scintillation, and luster of a diamond. In simpler terms, they influence how sparkling your diamond is. Since we all know that appearance is the primary consideration when shopping for jewelry, it is essential not to skip this inevitable step.

Another reason for correctly choosing the depth and table is that they  determine the price of a diamond. Please remember that jewelers usually leverage these seemingly trivial details while pricing their diamonds. You may note that two stones that are similar in other aspects come with different price tags depending on their depth and table ratings.

The diamond depth and table measurements are designed to help shoppers hunker down on their ideal stones. However, even if a diamond has values that fall within ideal ranges, you should consider other quality parameters. Above all, remember that your tastes and preferences are the most important. If a diamond appears excellent to your eyes, everything else is secondary.