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 16th Mar 2020

Diamond Depth and Table

About Diamond Depth and Table

When shopping for a diamond, there are numerous factors that you should consider before honing in on your ideal stone. Most of those factors broadly fall under what experts refer to as the Four Cs. The  Four Cs of diamonds include the Cut, Color, Clarity, and Carat weight. All of these factors impact the aesthetic appeal as well as the price of a diamond.

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

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

Clarity refers to the number of visible inclusions or blemishes that a diamond has. Inclusions or blemishes mar the appearance of diamonds. Therefore, diamonds with more blemishes tend to cost considerably lower than their flawless counterparts.

The last element of the Four Cs is the cut, and as you shall find, there are many diamond cuts out there. 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 that combination affects the overall aesthetic appeal of the stone. For instance, round diamond cuts aren’t necessarily round in shape.

Diamond Depth

What is a Diamond Depth?

Out of the Four Cs that we’ve just highlighted, it’s the cut of a diamond that shoppers often pay the most attention to. That’s due to the significant effect that a diamond cut has on the overall appearance of the stone.

The cut of a diamond affects the appearance of the stone in three fundamental ways, which include;

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

Now, the depth of a diamond plays a pivotal role in determining the stone’s brilliance, fire, and scintillation. A diamond’s depth is simply defined as the height of the stone, as measured from the culet to the table. It’s usually measured in millimeters.

The culet of a diamond is the bottom tip of the stone. Being the bottom-most facet, it’s impossible to see the culet with the naked eye. As such, the 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. A diamond table also happens to be the largest facet of the stone.

As we’ve already indicated, the depth of a diamond plays a significant role in influencing how light travels through the stone. It particularly determines the amount of light that reflects back to the observer’s eye.

For instance, in shallow diamond cuts, light often travels through the stone considerably fast, before leaving it via the pavilion and without creating any reflections. When the cut is too deep, the diamond may have poor sparkle, causing it to appear deceptively smaller. That underscores the importance of choosing a diamond of an ideal depth. With the right depth, a diamond should allow maximum light to pass through it, striking each pavilion facet at an angle that ensures most of the light 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, ranging from Poor to Excellent.

Since the depth is such a crucial aspect that determines the aesthetic appeal and the light performance of a diamond, it’s usually captured on a diamond grading report. In the report, you’ll spot two different measurements that are all described as diamond depth.

The first measurement denotes the total height of that diamond, expressed in millimeters. The second measurement is the depth percentage of the diamond.

Ideal Diamond Depth Percentages

To calculate the depth percentage of a diamond, you would need to divide the total height by the average diameter of the stone. Then, multiply the answer by 100. So, if a diamond’s average diameter is 10 millimeters and the stone has a total height of 6 millimeters, you would 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, there are certain recommended depth ranges that might guide you as you shop for a suitable gem. The following are the ideal diamond depth ranges for the popular diamond shapes out there;

Asscher 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 we’ve already highlighted, the depth of a diamond is crucial in helping customers to hone in on the best diamonds for them. But how do you leverage this critical aspect of a diamond structure while shopping for your dream gemstone?

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

Out of the Four Cs, you’ll discover that the cut is the most difficult aspect to determine. To be sure you’re getting the right diamond cut, you’ll ask for a diamond grading report from the seller. Now, on that report, check for the depth percentage that has been assigned to the round diamond that you’re purchasing. If it’s anything between 59 and 62.6%, then you’re sure the diamond has been perfectly cut and faceted. On the other hand, a depth percentage score outside the recommended range means the diamond hasn’t been well-faceted, and that may affect the stone’s sparkle and brilliance.

Diamond Table

What is a Diamond Table?

A diamond table is the flat, topmost, square-shaped facet of the diamond. The diamond table is so named due to the crucial position that it occupies and the role it plays in the diamond structure.

The fundamental function of a diamond table is refracting the rays of light that pass through the diamond and directing those rays to different facets of the stone. Like the depth, a diamond table also defines the fire, brilliance, and scintillation of a diamond, depending on how it handles the light that enters through the stone.

The size of a diamond’s table is one of the crucial factors that affect the appearance of the diamond. And there is a common misconception that the bigger a diamond table is, the more efficient it is at handling light. However, bigger diamond tables don’t necessarily translate to better light-handling properties. If a diamond table is too large, the upper facets of the stone may not have sufficient room to disperse light. Similarly, if the table is too small, minimal light will penetrate through the diamond, thereby diminishing its brilliance.


What’s The Ideal Diamond Table Size?

Naturally, you would expect larger diamonds to have proportionately larger table sizes, hence higher table percentages. But depending on how the diamond is cut and faceted, the size of the table may not always be relative to that of the entire stone. In most cases, consumers have to make a trade-off between fire and brilliance when trying to hone in on 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, as opposed to the table size. 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 Gem Society, the ideal table percentage of a diamond should range between 52 and 62%. But as you shall find, those percentages come down to individual preferences. Most importantly, an ideal diamond table percentage depends on the overall size and shape of the stone.

A diamond table percentage is arrived at by dividing the overall width of the table by the total width of the diamond, then 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’ll 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;

Asscher 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 don’t appear to vary significantly. However, those seemingly small variances have exponential effects on the overall brightness and appearance of a diamond. Like depth, understanding the ideal table percentage that particular diamond cut should have is invaluable when shopping for the gemstone.

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

It’s important to remember that out of the Four Cs, the diamond cut is the most difficult aspect to analyze. What appears like a round shape to the naked eye may turn out to be an oval shape. And even if you’re astute enough to distinguish between different diamond shapes and cuts, you may not be able to analyze the technical details relating to the 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’re buying comes with a grading report. And most importantly, the grading report must be from a reputable diamond grading lab. Diamonds that are certified by renowned grading labs, such as the Gemological Institute of America and the American Gem Society, often come with a report that indicates the stone’s depth and table percentages. Go through the report and before you check the depth and table measurements of the diamond, understand its cut grade. Since the depth and table percentages are finer aspects of a diamond’s cut, you want to ensure the stone is of your desired cut grade first.

For instance, you could be trying to make a choice between a diamond cut grade of Super Ideal Make and Ideal Make. Compared side by side, the diamond graded Super Ideal Make is definitely superior. However, if you’re making a comparison between two diamonds, each with a cut grade of Super Ideal Make, you may now compare their depth and table percentages. In which case, 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 don’t affect your budget significantly. As the values are expressed in percentages, they remain constant regardless of the weight, color, or clarity of your diamond. So, a diamond weighing 0.5 carats can have a depth or table percentage that’s 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?

One of the reasons to exercise diligence when choosing a diamond depth and table is that 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 lusture of a diamond. In simple terms, they influence how sparkling your diamond is. And we all know that looks is the main consideration when shopping for any jewelry.

Another reason to choose a diamond depth and table correctly is that they  determine the price of a diamond. It’s important to remember that jewelers usually leverage these seemingly trivial details while pricing their diamonds. You’ll often find that two stones that are similar in other aspects fetch different prices depending on their depth and table ratings.

Both the diamond depth and table measurements are designed to help shoppers to hunker down on their ideal stones. However, even if a diamond has values that fall within ideal ranges, you must consider other quality parameters as well. Above all, remember that the most important factor is your personal tastes and preferences. If a diamond appears excellent in your eyes, then nothing else matters.