- The elements and characteristics of diamond cut
- What is a diamond girdle?
- What is a diamond culet?
- Estimating diamond carat weight by cut measurements
- Classification of diamond cuts
- Which is the most popular diamond cut?
- The round diamond cut
- Single cuts and full cuts
- Diamond accents
- Diamond chips
- Old European cut
- What are fancy cuts?
- Round cut vs. princess cut: differences
- Square cuts
- Triangular cuts
- Buying a trilliant cut (trillion cut)
- Princess cut vs. other square cuts: differences
- Radiant cut vs. princess cut
- Emerald cut vs. other rectangular cuts
- Emerald cut vs. radiant cut: Which to choose
- What is an Asscher cut?
- Asscher cut vs. princess cut
- What is a cushion cut?
- Cushion cut vs. Asscher cut
- Cushion cut vs. radiant cut
- Grading diamond cut quality
- Diamond symmetry and cut quality
- The ideal diamond cut: meaning
- How to tell if a cut is ideal
- “Excellent” vs. “Very Good” and “Good” cut
- Fine cut vs. ideal cut
- Deep and shallow diamond cuts
- Spread diamonds: What they are and how to buy them
- Princess cut: quality grading factors
- Radiant cut: evaluating quality
- Diamond chips and cut quality
- Uncut diamonds: quality evaluation and grading
- What diamond cut should I choose?
- How to compare diamond cuts
- How to find and identify an ideal diamond cut
- How to choose a princess cut
- How to buy an emerald cut
- How to choose a marquise cut
- What is the best diamond cut for earrings?
- Baguette cut: What it is and how to choose one
- How to find an affordable heart-shaped cut
- How should I choose a setting for my diamond’s cut?
- What is the best setting for a round cut?
- What is the best setting for an oval cut?
- What is the best setting for a rectangular cut?
- What is the best setting for a pear cut?
Diamond Cut Basics
What is diamond cut and why is it important?
Diamond cut refers to the proportions of a faceted diamond, the shape and positioning of its facets, and the general form of the stone. Cut is different from shape, which is a narrower characteristic referring only to the profile of the stone as viewed from above.
The way a diamond is cut determines how its facets will reflect light back to the eye of the observer – this is also called “light performance”. Light performance is extremely important for maximizing a diamond’s fire and brilliance.
How are diamonds cut?
Rough diamonds are cut using special saws and laser. The goal of the cutter when shaping a rough piece of material is to create one or more faceted stones that will sell for the maximum total price. This means that some diamonds will be cut will less-than-perfect proportions if doing so will help minimize waste and maximize profits.
Read more: How Diamonds Are Cut and Polished
How does cut affect diamond size?
The way a diamond is cut can affect its dimensions and perceived size. Diamonds that are cut shallow (i.e., they are wider but their vertical distance is shorter than normal) have a greater surface and look bigger compared with stones of similar weight that are cut deeper.
This relationship between cut proportions and size is why diamonds of different cuts vary in terms of how big they look when put in a setting.
Diamond Cut Elements, Characteristics, and Measurements
What are the elements and characteristics of diamond cut?
Diamonds are cut into faceted stones, and a cut is usually characterized by the measurements of some of its key elements: table (the stone’s topmost facet), girdle (its widest part), crown (the diamond’s upper part, above the girdle), and pavilion (the stone’s lower part, below the girdle).
The proportions of these parts and their alignment relative to one another are what characterizes a cut and determines its quality grade.
What is a diamond girdle?
The diamond girdle is the widest part of a cut diamond; it is the edge that separates the top (the table) and the bottom (the pavilion) parts of a stone. The girdle is the part that is measured when determining the diamond’s diameter (for round diamonds); the key proportions of other parts of a diamond are also measured relative to the girdle.
What is a diamond culet?
The diamond culet is the facet cut at the bottom of a diamond. Not all diamonds have a culet – some just have a pointed end at the bottom.
Some jewelers argue that the lack of a culet exposes a diamond to a greater risk of chipping at the bottom. Others think that this is not a problem as long as the diamond’s bottom is well protected when mounted in a setting.
If the culet is too big, it can be too visible through the stone’s top and look like a dark spot.
Can cut characteristics help me estimate a diamond’s carat weight?
Measuring some of the elements of a diamond’s cut can help you guess how much a diamond weighs. To estimate a stone’s carat weight, you need to use a formula, which usually uses the diameter of the girdle and the depth of the diamond as inputs.
These estimation formulas differ depending on the cut of the stone. Here are calculation guidelines for some of the more popular non-round diamond cuts: oval cut, princess cut, other rectangular cuts, heart-shaped cut, marquise cut and pear cut.
Types of Diamond Cuts
How are types of diamond cuts classified?
The round brilliant cut is considered the classic diamond cut; all other (non-round) cuts are referred to as fancy cuts.
Diamond cuts can also be divided into brilliant cuts (e.g., the round cut, the princess cut) and step cuts (e.g., the emerald cut). Brilliant cuts are designed to maximize the brilliance of the stone, whereas step cuts are not made with this priority in mind and therefore have less sparkle.
Which is the most popular diamond cut?
The most popular diamond cut is the round cut, largely due to its design, which is meant to maximize brilliance, more so than any other cut. The princess cut is usually the second most popular.
How is the cut of round diamonds measured and evaluated?
The round diamond cut is largely evaluated on the proportions of its table, crown, and pavilion relative to the stone’s girdle. To that end, diamond graders measure and calculate the diameter of the girdle, the diameter of the diamond’s table, as well as the crown height, the pavilion depth, and the total depth of the stone. The angles of the crown and the pavilion are also considered.
Read more: How to Measure Round Diamonds
What is a single cut and what is a full cut?
When referring to round diamonds, a full cut is a cut that has 57 or 58 facets – i.e., the number currently accepted as the standard for the classic round cut. Single cuts are those cuts with less than 57 facets – usually, between 16 and 18. Very small diamonds used as side stones often come in single cuts, as reducing the number of facets saves labor and makes the diamond cheaper.
What are diamond accents?
Diamond accents, or accent diamonds, are stones that are much smaller than diamonds used as center stones. Diamond accents are usually less than 0.25 carats, and most are 0.10 carats or less. They are cheap not only because of their small size, but also because of their simple cut, which has fewer facets than usual (a single cut).
What are diamond chips?
Diamond chips are small pieces of diamond that are not faceted or polished. Today, the term “diamond chips” is often used to refer to small diamonds (diamond accents) that have simplified cuts (single cuts).
What is an “old European cut”?
The old European cut is a round diamond cut that used to be popular until the early 20th century, when the modern round cut was created. Although the old European cut has the same number of facets as the contemporary round cut (58), the old European cut has different proportions – a smaller table, a higher crown, and a deeper pavilion.
What are fancy diamond cuts?
All diamond cuts different from the classic round cut are referred to as fancy cuts. One of the most popular fancy cuts is the princess cut.
How are the round cut and the princess cut different?
Apart from having a rectangular shape, the princess cut differs from the round cut in terms of brilliance – the princess cut has slightly less of it, all else being equal. As a result, yellow tints in princess-cut diamonds tend to be more easily visible than in round cuts.
Which diamond cuts have a square shape?
The following cuts have a square or rectangular shape: princess cut, cushion cut, emerald cut, Asscher cut, radiant cut, and baguette cut.
Read more: Types of Square-Looking Diamond Cuts
Which diamond cuts have a triangular shape?
The trilliant cut (or trillion cut) is a triangular diamond cut.
Should I buy a trilliant cut (trillion cut)?
Trilliants are a good choice if you are looking for a triangular stone, and since this cut is shallow, trilliant diamonds look relatively large for their carat when set. However, this advantage comes at the cost of reduced brilliance due to the lower depth of this cut. Trilliant diamonds are more often used as side stones than as center diamonds.
Read more: The Pros and Cons of Trillion-Cut Diamonds
How is the princess cut different from other square diamond cuts?
Compared to most other square-cut/rectangular-cut diamonds, the princess cut tends to have more brilliance. Other differences are in the general shape (e.g., many of the other square cuts have truncated corners, unlike the princess cut) and in the number of facets.
What is a radiant cut and how is it different from princess cut?
The radiant cut is a rectangular cut, but unlike the princess cut, its four corners are truncated. The two cuts also differ in the pattern of their sparkle. Another difference is that radiant cuts tend to show more color, whereas yellowish tints are less noticeable in princess cuts. However, all these differences are slight and not necessarily readily noticeable.
What is an emerald cut and how is it different from other rectangular cuts?
The emerald cut is a rectangular cut with truncated corners. The difference between it and the most other popular rectangular cuts is that the emerald cut is a step cut, not a brilliant cut. This means that the emerald cut’s facets are arranged in a different way and it is not designed to maximize brilliance.
Should I choose an emerald cut or a radiant cut?
Unlike the emerald cut, the radiant cut is classified as a mixed cut – i.e., it has features of both brilliant and step cuts. For that reason, the radiant cut exhibits more brilliance, so if that’s what you are looking for, a radiant diamond is a better choice. Don’t discount the emerald cut, though – it has its own beauty, and many people prefer it exactly because it is less sparkly.
What is an Asscher cut?
The Asscher cut is a rectangular step cut whose sides are approximately equal. It is the square variation of the emerald cut.
Should I buy an Asscher cut or a princess cut?
This decision is down to your personal preferences. If brilliance is a priority, then the princess cut is the winner. Its sparkle is also better able to mask flaws and color tints. If you prefer a stone with a milder shine, then the Asscher cut is a good choice.
What is a cushion cut?
The cushion cut is a type of brilliant cut with a rectangular outline and rounded corners. There are many variations of the cushion cut, and they vary in the number, shape, and positioning of their facets. This is why it is hard to pin down many characteristics that are constant beyond the cushion cut’s general shape.
Should I choose a cushion cut or an Asscher cut?
Most cushion cuts will have more sparkle than Asscher cuts, so if this is important to you, a cushion-cut diamond may be a better choice. Asscher cuts, on the other hand, have a softer brilliance, which you may like better. There are cushion cut variations that are less sparkly, so it’s always best to compare Asscher-cut and cushion-cut stones visually before deciding.
Should I buy a cushion cut or a radiant cut?
The most visible difference between the radiant cut and the cushion cut is in their shape – the former has a more angular outline, whereas the latter looks more rounded. These two cuts are pretty close in terms of brilliance and sparkle, as well as in how visible inclusions and yellow tints in them are. This is why it is best to decide between the two on a case-by-case basis.
Diamond Cut Quality and Cut Grading
How is the quality of a diamond’s cut graded?
Diamond cut is graded by measuring the proportions of the stone and assigning a cut quality level to it depending on how close these proportions are to a cut standard considered ideal.
Is symmetry an important factor for diamond cut quality?
Diamond symmetry refers to how regularly shaped and well aligned a stone’s facets are. Symmetry is often evaluated separately from diamond cut, although symmetry can be considered an attribute of cut. In GIA diamond reports, symmetry is given a separate grade (from Excellent down to Poor). Although symmetry and cut grades in most diamond certificates measure slightly different things, asymmetrical facets can spoil the appearance of a diamond in a similar way a bad cut does.
What does “ideal cut” mean?
The term “ideal cut” is used to refer mostly to round diamonds. An ideal cut is one whose proportions allow it to maximize brilliance and sparkle through bending and reflecting light in the most optimal way. Ideal cut proportions are used as a standard against which diamonds are evaluated for cut quality.
Read more: What Is an Ideal Diamond Cut?
How do I know that a diamond cut is ideal?
Diamond whose cut is as close as possible to the ideal standard will be assigned the highest cut grade (“Excellent” on the GIA scale). Some of the most important ideal proportions for the round cut are: 53%-57% for table diameter, 14.4%-16.2% for crown height, and 43.1%-43.2% for pavilion depth (all figures are expressed as a percentage of girdle diameter).
Should I buy a cut graded “Excellent”? Is a “Very Good” or “Good” cut good enough?
Buying the best cut grade will provide you with more brilliance compared to diamonds with the same clarity and color characteristics that are a notch lower on the cut scale. If that is important to you, then buying an “Excellent” cut (on the GIA scale) is worth it.
Keep in mind that buying the best cut possible will make an even bigger difference for stones of lower clarity and color – since brilliance can make inclusions and yellow tints less visible, maximizing this characteristic through buying the best-proportioned diamond possible can have a noticeable effect on how your stone looks.
What is a fine cut and how is it different from ideal cut?
“Fine cut” is a term used mostly in Europe to denote a cut with proportions that allow a diamond to achieve maximum brilliance. In this sense, the meaning of “fine cut” is the same as “ideal cut”, and the latter term is more widely used in the U.S. There are, however, some slight differences between the perfect proportions prescribed by the fine cut standard and those of the ideal cut.
Can a diamond cut be too deep or too shallow?
The depth of a diamond is measured as the vertical distance from its top facet to its bottom (total depth) or as the distance from the girdle to the bottom (pavilion depth). It is accepted that a pavilion depth of around 43% is ideal and that a total depth of 57.5% to 59.45% is the most desirable for round diamonds.
Stones that are too shallow or too deep relative to these standards will lack the brilliance diamonds with closer-to-perfect proportions have. In addition, when in a setting, deep-cut diamonds look smaller for their carat weight compared with shallower-cut stones, which have more visible surface area.
What is a “spread diamond”? Should I buy spread diamonds?
Spread diamonds are stones that have been cut much shallower than diamonds whose depth is close to ideal. As a result, spread diamonds are wider than better-cut stones of similar carat weight. This is what makes spread diamonds look bigger when put in a setting.
If you care about how big your diamond looks but your budget is limited, a spread diamond may be a viable choice. However, keep in mind that spread diamonds have reduced brilliance, as their sub-optimal depth causes most of the light entering them to leak out through the bottom instead of being reflected back to the eye of the observer.
How is the quality of princess cuts graded? What are the most important quality factors I should be evaluating?
Although there is not such a robust grading system for princess cuts as there is for round cuts, the way the quality of the princess cut is judged is essentially the same – by looking at its key elements (such as the girdle, the table, the crown, and the pavilion) and measuring them to calculate their proportions.
The most important quality factors for a princess cut are its total depth relative to the stone’s width, the width of the table relative to the width of the girdle, the stone’s length-to-width ratio, and the thickness of the diamond’s girdle.
How is the quality of radiant cuts evaluated?
The quality of radiant cuts is assessed by measuring their total depth, table width, girdle width, and girdle thickness. The most important quality factors derived from these measurements are the cut’s table ratio (table width to girdle width) and total depth ratio (total depth to girdle width).
Read more: How Are Radiant-Cut Diamonds Graded?
Is cut quality important for diamond chips?
Real diamond chips, i.e. pieces chipped of a bigger rough diamond, are not faceted or polished, so cut quality is irrelevant when evaluating them.
What people and jewelers often refer to as diamond chips today are the so-called single-cut diamonds, or melee diamonds. These stones are small, less than 0.20-0.15 carats, often 0.10 carats or less. They are actually faceted, but their cut is simplified – i.e., it has less than the usual number of facets.
Because faceted diamond chips are small and are usually used as accent stones, their proportions and brilliance are less of a concern than they are for bigger center stones. As a result, cut quality is not that important for chips.
Read more: What Is the Value of Diamond Chips?
How is the quality of uncut diamonds evaluated and graded?
Since uncut diamonds are not faceted, they cannot be graded on cut, and they are evaluated only on their color, clarity, and carat.
There is another factor that comes into play for rough diamonds – the shape of the uncut piece. This shape determines the potential size, cut quality, and clarity of the faceted diamonds that can be cut out of the piece. Generally, pieces that allow more proportional and cleaner diamonds to be cut from them are worth more.
Read more: How Are Uncut Diamonds Measured and Valued?
How to Select and Buy Diamond Cut
What diamond cut should I choose?
Cut quality is a major factor that determines how much brilliance your diamond will have. Brilliance is important not only because it looks nice but also because it can mask yellow tints and inclusions. This is why cut becomes even more important for diamonds of lower-quality color and clarity. And since imperfections are even more visible in bigger stones, the importance of cut also increases with carat.
In general, cut is the one quality characteristic that you should not skimp on, if your budget allows it. For round diamonds, we do not recommend going below cuts graded “Good” on the GIA scale, as poor cuts look dark and their flaws are more visible. If you can afford it, opt for a cut graded “Excellent”, even if this means slightly downgrading on color or clarity.
Read more: How to Select the Cut of a Diamond
How should I compare different diamond cuts?
If you are comparing round cuts for diamonds that are graded, you can look at their grades to find out which cut is better. If the stones are not certified, you can measure their key proportions such as table diameter, crown height, and pavilion depth, each divided by the diameter of the girdle. (See our Cut Grading section for more information on what benchmarks to use for these ratios.)
If you don’t have the measurements of the stones you are comparing, or if their cuts are different (e.g., you are comparing a round diamond with a princess-cut diamond), then it’s best to go by how they look. In such cases, your eyes should be the judge – if one diamond looks brighter and more brilliant, chances are its cut is a better choice.
Read more: How Should You Compare Diamond Cuts?
How can I find and identify an ideal diamond cut?
The fastest way to find and identify a round ideal-cut diamond is to look only at certified stones and check their cut grades in their diamond reports. The diamonds with ideal proportions will have the highest cut grade on the respective scale (“Excellent” on the GIA scale).
You can also look at the proportions of the stone. An ideal round cut will have a table whose diameter is between 53% and 57.5% of that of the girdle, a crown height that is 14.4%-16.2% of the same measure, and a pavilion depth that is around 43% of the girdle diameter.
Read more: How to Find an Ideal-Cut Diamond
How should I choose a princess cut?
The best princess cuts have a total depth (the vertical distance from the top facet to the bottom) that is about 70% (65%-75%) of their width (as measured at the girdle). As for color and clarity, go for the lowest grades in which yellow tints and flaws are not readily visible with the naked eye (for most princess cuts, the recommended ranges are H-I for color and VS1-SI1 for clarity).
Read more: Tips on Buying Princess Cut Diamonds
How should I buy an emerald cut?
It is best to buy emerald cuts whose total depth is about 60%-70% of their width. To get the best value, choose a color in the G-H range and clarity in the VS1-VS2 range.
Read more: How to Choose an Emerald-Cut Diamond
How should I go about choosing a good marquise cut?
The best marquise cuts have a table whose length is about 53%-63% of the length of the girdle, a crown height that is 12%-15% of the girdle, and a total depth that is around 60% of the girdle. The cut should be symmetrical – its ends should be aligned, and its left and right sides should look identical.
What is the best diamond cut to buy for diamond earrings?
The round cut is the best choice in terms of brilliance, while step cuts such as the emerald cut and the Asscher cut have the least sparkle.
The oval cut and its derivatives (such as the marquise cut and the pear cut) are more suitable if you want your earrings to give the impression of length. Square cuts look wider and are most suitable for broader faces.
What is baguette cut and how should I choose one?
The baguette cut has a rectangular shape and is classified as a step cut. Baguette-cut diamonds are usually used as side stones.
Because this type of cut is not designed to maximize brilliance, depth is not an important consideration for baguettes. This is why it is recommended that you go for shallower baguette cuts in order to maximize the visible surface of the stone when set.
Read more: How to Choose a Baguette Cut Diamond
How can I find an affordable heart-shaped cut?
To save money on heart-shaped cut, go for eye-clean SI1 or SI2 clarity and a color grade in the I-J range. As for cut proportions, table width should be 52% to 65% of the width of the stone, as measured at the girdle; total depth should be 53% to 70% of the width of the girdle.
Diamond Cut and Settings
How should I choose a setting for my diamond’s cut?
Make sure that the vulnerable parts of the cut – e.g., sharp ends and thin edges – will be well protected by the setting you choose. If the diamond has visible flaws, it is best if the setting can hide some or all of them.
Make sure that you understand the tradeoff between visibility and safety – settings that leave more of the diamond visible also expose it to a greater risk of potential blows, whereas safer settings reduce the visibility of the stone they protect.
Read more: Diamond Jewelry: Settings and Styles
What is the best setting for a round cut?
There is no single best setting for a round cut because different settings are best for different circumstances. If safety is a priority, the bezel setting is one of the most popular choices. If you want more visibility for your stone, then a prong setting would be a better choice.
What is the best setting for an oval cut?
4-prong and 6-prong settings are quite popular for oval cuts. If you are concerned that you might accidentally hit your diamond, then a bezel setting offers better protection against the risk of damage or the stone falling off. Partial bezel settings leave more of the stone visible than full bezel settings.
What is the best setting for a rectangular cut?
As with other cuts, prong settings are very popular for rectangular cuts because prongs hide less of the diamond. For rectangular cuts with sharp ends, such as the princess cut, it is best to opt for a V-prong setting, which will protect these vulnerable parts better than regular rounded prongs. Pick a bezel setting if you want even greater safety.
What is the best setting for a pear cut?
The most important consideration when picking a setting for a pear cut is to protect its pointed end. So, if you opt for a prong setting, make sure that the sharp end of the stone is held by a prong. As for the recommended number of prongs, more prongs provide additional safety – the stone is less likely to fall out of them and will be better protected in case the setting gets hit.
A full bezel setting is another good option, especially if you are going to wear your pear-cut stone when doing activities during which it may get hit – the bezel will offer additional protection.
Where to Buy Diamonds and Diamond Jewelry?
For diamond jewelry, we highly recommend James Allen because it shows real photos and videos for each diamond so you can take a 360-degree look at any stone before buying it.
For colored diamonds, we recommend Leibish & Co., which specializes in fancy color diamonds (use code JewelryNotes200 at checkout to get a 5% discount).