Diamond Comparison: How to Compare Diamonds by Size, Quality, Shape & Price
Choosing between two diamonds isn't simple. Two diamonds can have the same carat weight yet look different on the finger. One may appear larger, another may sparkle more, and a third may offer a shape you prefer. That's why a useful diamond comparison involves comparing diamond shape, measurements, cut quality, color, clarity, certification, and price.
In this guide, we'll compare these factors in practical terms, including how different diamond shapes affect appearance and value. By the end, you'll know what to look for when you're comparing diamonds and how to decide which differences are worth paying for.
What Should You Compare When Comparing Diamonds?
|
Factor |
What it tells you |
|
Shape |
The diamond's outline and overall style |
|
Carat weight |
How much the diamond weighs |
|
Measurements |
Its length, width, and depth |
|
Cut quality |
How its proportions and facets affect light performance |
|
Color |
How much body color the diamond shows |
|
Clarity |
The presence and visibility of inclusions and blemishes |
|
Polish & symmetry |
The quality of the diamond's finish and facet alignment |
|
Certification |
How an independent laboratory has graded the diamond |
|
Price |
What you're paying for the combination of these characteristics |
You don't need to compare every factor while choosing a diamond for your jewelry. The important part is to compare the same factors across both diamonds.
And one detail that deserves special attention is a diamond’s measurements. Carat weight tells you a diamond's weight, but its millimeter dimensions show how much of that stone you'll actually see from above. Two diamonds with the same carat weight can have different face-up sizes.
Diamond Shape Comparison

Shape is the first difference you'll notice when two diamonds are put side by side. The ten shapes below are among the most used diamond shapes for engagement rings and other jewelry. They don't compete on a simple “best to worst” scale; each creates a different balance of sparkle, size, style, and price.
|
Diamond shape |
Appearance |
Light pattern |
Main advantage |
What to watch |
|
Round |
Circular |
Bright, balanced sparkle |
Strong brilliance and classical |
Usually higher price |
|
Oval |
Elongated |
Brilliant sparkle |
Good finger coverage |
Bow-tie effect |
|
Cushion |
Square or rectangular with rounded corners |
Soft to strong sparkle, depending on faceting |
Romantic look |
Faceting can vary widely |
|
Emerald |
Rectangular with clipped corners |
Broad, mirror-like flashes |
Elegant and vintage-looking |
Inclusions can be easier to see |
|
Radiant |
Square or rectangular with clipped corners |
Strong brilliance |
Combines a broad outline with sparkle |
Proportions vary considerably |
|
Princess |
Square |
Brilliant sparkle |
Geometrical appearance |
Corners need protection |
|
Pear |
Teardrop |
Brilliant sparkle |
Pointed and curved ends |
Bow-tie and pointed tip |
|
Marquise |
Long with pointed ends |
Brilliant sparkle |
Excellent finger coverage |
Bow-tie and pointed ends |
|
Asscher |
Square with clipped corners |
Broad step-cut flashes |
Strong geometric, vintage character |
Clarity can be more noticeable |
|
Heart |
Heart-shaped |
Brilliant sparkle |
Strong symbolic appeal |
Symmetry is especially important |
There's no universal winner here. Every diamond shape comes with its own benefits. If sparkle is your priority, you may go with a brilliant-cut shape. If visible size matters more, an elongated shape may be more appealing. And if you prefer an architectural look, an emerald or Asscher cut may suit you better.
For a detailed look at each shape, including its appearance, faceting, proportions, and styling possibilities, see our complete guide to diamond shapes.
Diamond Shape vs. Diamond Cut
People often get confused between diamond shape and diamond cut. As we saw earlier, diamond shape describes how a diamond appears to the eye, its silhouette and outline. Round, oval, pear, emerald, and marquise are all examples of diamond shapes.
Diamond cut is different. It describes how well the stone has been faceted and proportioned. When you look closely at a diamond, you'll see many small facets the flat surfaces cut into the stone. These facets are carefully arranged to interact with light, creating the brightness and sparkle you see when the diamond moves.
So, in simple terms:
-
Shape tells you what the diamond looks like.
-
Cut helps determine how the diamond performs.
There are two main faceting styles you'll encounter when comparing diamond cuts:
Brilliant Cut

Brilliant cuts use triangular and kite-shaped facets arranged to maximize light return. When the diamond moves, you see lots of bright flashes and sparkle. The round brilliant is the classic example, but brilliant-style faceting is also used in many fancy shapes, including oval, pear, marquise, and radiant diamonds.
Step Cut

Step cuts use long, rectangular facets arranged in parallel rows that resemble steps. Instead of the rapid sparkle of a brilliant cut, they produce broader flashes of light and a clean, mirror-like appearance. Emerald and Asscher diamonds are the best-known examples.
If you want a lively diamond with lots of sparkle, you should prefer a brilliant cut. If you like the softer sparkle and vintage look of a step cut, an emerald or Asscher may be more your style.
Diamond Sparkle Comparison
A diamond does sparkle in more than one way. Move it under a light, and you will notice bright white flashes, tiny bursts of color, or flashes that appear and disappear as the stone moves. These effects are categorised into three terms: brilliance, fire, and scintillation.
-
Brilliance: Brilliance is the white light you see coming back from the diamond. The way a diamond is faceted and proportioned affects how much light it returns and how bright it appears.
-
Fire: Fire is the colored flashes of light you see when white light separates into its spectral colors. These flashes can be especially noticeable as you move the diamond.
-
Scintillation: Scintillation is the pattern of light and dark flashes you see as either the diamond or the viewer moves. It's part of what gives a diamond its lively, changing appearance.
Diamond Color Comparison
When you compare two diamonds, color may not be as obvious as you expect. A diamond with a lower color grade doesn't always look noticeably warmer, especially when its shape and setting help disguise that color.
GIA grades diamonds in the D-to-Z color scale. As you move down the scale from D toward Z, the diamond shows increasing amounts of yellow or brown body color.
Once a diamond displays color beyond the range covered by the D-to-Z scale, it can fall into the fancy-color diamond category. Fancy-color diamonds occur in colors such as red, blue, pink, green, and black, with some colors being exceptionally rare and valuable.
But when you're comparing traditional white diamonds, there's another relationship worth knowing: diamond shape can affect how easily you see color.
How Diamond Shape Affects Color
Different shapes reveal body color differently because of their facet structure and the way light travels through the stone.
-
Round brilliant diamonds tend to hide body color well. This means you may be able to choose a slightly lower color grade without the diamond looking noticeably tinted.
-
Step-cut diamonds, such as emerald and Asscher, have larger, more open facets. These can make body color easier to notice.
-
Elongated brilliant shapes, including oval, pear, and marquise, can also show some warmth, although the effect varies from one diamond to another.
How Metal Color Affects Diamond Color
The metal surrounding your diamond can change how its color appears, too.
-
With white gold or platinum, a warmer diamond can contrast more strongly against the white metal, making its yellow tint easier to notice.
-
With yellow gold, that warmth can blend more naturally with the setting. So you may be comfortable choosing a slightly lower color grade, such as H or I, if the individual diamond still looks good to your eye.
When comparing diamonds, look at the color grade together with the shape and the metal you plan to use. That's a much more useful comparison than choosing the highest color grade automatically.
Diamond Clarity Comparison

When you look inside a diamond, you may find tiny natural features formed while the stone was developing deep within the Earth. These internal features are called inclusions, while surface characteristics are called blemishes.
Together, they determine a diamond's clarity grade.
Why does that matter when you're comparing diamonds? Because larger, more numerous, or strategically placed inclusions can become visible and, in some cases, interfere with the diamond's appearance and light performance.
GIA grades diamond clarity from Flawless (FL) to Included (I3). A Flawless diamond has no visible inclusions or blemishes under 10× magnification, while Included diamonds contain inclusions that are obvious at 10× and may also be visible to the naked eye.
|
Clarity range |
What you'll generally find |
What you may notice |
|
FL–IF |
No inclusions or blemishes visible to a skilled grader at 10×, or only minor blemishes in IF |
Extremely clean under magnification; the difference from lower grades is usually not visible to the naked eye |
|
VVS1–VVS2 |
Very small inclusions that are difficult to see at 10× |
Typically appears completely clean to the naked eye |
|
VS1–VS2 |
Minor inclusions that range from difficult to somewhat easy for a grader to see at 10× |
Often eye-clean, although the individual diamond matters |
|
SI1–SI2 |
More noticeable inclusions at 10× |
Some diamonds remain eye-clean, while others have visible inclusions |
|
I1–I3 |
Obvious inclusions at 10× |
Inclusions can be visible without magnification and may affect appearance; in some diamonds, durability can also be affected |
Which Clarity Is Better for Jewelry?
Higher clarity means fewer or less noticeable inclusions, but that doesn't mean you always need a Flawless diamond.
For an engagement ring or other everyday jewelry, eye-clean appearance is more useful than chasing the highest clarity grade. If a VS2 and a VVS2 look equally clean without magnification, the difference between their grades may be difficult to appreciate once the diamond is set.
Shape also matters. Step-cut diamonds have large, open facets that can make inclusions easier to notice. Brilliant-cut shapes tend to break up the view through their many facets, which can help hide smaller inclusions.
Diamond Price Comparison
Price is where all the previous comparisons come together. Two diamonds can have similar carat weights and clarity grades but still carry very different price tags. That's because diamond pricing isn't based on one characteristic. Carat weight, color, clarity, cut, shape, certification, origin, and market conditions can all influence what a diamond costs.
Why Can Two Similar Diamonds Have Different Prices?
Imagine you're comparing a 1-carat round diamond with a 1-carat oval diamond. Even if their color and clarity grades are similar, they don't necessarily have the same price.
Round diamonds often command higher prices because of their strong market demand and the amount of rough diamond that can be lost during the cutting process. Fancy shapes can sometimes offer a larger-looking diamond for the same budget, although their prices also vary considerably by shape and quality.
Certification matters as well. A diamond graded by a respected independent laboratory can carry a different price from a diamond with similar stated grades from another source. And then there's origin.
Natural and lab-grown diamonds can look very similar, but they are priced differently because they have different origins and market dynamics.
Natural vs. Lab-Grown Diamond Comparison
Another comparison you'll face when shopping for a diamond is natural vs. lab-grown. Both are diamonds with the same fundamental crystal structure and chemical composition. The difference is their origin: natural diamonds form through geological processes inside the Earth, while lab-grown diamonds are produced in controlled laboratory environments.
|
Factor |
Natural Diamond |
Lab-Grown Diamond |
|
Origin |
Formed naturally inside the Earth |
Grown in a laboratory |
|
Material |
Diamond |
Diamond |
|
Appearance |
Diamond appearance |
Diamond appearance |
|
Price |
Generally higher |
Generally lower |
|
Main difference |
Natural geological origin |
Laboratory origin |
How to Compare Two Diamonds Side by Side
Once you've narrowed your choices down to two diamonds, put the diamonds side by side and compare the things you'll actually notice when you wear them.
Start with the shape
First, decide whether you prefer the outline of one diamond over the other. If the shapes are different, remember that you're also comparing their visual coverage and faceting style.
Check the measurements
Look at the length × width × depth of both diamonds. This tells you more about their physical dimensions than carat weight alone. If one looks noticeably larger from the top, the measurements can help explain why.
Look at the diamond's light performance
Watch both diamonds under movement rather than judging them from a single still image.
Look for:
-
Bright white reflections
-
Colored flashes
-
Balanced light and dark areas
-
Any dull or overly dark zones
A diamond should look lively as it moves.
Compare color and clarity
Now look at the actual appearance rather than simply comparing the letters on the reports. If the difference isn't visible without magnification, you may not gain much by paying for the higher grade.
Check the grading report
Make sure you're comparing equivalent information from both reports, including:
-
Carat weight
-
Color
-
Clarity
-
Measurements
-
Cut grade, where applicable
-
Polish
-
Symmetry
-
Fluorescence
-
Laboratory
This helps prevent a seemingly cheaper diamond from looking like the better deal simply because you're comparing incomplete information.
Compare the price last
Once you've assessed the diamonds themselves, look at the price difference. Then ask the most useful question:
-
Can I see a meaningful difference that justifies paying more?
If yes, the premium price may be worthwhile. If both diamonds look equally good to you, the less expensive one may be the smarter choice.
Example: Comparing Two 1-Carat Diamonds
|
Comparison factor |
Diamond A |
Diamond B |
What to consider |
|
Shape |
Round brilliant |
Round brilliant |
Same shape, so the comparison is more direct |
|
Carat weight |
1.00 ct |
1.00 ct |
Same weight |
|
Measurements |
6.35 × 6.38 × 3.93 mm |
6.45 × 6.48 × 3.88 mm |
B has slightly larger face-up dimensions |
|
Color |
G |
H |
Both may appear white in the right setting |
|
Clarity |
VS1 |
VS2 |
Both may be eye-clean |
|
Cut |
Excellent |
Excellent |
Same overall grade, but proportions can still differ |
|
Polish |
Excellent |
Excellent |
Both have a high-quality finish |
|
Symmetry |
Excellent |
Very Good |
A has the higher symmetry grade |
|
Certification |
GIA |
GIA |
Comparable laboratory grading |
|
Price |
Higher |
Lower |
B may offer stronger value if the visual difference is minimal |
|
Best reason to choose |
Higher grades in some areas |
Slightly larger appearance and lower price |
Depends on what matters most to you |
Diamond Comparison by Buyer Priority
Once you've compared the technical details, ask yourself: what do you want most from your diamond? Your answer can change which characteristics deserve the biggest share of your budget.
|
If your priority is… |
What to compare first |
Diamonds to consider |
|
Maximum sparkle |
Light performance and proportions |
Round brilliant, oval, radiant |
|
Larger face-up appearance |
Length, width, and proportions |
Oval, marquise, pear |
|
Broad flashes of light |
Faceting pattern |
Emerald, Asscher |
|
Classic appearance |
Shape and brilliance |
Round |
|
Romantic look |
Shape and outline |
Cushion, pear, heart |
|
Modern geometric style |
Outline and facet pattern |
Princess, radiant, Asscher |
|
Lower price per carat |
Shape, quality, and total price |
Compare fancy shapes with rounds |
|
Eye-clean appearance |
Actual inclusions rather than grade alone |
Often VS or SI, depending on the stone |
Use your priority to narrow the choices, then compare the individual diamonds within that category.
When comparing diamonds for jewelry, understanding the grades and measurements isn't enough. You also need to consider how a particular diamond shape will work with the setting you plan to wear.
A round diamond is especially versatile and works well with almost any setting. Oval, pear, and marquise diamonds have elongated silhouettes that can create a lengthening effect on the finger, making them a natural choice for a more elongated or modern look.
Pointed shapes need extra attention. The tips of pear and marquise diamonds are more exposed to accidental impact, so they should be held securely with protective options such as V-prongs or a bezel setting.
Emerald and Asscher diamonds, with their clean step-cut faceting, also work beautifully in vintage-inspired engagement rings, particularly designs influenced by Art Deco jewelry.
If you want to explore how different settings work, including prong, bezel, halo, solitaire, three-stone, cathedral, and east-west settings, see our complete guide to engagement ring settings.
Note From Diagaa
Whatever diamond you choose, comparing your options helps you find the one that fits your style, needs, and budget. There’s no single perfect diamond for everyone. You may care most about sparkle, size, color, clarity, shape, or price.
At Diagaa, you’ll find both natural and lab-grown diamonds in different shapes and styles. Whether you’re looking for an engagement ring, wedding band, or another piece of diamond jewelry, we have options to suit your choice.
So take your time, compare the diamonds, choose the one you love, and find your perfect piece of jewelry at Diagaa.
