Summary in a few lines:
A lot of people look for “heavier” diamonds (i.e. higher carat) because they want their diamonds to be special, visible, and sparkling.
Truth is, diamond sparkle isn’t only factored by diamond carat (and size), since other factors play a big role on this (mainly & most importantly the cut).
You can find some stunning diamonds with kind of lower carat (0.8) like this one, while if you search only for a larger diamond (still having some other good factors), you might end up getting a diamond like this 1.5 carat, but simply doesn’t worth a dime (both diamonds share same clarity, polish, symmetry, girdle, but the 1.5 has v. good cut vs excellent for the 0.8).
It’s worth mentioning that size differs for the same carat depending on diamond shape.
Let’s start with the basics…
What is Diamond Carat?
Maybe the statement above “2 carat isn’t double the size of 1 carat diamond” got your attention, so let’s take a quick look on what is a diamond carat and how it affects size.
Diamond carat is a weight unit as stated before, and it’s equal to 200 milligram, or 0.2 of a gram, you might think that 0.2 of a gram is so small & tiny, but truth is, it’s not small, at all!
The images we just saw are for 1 carat diamonds on a very “typical” finger size, as you see, they are quite visible and looks just perfect for her hand.
Now when you go twice that “weight”, remember that you’re seeing the diamond from the top mainly, and a lot of weight is filling the other parts of the diamond (depth), looking at this image gives us a bit more clarity:
The most visible parts of a diamond are table & crown, and doubling its carat as you see will have the weight distributed over the different parts, think of it like a 10 pound ball at the gym, and compare it to a 20 pound, is the 20 double the size?
Carat vs. Size: They Aren’t The Same
They are used interchangeably, but in reality they are not.
When selecting a diamond, understanding the difference between carat and size is crucial. Carat refers to the weight of the diamond, where one carat equals 200 milligrams. It’s a key factor in determining a diamond’s value but doesn’t directly indicate its physical size.
In contrast, the size of a diamond involves its actual dimensions—length, width, and depth—measured in millimeters.
This determines the diamond’s visible area, which is influenced by its shape and cut.
A common misconception is that a higher carat weight necessarily means a visibly larger diamond. However, two diamonds of the same carat weight can appear to be different sizes based on their cut.
Here is a visual representation for 3 exact diamonds in terms of carat, but their sizes are different based on their cut & proportions:
Different shapes can also give the illusion of varying sizes. Elongated shapes like oval, pear, or marquise can appear larger than round or square cuts of the same carat weight. This is due to their larger surface area, which makes them occupy more space on the finger.
Here are 3 identical diamonds in carat, but in different shapes, although round is the smallest (in appearance), it’s the most popular shape as it’s the best in reflecting light, making it more unique:
Images taken from James Allen.
So as you see, understanding this effect of shape is vital for making an informed choice that balances both the aesthetic and value aspects of your diamond selection.
How Setting Style Affect Diamond’s Perceived Size?
Not only the carat, neither the shape, but also the ring itself has some effect on this.
Yes, the setting of a diamond significantly affects how large it appears.
This aspect of diamond selection is often overlooked, yet it plays a crucial role in enhancing the stone’s visual impact. Different settings can create the illusion of a larger diamond, adding to its allure and appeal.
One of the most effective settings for maximizing the perceived size of a diamond is the halo setting.
In this design, the central diamond is encircled by a ring of smaller diamonds. This not only adds sparkle and brilliance but also creates a visual expansion of the central stone.
Another setting that influences the apparent size is the prong setting like this one on Blue Nile:
In this setting, the diamond is held in place by metal claws, where the delicate, minimal prong setting can make the diamond more visible and pronounced.
On the other hand, like in a bezel setting, where the metal surrounds the stone makes the diamond less visible and visibly smaller, like this ring:
The fewer the prongs, the more of the diamond is visible, enhancing its perceived size.
1 Carat Actual Size on Hand Fingers for Different Shapes
You probably have many questions already about how 1 carat diamonds look like in real hands.
Well, luckily, many online stores have provided great visualization tools to reflect how different shapes & carat sizes appear on hand. So, no need to worry about that!
And for the diamond size, it is usually determined by its weight, which is called carat, or as some people mistakenly type it karat, which is actually the gold purity (the confusion came since some countries like UK use carat for gold karat).
And by the way, a 2 carat ring doesn’t necessary mean that it’s double the size of a 1 carat.
As you can see from the photos here (credit: James Allen preview feature); these are all 1 carat diamonds, you can see how they actually look on average hand in Round, Heart, Princess, and Oval shapes:
Diamond Carat is NOT Gold Karat! Not Even Close
While this is not a common misconception, we have seen the confusion from some of our readers on multiple occasions; which’s why we’re setting some facts straight..
Gold purity is measured by karat (or in the UK it’s Carat, and that’s probably the reason for the confusion), it reflects the concentration of gold in the item; since not all gold jewelry is 100% made of gold.
So for example, when they say this gold ring is 24 Karat, it means that 24 out of 24 parts of this ring is made of gold (which is 100%), while in 18 karat, it’s 18⁄24 which is 75% pure gold.
Carat in diamonds has nothing to do with “purity” of a diamond. It’s simply a measuring unit for the weight/size of a diamond.
1 vs. 2 Carat Round Diamond Actual Size on Hand
Here is a visual comparison between 1 & 2 carat round diamonds (being the most popular shape) actual sizes on hand:
Indeed it’s larger, but in terms of dimensions, the 1 carat diamond has Length of 6.38mm, and Width 6.35, while the 2 carat L is 8.21 and W of 8.27.
These measurements are critical to understand how length, width, and depth play a huge role defining how diamonds reflect light.
The good thing is, you don’t need to go high carat to get an excellent diamond, and this is what our post about!
But keep in mind, 2 carat diamond is just larger than 1 carat diamond, not necessarily better!
Wondering why that 1 carat is more expensive than the average price of 1 carat diamond?
That’s because it has perfect internal symmetry and proportions, this collection on James Allen is called True Hearts™ Cut.
What is Diamond Carat Chart?
Diamond Carat Chart is a system of measuring the weight of a diamond particle, how it looks, and how large or small it is!
The chart is one of the factors considered when choosing a diamond piece because it’s one of the main characteristics of diamonds (4Cs).
Now that we have established that diamonds come in different shapes & sizes (it’s very common to refer to shapes as cuts by the way), do you know that shape & carat are very correlative? Why?
Because every diamond shape will affect how the diamond looks (even with similar carat).
For instance, let’s take a 1 carat princess-shaped diamond. It’d absolutely look different (in size) from an oval-shaped diamond as we saw in the image above.
Another fun fact: Do you know that many shapes look larger “in size” than round shapes? Check the table below.
But regardless, round is on most demand, why is that?
Because diamond beauty is mainly affected by how much light does that diamond reflect, and in terms of shape, the round brilliant cut is known to be the best here, i.e. its ability to reflect light exceeds other shapes.
That’s why carat is the last C among the 4Cs in order of importance!
Diamond Measurements & Size Chart per Carat
Diamonds Actual Size on Hand for Common Carat
Now that you’re aware of the various factors to be considered when buying that diamond ring, you probably have a good idea of what you want to get your special lady! The final step is to find a ring that fits perfectly, and you’re ready to go!
Since round shape is known to be the most popular shape of all time, princess cut comes second place, we will be showing the actual sizes for these shapes on hands.
Note: All images are taken from James Allen.
1/2 (half) Carat Diamond Actual Size on Fingers
On an average hand, here is how a 0.5 carat diamond looks like:
1 Carat Diamond Actual Size on Fingers
People consider the 1-carat diamond to be the “benchmark” for diamond sizes.
Here is how it looks on hand:
1.5 Carat Diamond Actual Size on Fingers
1.5 carat is also a great choice for a lot of people, it stands out effortlessly! Here are two images for the actual size of 1.5 carat diamonds on hand:
2 Carat Diamond Actual Size on Fingers
Going a bit “large”? Be careful with higher carat, not all hands are equal in size, some diamonds might appear a bit large on “tiny” hands, so if you’re getting such a high carat, here is how it looks on “average” hand:
3 Carat Diamond Actual Size on Fingers
Going wild? Make sure they don’t look very large on her hands, here is how 3 carat diamonds look:
Better Cut or Higher Carat?
Look at this image, it shows how the different cuts for a round diamond also have different sizes; taking into consideration that these 3 diamonds all of the same carat:
You can easily spot the diamond with the largest crown (the shallow one), and we hope you’re not even thinking about getting it, right?
Despite the fact that it looks bigger than other cuts, it sure has a very poor light reflection! An Excellent cut is what actually gives the diamond this sparkle and undeniable beauty!
Diamond excellent cut is way more important that getting a higher carat, so if you ask us, what is better: 1 carat excellent cut or 2 carat good cut? Definitely go with the 1 carat, no doubt about that.
Feel free to read our Cut Chart Article that will show in detail how each cut grade reflects light.
Buying Tip: Our Recommendation Based on Diamond Size Chart
On your hunt to find the perfect gem, whether you prefer the local stores, or even better (and way easier) buying diamonds online from some reputable names like James Allen & Blue Nile.
Always allocate the majority of your budget to secure an excellent cut, then start giving attention to Clarity, Color, and Carat.
For clarity, it’s recommended to start your search from SI1 grade as it’s eye-clean almost always.
If you’re uncertain about which carat range to choose from, it’s good to know that most people go with something a little under 1 carat for budgetary reasons.
Our last advice would be: Don’t go for the obvious!
Meaning? The demand is too high for the “1 carat” and the “1.5 carats”. We’d recommend that you go a bit lower on the carat to get a better price. Here’s an example:
If you want a diamond with 1 carat, go for the diamonds that are between 0.9 & 0.95 carats, it’s almost impossible to distinguish between such carat because their diameter is almost identical to the naked eye!
The same goes for 1.5 carats as well, go a little below, and you’ll find a better price per carat. These carats (0.9 – 0.95 & 1.4 – 1.45) demand is much lower than the known grades (1 & 1.5 respectively), and vendors use that to their advantage!
Still not sure where to buy your diamond?
We always recommend shopping diamonds online and created a Full guide to shop diamonds like a Pro.
Among online retailers, here are our favorite stores
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