When shopping for diamonds, one of the most common questions is: “What’s the difference between a 1-carat diamond and a 1.20-carat diamond?” On the surface, the difference might seem small, but when you compare the two, the differences in size, price, and appearance can make an impact. So, let’s break down what you should know before making a decision!
Size: Is There a Big Difference?
When it comes to carat weight, 1-carat diamonds are typically around 6.3 – 6.5mm in diameter. A 1.20-carat diamond, however, will usually measure around 6.75mm in diameter. This means that the 1.20-carat diamond is a little bit bigger – a subtle difference that can be noticed when the two are viewed side by side.
While the difference might sound tiny, in jewelry, even a fraction of a millimeter can have a significant impact on how the diamond looks on your finger. This size difference becomes even more noticeable with different diamond shapes. For example, a round brilliant cut will be 6.5mm for a 1-carat stone and 6.9mm for a 1.20-carat stone, giving you a slightly larger stone without dramatically increasing the price.
Light Performance and Brilliance
Good news: the light performance and brilliance of both a 1-carat and a 1.20-carat diamond will be virtually identicalas long as they have similar quality grades for cut, clarity, color, and symmetry. So, if you're deciding based on sparkle, the size difference won't matter much in terms of how the diamond looks in terms of fire and brilliance. The key difference is purely the size!
Diamonds in Different Shapes
If you're considering shapes beyond round brilliant, the size difference between a 1-carat and 1.20-carat diamond becomes clearer in different cuts. The table below outlines the approximate measurements for both carat weights in various popular diamond shapes:
| Diamond Shape | 1-Carat (mm) | 1.20-Carat (mm) |
|---|---|---|
| Round Brilliant | 6.5 | 6.9 |
| Princess Cut | 5.5 x 5.5 | 5.7 x 5.7 |
| Emerald Cut | 7.0 x 5.0 | 7.2 x 5.2 |
| Asscher Cut | 6.0 x 6.0 | 6.2 x 6.2 |
| Cushion Cut | 6.0 x 6.0 | 6.2 x 6.2 |
| Radiant Cut | 6.2 x 5.0 | 6.4 x 5.2 |
| Oval Cut | 8.0 x 5.5 | 8.2 x 5.7 |
| Marquise Cut | 10.0 x 5.0 | 10.2 x 5.2 |
| Pear Cut | 8.0 x 5.0 | 8.2 x 5.2 |
| Heart Cut | 6.5 x 6.5 | 6.7 x 6.7 |
As you can see, different shapes show different increases in size. For instance, a round brilliant increases by 0.4mm, while a princess cut only increases by 0.2mm. It's all about proportions when it comes to various cuts, so the overall increase in size might look different depending on the shape you choose.
Price Difference: Is It Worth It?
When comparing 1-carat vs. 1.20-carat diamonds, expect to pay roughly 20% more for the 1.20-carat stone, given the size difference. However, the price per carat remains the same for both diamonds, so it’s more about getting a bigger stone for a slightly higher price. Some sellers might apply a premium based on the rarity of the diamond’s specific characteristics (such as color and clarity), but the size difference itself is typically the main factor that influences cost.
Which One Should You Choose?
For many buyers, a 1-carat diamond is the sweet spot, offering great value, beautiful sparkle, and a manageable price. However, if you want a slightly larger stone with that extra bit of presence without dramatically increasing your budget, the 1.20-carat diamond could be perfect for you.
Some buyers choose a 1.20-carat stone because they feel it’s a more significant upgrade from the 1-carat size, or they may have personal reasons for choosing this size. For instance, one client of ours loved their 1-carat diamond but opted for the 1.20-carat stone as a way to mark a new chapter in their life. Whether it's upgrading over time or simply wanting a bigger stone, the choice is ultimately up to you!
Natural vs. Lab-Grown Diamonds
Did you know both natural and lab-grown diamonds come in 1-carat and 1.20-carat options? If you’re leaning towards a more ethical and cost-effective option, lab-grown diamonds can offer the same size and quality at a 50-60% lower price than natural diamonds. While lab-grown diamonds are identical to natural diamonds in every way except their origin, they generally hold less resale value. However, they provide an excellent opportunity to get a larger diamond without breaking the bank.
Final Thoughts: It's All About Your Preferences
When it comes to choosing between a 1-carat or 1.20-carat diamond, there’s no right or wrong answer—just what works best for you. The difference in size is subtle but noticeable, and the choice often comes down to your budget, style preferences, and what feels best for your finger (or your jewelry collection). Whether you go for the classic 1-carat diamond or the slightly larger 1.20-carat stone, both will offer amazing brilliance and beauty.