How Carat Weight Affects a Diamond’s Price | BNT Diamonds
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How does carat weight affect the price of diamonds?

02 Dec 21

When buying a diamond (for investment or jewellery), you must understand the 4 Cs and the role they play in determining the price and value of the diamond.

In this brief guide, we will talk you through one of the most commonly known of the 4 Cs of diamond quality: the carat. We will cover the following topics to give you an idea of a diamond’s carat to price ratio and help you make an informed decision when it comes to buying the stone:

What is a carat?

The carat of a diamond is determined by its weight. The bigger the diamond, the higher the carat weight. One carat (sometimes denoted as ‘ct’) equals 200 milligrams.

It’s important to note that carat and size are not the same thing. The size of a diamond relates to its dimensions, and the cut can impact this. In other words, two stones of the same carat can have different dimensions and thus be different sizes. Conversely, you can have stones with either the same diameter or the same depth, for example, and these diamonds will have different carat weights.


Diamond price per carat

As you may have guessed, prices go up as diamond carat weight increases. However, prices increase exponentially rather than incrementally. Certain carat values called ‘magic numbers’ indicate where the diamond prices jump: 0.90 cts, 1.00 cts, 1.50 cts, 2.00 cts, 3.00 cts, 4.00 cts, and 5.00 cts.

This means that diamonds ranging from 0.01 to 0.90 cts, for example, have around the same price per carat. But, once above 0.90 cts, a diamond’s price per carat increases as it enters a new range.

To put this into perspective, the value of a 2-carat diamond is more likely triple the price (and not double) of a 1-carat diamond with similar characteristics. However, carat size alone does not determine the price of a diamond — there are the other 3 Cs to consider, too.

Diamond carat size and rarity

The price per carat jumps dramatically for each magic number specified above because larger diamonds are much rarer than smaller ones. Their rarity and the high demand for them pushes prices up significantly.

To give you an idea of the rarity of larger diamonds, here’s a rough estimate of the scarcity of gem-quality diamonds by carat size:

  • 1-carat diamonds: 1 in 1 million
  • 2-carat diamonds: 1 in 5 million
  • 3-carat diamonds: 1 in 15 million

High-quality diamonds from BNT Diamonds

BNT Diamonds buys diamonds straight from the source to offer you the best quality diamonds at the best price. In addition, all our diamonds have passed through a renowned certification agency, such as GIA, HRD or IGI.

If you are interested in buying diamonds as a value investment, contact our expert team by email or call directly on +32 3 201 24 90.

Fabienne Rauw
About Fabienne Rauw
BNT Diamonds Antwerp

Fabienne, manager of the German market is able to guide every client with finding the right jewel. She takes care of most of the German orders, but also takes other task on her plate. Thanks to her six years of experience at BNT Diamonds she acquainted well with the product and the marketing around it. Her degree in PR ensures that BNT Diamonds is well presented across all media channels. For anyone looking into a new investment opportunity, Fabienne is the perfect guide in this process. No question will be left unanswered, and she will help you every step of the way.

With this article, BNT Diamonds strives to inform you thoroughly about investing in diamonds. No investment can be guaranteed to be without risk or fully according to your expectations. That is why we recommend to research the risks and aspects of investing in diamond properly to ensure that you make the right choice for your portfolio.