What You Should Know About Diamond Carat Weight And Diameter

The process of purchasing a diamond to be fitted in a piece of jewelry can be quite complex. This factor is especially problematic to a person who is not exceptionally experienced in the diamond industry. Trusting the wrong brand or making the wrong decision when it comes to buying a diamond can lead to a waste of money – such as when a person buys a diamond for its weight, but fails to take other factors into accounts, such as its cut quality and other particular properties that do not only affect its price, but also have a considerable impact on how the diamond looks.

When buying a diamond, a lot of people tend to think the more a diamond weights, the more impressive it will be and the bigger it will look. While this is technically true, there are some other factors that also come to play when buying a diamond – many other factors that actually have a considerable effect on how the diamond will look at how impressive it will truly be for the wearer. In this post, we would like to discuss the relation between diamond carat weight and diameter in size, and provide a basic overview of what other factors, apart from carat weight, should also be considered important.

Diamond Weight And Diameter – What You Need To Know

People who are inexperienced in the diamond industry often tend to think that the carat weight of a diamond plays the most part in determining the size of the diamond. While this belief has some truth behind it, being that the carat weight provides an overview of how big a diamond is, it is important for a person to take into account that carat weight is not all that affects how big a diamond will look once fitted inside a jewelry setting. A large part of a diamond is buried into a jewelry setting when it is fitted in an engagement ring, wedding band, set of earrings or even a pendant. Thus, only the top part of the diamond is visible after being fitted.

Once fitted, two other particular factors tend to play a large part in determining how big the diamond will appear physically. These two factors include the diamond’s diameter and its cut quality. A good cut quality will offer a better diameter, which means the diamond’s top part that will be visible after being fitted into a jewelry setting will appear larger. A diamond with a poor cut quality often does not have as large of a diameter, which means it will appear smaller.

A good example would be to compare a 0.90-carat diamond with a good cut quality to a 1.00-carat diamond with a poor cut quality. The cut quality can make a big difference – the 0.90-carat diamond may have a 6.2-millimetre diameter, whereas the 1.00 carat diamond would only have a 6.1 millimetre diameter. The 0.90 carat diamond would obviously be much cheaper than the 1.00 carat diamond as the price of a diamond tend to jump considerably once the “three-digit” carat weight (being 1.00 carat) is reached.


Numerous factors have a part to play in ensuring a diamond looks perfect and offers a good amount of brilliance and sparkle to the wearer. Unfortunately, a lot of people tend to look at the carat weight of a diamond solely when choosing to buy a larger stone, overlooking the fact that the diameter of the diamond, as well as the cut quality, also need to be taken into consideration to ensure the diamond looks good in the jewelry setting it will be placed in.

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Kevin Lee is a former tech advisor who cut his teeth in Silicon Valley. He now spends his time sharing his passion for investing in diamonds and jewelry. You can reach Kevin for any comments by using the contact form on this site. Don't forget to sign up for his free "Investing 101 Guide" by clicking on the button at the top right of this website.