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Flawless vs. internally flawless diamonds

GIA certificate of a flawless diamond

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Flawless diamonds, with their perfect clarity and extreme rarity, are a true marvel of nature.

In this article, we explore the world of flawless vs. internally flawless diamonds and learn about their desirability, value and how they compare. 

Join us as we embark on a journey to uncover the secrets of flawless and internally flawless diamonds and discover the perfect gem that resonates with your unique style and preferences.

What is a flawless diamond?

A flawless diamond (FL) is a diamond that has no inclusions or blemishes visible to a skilled grader using 10x magnification. This is the highest grade in the Gemological Institute of America (GIA) scale for clarity.

Clarity is one of the Four Cs (Carat, Cut, Color, Clarity) that determine the quality and price of a diamond. The clarity of a diamond is evaluated based on the absence of inclusions and blemishes:

  • Inclusions are internal characteristics such as crystals or mineral traces trapped within the diamond during its formation. They can also impact a diamond's structural integrity. Diamonds are the hardest mineral, which means they won't get scratched (except by another diamond), but too many inclusions can make a diamond brittle. Fortunately, this is rare and only happens when diamonds are very heavily included.
  • Blemishes, on the other hand, are simply surface characteristics such as scratches, pits, or chips.

Flawless diamonds are extremely rare and valuable because the vast majority of diamonds have inclusions or blemishes that formed naturally as the diamond crystallised, whether deep within the Earth in the case of natural diamonds or during the creation of lab grown diamonds.

What is an internally flawless diamond?

An Internally Flawless (IF) diamond is one grade below Flawless (FL) on the Gemological Institute of America (GIA) clarity scale. This grade means that a diamond has no inclusions visible under 10x magnification to a skilled grader, but it has very minor blemishes (external characteristics) that are extremely difficult to see even under magnification.

Internally flawless diamonds are also incredibly rare and valuable, being just one step below flawless diamonds. The difference between FL and IF diamonds can often be incredibly subtle, even for a skilled grader to see under magnification.

Flawless vs internally flawless

Below you can view a video of a highly magnified flawless diamond. As you would expect, there are no visible inclusions or blemishes:

A flawless (FL clarity) diamond

Whereas the diamond below has been graded as Internally Flawless (IF), meaning that the diamond grader was able to see some very minor surface blemishes at 10x magnification. However, to the untrained eye, it is impossible to discern any difference in clarity between the FL diamond above and IF diamond below.

An internally flawless (IF clarity) diamond

How to choose your perfect diamond

While it is very important to consider clarity when choosing a diamond, it is important to remember that a diamond's overall allure is determined by other factors as well, in particular, its carat weight, colour and cut. For this reason, it is important to weigh up all of these and consider your own personal priorities. For example, is size more important than quality to you, or would you prefer a higher quality smaller diamond for the same money? To help you make the right choice for you, read our guide on selecting the perfect diamond.


What percentage of diamonds are flawless?

Flawless diamonds are extremely rare. According to the Gemological Institute of America (GIA), fewer than 1% of all diamonds examined in their labs are given a Flawless clarity grade. In fact, the number may be well below that, with some estimates suggesting that only around 0.001% to 0.01% of diamonds are truly flawless.

Are internally flawless diamonds worth it?

The value of an Internally Flawless (IF) diamond depends on your preferences and budget. These rare gems exhibit no visible inclusions under 10x magnification, exuding absolute perfection and rarity. While some argue that diamonds with slightly lower clarity grades can offer better value for money, the visibility of inclusions is often negligible to the naked eye. This means that unless you look at your diamond under magnification, you may not notice a difference in appearance. By opting for a lower clarity grade, you can save money and prioritise other essential factors like carat size, cut quality, and colour grade.
Whether you choose an IF diamond or a slightly lower clarity grade, finding the perfect diamond that suits your preferences can be an overwhelming task. As with all aspects of buying diamonds, the key is to choose what's most important to you within your budget. If you need further guidance to help you choose a beautiful diamond, contact us today, and someone from our team will be very happy to assist you.


Flawless diamonds (FL) exhibit perfect clarity with no visible inclusions or blemishes under 10x magnification. On the other hand, internally flawless (IF) diamonds also have no visible inclusions but do possess minor surface blemishes, though these remain difficult to see even under 10x magnification.

In terms of value, flawless diamonds are more valuable than internally flawless diamonds (all else being equal) due to their rarity and status as having the highest clarity possible. However, price variations depend on factors like size, colour, and cut quality. When purchasing a diamond, it's vital to consider your personal preferences, budget, and overall appearance of the diamond.

Remember, a diamond's allure extends beyond its clarity alone. A diamond that is internally flawless but lacks a superb cut or colour might not exhibit the same stunning beauty as a slightly included diamond with exceptional cut and colour grades. Make a well-informed decision that aligns with your preferences and budget when selecting your perfect diamond. Explore our extensive inventory of lab-grown diamonds or Canadian diamonds to discover the diamond that speaks to you, or get in touch with one of our experts if you need help with finding your perfect diamond.

Tim Ingle
Together with David Rhode, Tim created Ingle & Rhode to offer a better alternative to the traditional luxury brands. Since 2007, we’ve provided our customers with genuinely ethical engagement rings, wedding rings and fine jewellery – free from conflict diamonds, dirty gold and child labour. With more than 16 years experience in the jewellery industry, Tim has deep expertise in diamonds, gemstones and jewellery design and manufacturing.