BLOGS

Types Of Diamond Inclusions And Its Impact On Your Lab Grown Diamonds

By GDC Team | 23 Jun 2025 |

Table of Contents

What are diamond inclusions?

Lab grown diamonds with inclusions are usually cheaper than diamonds without inclusions. That’s because inclusions are impurities or imperfections and hence devalue the diamonds.

However, there are different types of inclusions and each may or may not impact the diamond based on the type and severity.

In this blog, we discuss the different types of diamond inclusions, how they impact diamonds, and more.

Let’s get started!

What are diamond inclusions?

Inclusions in mined or lab grown diamonds are imperfections that can occur during the process of the formation of the diamonds or afterwards. For instance, too much content of a certain gas or chemical could lead to imperfections in lab diamonds.

Conversely, a diamond without any imperfections can get scratches or marks on it due to improper handling. These are inclusions. There are many different types of diamond inclusions, which we will discuss in detail later in this article.

Why must you care about diamond inclusions?

Inclusions can impact diamonds in many ways, for instance, lab grown diamond price, clarity grade, performance grade, among others. Here are some ways in which inclusions can change diamond value and visual appeal:

Diamond factors	How inclusions impact
Visual appeal	Inclusions affect a diamond’s clarity grade. Visible inclusions can create dark spots, cloudy areas, or lines that interfere with light reflection and refraction. This can reduce the diamond’s brilliance and fire. The fewer and smaller the inclusions, the more light can travel through the stone unobstructed, creating better sparkle for the diamond.
Structural impact	Large or poorly positioned inclusions can create weak points in the lab grown diamond’s crystal structure. Feather inclusions, which are internal cracks, may expand under stress. This can cause the diamond to break. The inclusion type and location are crucial considerations beyond just the appearance of lab diamonds as they might affect the diamond shape.
Diamond pricing	Inclusions have a considerable effect on diamond pricing. A flawless lab grown diamond can cost significantly more than one with visible inclusions, even if they’re otherwise identical. Many inclusions are only visible under magnification. Diamonds with minor inclusions can offer excellent value while appearing eye-clean to the naked eye.
Authentification	Diamond inclusions help gemologists identify and authenticate diamonds. Diamond experts can distinguish natural diamonds from lab grown diamonds through inclusions, and also track individual diamonds. Some inclusions also provide clues about the diamond’s formation conditions, making them scientifically interesting features rather than just flaws. For instance, experts can know whether a lab grown diamond is made via HPHT or CVD process by observing the diamond inclusions.

Types of diamond inclusions

1. Clouds

Clouds are diamond inclusions that can occur in mined and lab grown diamonds. They are clusters of small white inclusions that look like clouds. Clouds can have a negative impact on diamond clarity grade. However, some jewelry experts may be able to create beautiful pieces out of lab grown diamonds with clouds.

2. Feathers

Feathers in lab diamonds are internal cracks and they look like feathers. If feathers are deep inside the diamond, they may not cause the diamond to break. Some feathers are not visible to the naked eye because of their location.

3. Needles

Needles are long and thin inclusions. If needles are large, they could affect the diamond clarity. However, most needles are small and may not be visible to the naked eye.

4. Twinning wisps

Twinning wisps look like cobwebs. At times there may be one or a cluster of them. When there’s a cluster, it might affect the diamond clarity.

5. Pinpoints

These are small sugar granules like imperfections that appear inside diamonds. They are so small, only noticeable through a magnifying device. And most often, pinpoints do not affect mined or lab grown diamonds in many ways.

6. Knots

Unlike pinpoints that are inside the diamond, knots appear on or near the surface of the diamond. Since they are close to the surface, they can cause damage to the diamond.

7. Cavities

Cavities are holes in the surface of a diamond. They can cause the diamond to break or chip as they are on the surface. Cavities also have an impact on the diamond shape as they have to be avoided during the process of polishing and cutting diamonds.

8. Internal graining

At times, mined and lab grown diamonds might have straight or curved lines inside them. These inclusions can impact the diamond clarity depending on the length and size of internal grains.

9. Crystal

Some diamonds have inclusions in the form of crystals formed inside them. Crystals can be of various colors and minerals. However, crystals do not appear on the surface of the diamond and hence, do not impact the lab grown diamond aesthetics.

10. Grain center

This inclusion appears like hazy lines and can be caused due to irregular growth in crystals. Depending on their size and depth, grain centers can also look like creases in the diamond.

Wrapping up

Now that you know a bit more about mined and lab grown diamond inclusions, buying diamonds will become a little more interesting and easier for you. If you’re looking for lab grown diamonds, explore Grown Diamond Corporation, for all kinds of diamonds in different shapes, carat weight, budget preference, colors, and more.