What Are Inclusions In Diamonds?

The clarity of a diamond is an important feature to consider when selecting a diamond. One of the fundamental aspects of a diamond that contributes to its clarity is the presence of inclusions.

What Are Inclusions?

Inclusions are minute imperfections within a diamond that occur when the diamond is formed. Since diamonds are created through extreme levels of pressure and heat, nearly all diamonds have inclusions, but the good news is that most inclusions are invisible to the naked eye. In most cases, a diamond's inclusions are only visible when it is viewed under a jeweler's loupe, which magnifies a stone from 10x to 30x its size.

Types Of Inclusions

Becoming familiar with some common types of inclusions can help you understand diamond grading and help you make an informed decision. The most commonly found inclusions are pinpoints & clouds, feathers or cleavage, and cavities.

Pinpoints & Clouds

A pinpoint inclusion is a tiny mineral crystal within the diamond that is often smaller than a particle of dust. Most pinpoints are too small to see without being magnified, and they can occur in clusters. A diamond can have a cluster of pinpoints that are so small that they are only noticeable as a slight haze or fog; these hazy clusters are known as clouds.

Feathers or Cleavage

Feather inclusions, sometimes called cleavage, are small cracks inside the diamond that have a feathered appearance at certain angles. Some large feather inclusions can be seen without magnification, but they are only a cause for concern if they affect the structural integrity of the stone. In many cases, feather inclusions are perfectly harmless and cannot be seen by the naked eye.


Cavities are indentations on the surface of the diamond, and like a cavity in a tooth, they typically denote a "hole" in the diamond. Usually, cavities occur during the polishing stage and can result from removing a crystal inclusion. Some diamond cutters will leave the cavity in the diamond because removing it would affect the carat weight of the stone.

Do Inclusions Affect The Value Of A Diamond?

Yes. Since inclusions affect the clarity of a diamond, they can affect the diamond's grade and overall value. When a diamond is graded by certified third parties, such as GIA and AGSL, a guideline that considers the location, size, and type of inclusion will determine the diamond's clarity grade. In general, external or visible inclusions will have a greater impact on the grade and value of the diamond.

When selecting a diamond, it is important to remember that almost all diamonds have inclusions. While there are aspects to take into consideration before making a purchase, inclusions can enrich the uniqueness and distinction of a diamond.

If you are considering purchasing a diamond and have questions about inclusions, clarity, or diamond grading, contact us, and the experts at Marci Jewelry will be happy to help.