The following is a list of the different types of inclusions in a diamond (photography credits – James Allen) that are commonly found.
Bearding – Hair-like inclusions that form at the girdle under stress due to improper bruting of the diamond.
Cavity – This usually takes the form of a large or deep opening in the diamond’s surface. Cavities are usually created on the surface of the diamond during polishing when an internal inclusion like a crystal drops out of its pocket. Read this article for more insights.
Crystals – Included minerals that exist within the body of the diamond. Depending on the type of minerals they are, they can be colorless (another diamond embedded with), black (carbon), reddish (garnets), greenish (peridots) and etc… Larger and colored crystals are much more obvious to the naked eye and are very much unwanted.
Crystals Can Exist In Different Types of Shapes And Colors
Cloud – This usually refers to a small cluster of pinpoints or crystals that are very close to each other. It can also be a broad term used to classify different types of inclusions together. When clouds get too big in size and density, they can cause the diamond to take up a hazy appearance and affects brilliance.
Visible White Cloud Sets The Grade In This SI1 Emerald Cut
Varying Intensities And Colored Clouds
Feather – A small crack or fracture within the diamond. They usually appear white and vary in sizes and shapes. Severe feathers can cause durability issues or have unsightly coloration to them.
Additional risks of chipping and coloration causes feathers to appear more obvious
Needle – A long thin needle-shaped inclusion that is usually white in color. This kind of inclusion is usually small and looks like a tiny rod. If they appear in clusters, it might affect cause a detrimental effect on the diamond’s clarity.
Super obvious needle that runs across the middle of the stone
Small Elongated Needle Under Table Facet
Pinpoints – These are very small white or black crystals that are embedded inside a diamond.
Can You See Faint White Pinpoint?
Twinning Wisps – Formed as a result of growth defects in a diamond’s crystal structure during the creation process. When conditions become unfavorable, the diamond stops growing and continues its growth (say for example thousands of years later) in a different direction. Twinning wisps are a mish-mash of different inclusions such as pinpoints, crystals, feathers, clouds and crystals that forms a somewhat twirly plane.
Faint Twinning Wisp That Can Hardly be Made Out
This video shows a heavily twinned heart cut with an I1 clarity.
Chip – A small opening on the surface of a diamond typically found near edges or facet junctions. This damage is typically caused by wear and tear or accidental knocks.
Indented Natural - A flaw which dips below the polished diamond’s surface. This is a part of the rough diamond that was left untouched in the polishing process. Indented naturals are usually found at the girdle.
Indented natural indicated by red arrows. Source: GIA
Did you know that many shoppers actually make a crucial mistake when selecting their diamonds that is based solely on information from a grading report? There are so much hidden details that the lab reports NEVER reveal to you. On the next page, we’ll show you how to overcome the pitfalls of buying blind…