The extent of inclusions present in a diamond is an important consideration in your decision. Although nearly every diamond has some degree of inclusions, not all are created equal.
Avoid inclusions such as chips and dark crystals that compromise the durability of a diamond or are noticeable without magnification. When one or both of these factors are present, it diminishes its appearance and quality. Instead, choose an eye-clean diamond to earn exceptional value over a flawless one.
Let’s explore seven diamond inclusions to avoid and the details on each.
What are Diamond Inclusions?
Inclusions are imperfections on a diamond that develop during its formation under the earth or throughout the cutting process. Inclusions are categorized by whether they’re on its surface or interior.
Examples of surface inclusions are fractures, chips, naturals, and scratches, and interior inclusions include etch channels, clouds, feathers, cavities, and twinning wisps.
They vary in size, position, and color, and the extent of a diamond’s inclusions influence its clarity grade, which ranges from flawless to I3, where each steps down from flawless indicates more impactful blemishes.
The presence of inclusions significantly impacts the quality of a diamond, so a flawless one with no inclusions visible at 10X magnification results in a premium price.
Which Diamond Inclusions Should You Avoid?
1. Chips
Chips are a type of diamond inclusion that feature a shallow, small opening on the surface. It usually forms near the girdle, culet, or where the facets intersect with each other. They’re most frequently caused by human error such as a drop or hit against a hard surface.
The reason you should avoid diamonds with chip inclusions is because it’s more likely to chip again in the future. The initial chip makes it more susceptible to future breaks, which erodes the value and appearance of the diamond.
Chips can be fixed, but it requires recutting the diamond.
This removes carat weight, resulting in a smaller and less valuable diamond.
Instead of choosing a diamond with a chip because the price is lower, you should instead buy a smaller diamond that isn’t chipped. It’s better to have a diamond with a lower carat weight that isn’t chipped versus a larger one with that inclusion.
2. Dark Crystals
Crystal inclusions form within a diamond. In some cases, it’s a small emerald or ruby, and even though it may sound like that should increase its value, it does the opposite.
You don’t always need to avoid diamonds with crystals. Some are clear and will have a minimal impact on its quality, but the ones you should steer clear from are dark crystals. They can form in many colors such as red, green, and blue, and they cause issues with light performance.
Crystals prevent light from entering the stone. It reduces the fire and glimmer in the diamond, making it appear dull.
If you choose a diamond with this inclusion, opt for one with transparent crystals or ones that are small and spread out across the diamond.
Even better, choose one where the crystals are covered by the setting, so they’re in an area that wouldn’t be receiving light anyway.
3. Feathers
Feathers refer to a crack, break, or fracture in a diamond. They earn their name because they often look like a feather has been lodged inside. Feathers can be black or white and vary in their size and location in a diamond.
Certain instances of feather inclusions should be avoided for two reasons.
First, long, large feathers located near the girdle can cause durability issues. Depending on the girdle’s thickness, it can be the weakest area of a diamond, so the addition of an inclusion only worsens this problem.
Secondly, large, dark feathers reduce a diamond’s brilliance. It prevents light from properly entering and exiting the diamond.
The extent of this problem is dependent on the size, color, and location of the feather. That means if there are small, transparent feathers in an excellent or very good cut diamond, it can still have strong light performance.
4. Cavities
Cavity inclusions are similar to chips. It’s a large crater or hole in its surface. Most cavities aren’t caused by the pressure a diamond experiences during its formation. Instead, it’s a man-made error.
When a diamond is polished, weaker parts of it can be dislodged.
The reason you should avoid diamonds with large cavities is because of durability and appearance. The hole leaves it vulnerable to more breaks, and they can also fill with dirt and grime. Over time, the debris can create black spots visible to the naked eye.
Like chips, cavities can be removed from a diamond.
But the problem is the same in that it reduces its carat weight and diminishes its value.
It’s often better to choose a smaller diamond without a cavity inclusion rather than risk its durability and appearance or choose to cut it down to a lower weight.
5. Laser Drill Holes
Laser drill holes are a diamond inclusion that result from removing another type of inclusion.
If there’s a flaw on the inside of the diamond the seller wants to remove, they can drill a small hole to open a path to the inclusion. The diamond is boiled in chemicals to bleach the inclusion, or it’s removed by burning it with the laser.
The dark spot inside is removed, but the tunnel formed to reach it is still there.
The most effective laser drilling ensures the hole is nearly invisible, it doesn’t remove significant weight from the diamond, and it isn’t at a higher risk of breaking.
So why should you avoid a diamond with laser drill holes?
A diamond with a laser drill hole is considered a clarity enhanced diamond.
While the inclusions are less visible to the naked eye, it does diminish its value. If you compared two diamonds that look similar, but one is clarity enhanced and the other is natural, the natural diamond would have a much higher price.
There’s a lower demand for clarity enhanced diamonds because most buyers don’t want their diamond artificially treated to improve its appearance.
A quality diamond that formed naturally is more valuable.
6. Knots
A knot inclusion is a crystal that penetrates the surface of a diamond. They’re discovered after the diamond is fashioned and often appear white or transparent.
The reason you should sometimes avoid a diamond with knot inclusions is because they’re visible to the naked eye and affect durability.
Eye-cleanliness is a valuable trait in a diamond, so any inclusion visible without magnification is bothersome to many buyers.
The reason knots are often visible is not because of their color but instead because they extend to the surface.
It looks like a raised area on one or many facets, and if you ran your finger along it, you might notice a slight bump.
7. Indented Naturals
An indented natural inclusion is often discovered right before the diamond hits the shelf.
During final preparation, diamonds are polished to remove the rough outer textures to allow more light to enter.
It’s here that indented naturals can be found near the girdle when there’s a dip below the polished surface. They’re a visible piece of the original surface of the diamond.
The reason this portion isn’t removed is it would require cutting carat weight off the diamond, and it would sell for a lower price.
This inclusion is similar to chips and cavities but causes less of a durability issue in comparison. But that doesn’t mean it’s free from that problem.
You should avoid a diamond with large or multiple indented natural inclusions because it leaves it more susceptible to breaking, and the indentations can fill with dirt and grime.
Are Inclusions Ever Beneficial?
Minor inclusions can be beneficial because they lower the price of the diamond.
Buying a diamond within your budget is about trade-offs. You need to decide which qualities are most important to you and sacrifice in other areas to reduce the cost.
The number, size, and type of inclusions is one area you should explore to find a diamond in your price range.
For example, this 1.08 carat round diamond (left) is flawless, meaning it has no visible inclusions, even with magnification. It costs $9,780.
As a comparison, this diamond has all the same qualities except its clarity grade is VS1, meaning it has inclusions likely only visible through magnification. It costs $6,900.
The buyer can save $2,880, or 42 percent, by selecting a diamond with inclusions.
This concept becomes more pronounced as you compare flawless diamonds with ones graded between I1 (included) and VS2 (very slightly included). The presence of more inclusions, especially ones that are visible, continues to lower the price all the way down the GIA scale.
My recommendation for clarity is to purchase an eye-clean diamond. In many cases, this means a clarity grade of SI or above. For larger diamonds, you may want to choose one with VS2 clarity.
Conclusion
Inclusions are an inevitable consideration in almost every diamond purchase. Flawless diamonds are a rare find, and the premium price turns away many buyers. That means most buyers are faced with the decision of which types of inclusions they’ll accept.
Avoid inclusions that significantly impact the durability, aesthetic, and light return of a diamond, and in many cases, this includes chips, dark crystals, long feathers, and more.
If you’re not able to view a diamond in person before buying, choose an online retailer that offers high-resolution photos of the exact diamond.
This gives you the information you need to know about how the inclusions affect its performance.
But by understanding the variety of inclusions you’ll encounter searching for the right diamond, you can be prepared to select the right one you know will last forever.
Jacob Clarke
Jacob Clarke is the founder of TeachJewelry.com.
He earned an Applied Jewelry Professional Diploma from the Gemological Institute of America (GIA) and now brings you essential information about diamonds, settings, and more.
Jacob has consulted with leading jewelry brands, and his work has been cited in Clean Origin, Diamond Nexus and industry publications.
He's also a member of the International Gem Society.
He enjoys discussing jewelry with readers, so contact him with any questions at jacob.clarke@teachjewelry.com.