In this article, we discuss the 15 most obvious diamond inclusions to avoid. These range from man-made laser drill holes to those that are just downright ugly, caused by mother nature. Before we begin, it’s important to note that no matter how perfect a diamond appears to the unaided eye, most have “clarity characteristics,” a term that means tiny flaws and imperfections that are either inside the stone (inclusions), on the surface of the stone (blemishes) or both (surface reaching inclusions). Most of these clarity characteristics are so small they can’t be seen with the naked eye (“eye clean”), and many are even hard to detect with a 10X magnification jeweler’s loupe. So, while the list is extensive, it’s also unlikely that you will have one of the below (at least visible) if you stick with a diamond grade clarity of SI1 or higher.
It’s Not Just the Size and Type, it’s also the Location and Color
Let me begin by saying that not all diamond inclusions are created equal. An inclusion, set off to the side and in the pavilion on a round brilliant diamond has less of an impact on the clarity and rating of the stone (all else being equal), than the same inclusion directly under the table near the surface. The former is usually fine, the latter would be one of the diamond inclusions to avoid.
Similarly, an inclusion that is bright and glossy is far more of a problem than one that is semi-transparent. Both location, and color, are as important as size and type because when it comes right down to it, it’s about how easily it is to see the diamond inclusion.
Man Made Inclusions
I’m going to start off with inclusions caused by treatment (i.e., man-made inclusions).
Laser Drill Holes – sometimes an inclusion is just too obvious to ignore. A big black spec in the middle of the diamond, for example, can make an otherwise stunning stone look quite ordinary. The diamond industry has come up with a way to treat this problem using a tiny laser. The laser will cut a tiny tunnel to the inclusion, and an acid solution will be injected to bleach or dissolve the inclusion to make it disappear, or at least less visible. Most diamond grading labs will grade a laser drill holed diamond because this is a permanent inclusion.
Fracture Fillings – One way to cover up the laser drill hole is to inject molten glass into the hole. This method makes the drill hole hard to detect and is often only picked up when the diamond is sent in for grading. Fracture filled diamonds have a variation in color, called the “flash effect,” when the diamond is rocked back and forth under light. Reputable diamond grading labs will not grade a fracture filled diamond because the treatment is not permanent.
Mother Nature’s Inclusions
Mineral Crystals – There are more than 24 different mineral inclusions that might be found on the inside of a diamond. The most common are smaller diamond crystals, olivine and garnet. They result in:
- Needles (tiny long thin rods),
- Pinpoints (tiny dots), and
- Clouds (many tiny pin points grouped together).
Of these, clouds and needles have the greatest risk of creating an unattractive inclusion.
Crystal Distortion During Growth – Some inclusions are a result of an irregular crystal structure itself. These include:
- Twinning Whisps (flat and ribbon-like. They radiate out of the diamond’s center).
- Internal Graining (takes the appearance of lines, angles or curves and are white, colored or reflective in color).
- Grain Center (small, concentrated area of crystal growth distortion).
Surface Reaching Inclusions – These inclusions reach or touch the surface of a diamond, or extend from the surface into the stone.
- Feather (often shiny, white, and/or glossy. Some feathers “blink” from transparent to white when the stone is rocked),
- Etch Channel (angular opening that starts at the surface and extends into it),
- Bearded Girdle (minor feathers running perpendicular to a bruted girdle),
- Bruise (a tiny area of impact, followed by root like feathers),
- Knot (a diamond crystal that extends to the surface after the diamond is fashioned),
- Patch of Color (a green “radiation stain” caused by naturally occurring radiation during the diamond’s development process),
- Chip (a shallow opening on the surface),
- Cavity (opening on the surface after a feather breaks away), and
- Indented Natural (a portion of the diamond’s original surface that dips below the polished diamond’s surface).
The last three: chips, cavities and indented natural’s are difficult to distinguish from each other.
As I mentioned at the beginning, of this article, most diamonds have inclusions, including (most likely) your wealthy best friend’s new two carat perfect engagement ring. Each of the clarity characteristics above would affect a diamond’s grade, depending on size, color and placement. The smaller the size, the less centered the placement, the better the look of the diamond. Better looking diamonds have higher clarity grades, and most are not visible to the naked eye. Most importantly, they are identified on a GIA diamond grade certificate, so you don’t need to figure it out yourself.
Having a Little Fun with Diamond Inclusions to Avoid…
Our recommended online discount diamond store, James Allen, includes the diamond certificate on each stone that it offers, right up front as part of the digital inspection – before you buy. We recommend that you buy only GIA graded diamonds. There are many diamond grading labs, but GIA represents about 80% of the James Allen inventory. Below, find a hyper link matrix to James Allen’s inventory – GIA graded diamonds only. Across the top is the carat weight and down the side is the clarity value (worst at the top, best at the bottom – the top will likely contain many of the diamond inclusions to avoid). You can have some fun and see what some of the clarity characteristics above look like up close. More importantly, you can play with the 4C’s and find the perfect diamond for your price range. James Allen has over 13,000 diamonds in its online inventory and they are about 30-50% off retail prices.
(Worst to Best)
|I1||½ Carat||1 Carat||1½ Carats||2 Carats||3 Carats|
|SI1 & SI2||½ Carat||1 Carat||1½ Carats||2 Carats||3 Carats|
|VS1 & VS2||½ Carat||1 Carat||1½ Carats||2 Carats||3 Carats|
|VVS1 & VVS2||½ Carat||1 Carat||1½ Carats||2 Carats||3 Carats|
|Internally Flawless (IF)||½ Carat||1 Carat||1½ Carats||2 Carats||3 Carats|