Diamond buying is a complex combination of art and science. Navigating around the pitfalls is harder for those that know little about jewelry-grade diamonds, and the technicalities surrounding them. In this, as in many other things, educating yourself is of paramount importance.

First off, you need to understand that not all inclusions or imperfections are completely bad for your stone. Some of these can work in your favor as a consumer, and even if you could not rake up enough cash to avoid all of them at the time of purchase, they can perform the function of identifiers. No two stones are the same, but the things that make each different from its lookalikes, may not be easily apparent. Moderate spenders have a pretty good reason to be thankful for visible inclusions in their diamonds, especially if they are one of the following.

Pinpoints and Clouds

If a jeweler shows you a stone that has a pinpoint in it, you should know they are referring to a tiny mineral crystal present inside it. This sort of things is normally the size of a speck of dust, and is hard to spot even under magnification. A cluster of them would be more readily seeable, and when it shows up as a haze, it is called a cloud, because of the visual similarity to clouds you generally see in the sky.

Crystal, Knot, Needle, or Dark Crystal

A crystal is any mineral, sometimes a diamond, which is still embedded in a stone in its raw form. A dark crystal would have a dark or medium tone. A needle, meanwhile, is a long and narrow crystal in the shape of a rod. A knot is any crystal that reaches the outer surface of the stone, just like one in a wood grain. While it is rare, crystals can take on familiar or appealing shapes, such as that of a heart, a dolphin, or a bumblebee. They can be colorless, or occur in any shade of white, as well as a variety of other tones including red, gray, green, and black. A sensible owner would choose to see these simply as extra gemstones besides the one they paid for, which is a great way to look at it.

Feather or Cleavage

This looks a lot like a geological chasm, although it can only be seen under magnification. A feather, also called a cleavage, is no more than a separated plane or void inside the internal structure of the diamond. SI clarity diamonds may reveal any larger feathers they carry, even to the naked eye. I2 and I3 stones can have feathers that endanger structural integrity, which is one reason why many big jewelers do not trade such diamonds. In higher clarity stones, feathers are not much of a concern, expect cosmetically.

Twinning Wisps or Internal Grain Lines

Grain lines, even when they appear in groups, are slight growth patterns resulting from irregularities in the formation of a diamond. These are usually found to be colorless. Twinning wisp are strings of tiny clouds, pinpoints, or crystals, which are caused by structural irregularity. Both of these imperfections are caused naturally due to a single disruption to the stone’s million-year formation.

Indented Natural, Cavity, and Chip

Indented Natural inclusion is an indentation in the stone, coupled with some of the unpolished outer skin. An intended natural is always intentionally made around the girdle. Cavity is a tiny, deep concave area that forms as a result of a crystal close to the surface being removed during cutting or polishing. It may seem unsightly on close inspection, but can be a great way to identify a specific stone. Chips, on the other hand, are shallow and small opening that appear irregularly on the edge of a diamond’s girdle.

These are some of the inclusions, which you should be mindful of when buying diamonds. Remember, a stone graded over VS is probably going to be eye clean, and any inclusions that affect its clarity would be laid out in the accompanying GIA report. The main downside to that is significantly higher cost.

In the diamond industry, inclusion type is just one of the five factors that decide the clarity grade of a diamond. The others are size, position, number, color or relief, and nature. Again, unique imperfections are great identifiers, because just like snowflakes, diamonds are each unique. Knowing exactly what your stone carries is a great way to make sure you do not confuse it with someone else’s.

Another way inclusions are good is that when buying, they set natural diamonds apart from physically perfect manmade ones. A diamond created in a lab would not hold any of the above inclusions, but that fact also gives away its synthetic nature, which many buyers would rather not have a part of.