Ideally, a diamond should be flawless. However, nature did not custom-make every diamond to be the perfect stone we want it to be. While some stones are nearly flawless, and as a result, come with quite heavy price tags, most are not.
Sometimes the flaws or imperfections are internal, visible only with the assistance of a magnifying tool, and other times they are external, becoming apparent to the naked eye. It is important to learn a bit about the various imperfections a diamond can have so that when you encounter a diamond that contains “flaws,” you can have a better understanding of what that really means.
External Blemishes
Inclusions that can be seen on the table of a diamond, whether a spot or a cut, are quite obvious and hard to miss. Even if they are extremely small, they are detectable when looked at closely. Though these types of imperfections bring down the price of a diamond drastically, most people would not want to have such flaws on their engagement ring, or any other jewelry piece for that matter. However, external blemishes can often be removed through the polishing process and are only sometimes kept in order to preserve the carat weight.
Some of the various external blemishes include abrasions, burn marks, extra facets, natural inclusions, nicks, pits, polish lines, scratches, and surface graining.
Abrasions are small marks along the diamond’s surface
A burn mark is a white or foggy facet caused by overheating the stone.
An extra facet is one or more additional facets.
A natural inclusion is not really an inclusion, just a section of the diamond that remains in its rough state without a polish or finish. This happens when a diamond cutter tries to avoid losing part of the carat weight.
Other inclusions, similar to the natural inclusions, were caused purposely or through the cutting process.
A nick is a mark placed on a rough diamond in order to indicate where to cut.
Pits are tiny openings that look like white dots.
Polish lines are lines or scratches left over from the polishing.
A scratch, just as it sounds, is a small scratch on the external part of the stone.
Surface graining is when there are parallel lines on the surface of the stone.
Internal Flaws
When coming across a diamond with internal flaws, it is important to know that this does not mean you must run from it. Sometimes internal imperfections can barely be seen even with a magnifying instrument. Additionally, when diamonds contain flaws, they generally cost less. If a diamond can cost less with an imperfection that is not even detectable to the naked eye, it could be to the buyer’s benefit. It all depends on the type of flaw, its size, and its location.
Internal flaws may be one of several inclusions. These include clouds, chips, feathers, graining, natural indentations, bruises, cavities, cleavages, knots, laser drill holes, needles, pinpoints, twinning wisps, and beards.
A group of many microscopic inclusions in the diamond are called a cloud.
A chip is when there is a small fragment of the stone either cut or knocked out of place.
A feather is a small fracture inside the stone that looks like a feather.
Additional internal crystals that create a foggy appearance are known as graining.
When a piece of the stone penetrates within the diamond it is called indented.
Bruises can be caused as a result of a fierce knock. This results in minimal surface crumbling.
A cavity is a small hole in the stone.
Cleavage is a crack in the stone that opens wider in one direction.
Knots often project externally, and are essentially minerals that go against the grain of the stone.
Laser drill holes sometimes occur when a procedure is done to melt down black inclusions. The procedure leaves microscopic drill tunnels.
Needles are very long and thin internal marks.
A pinpoint inclusion looks like the damage a pin would cause.
Twinning wisps are internal lines that look like internal black ripples.
Beards are small streaks that reach from the diamond’s surface to the middle of the stone.
Imperfections, whether external or internal, contribute to the diamond’s clarity. The term clarity is used so loosely, many are not even aware of what it involves. Once you know more about the imperfections a diamond can have and what the implications are, you can come to a more educated decision regarding your diamond purchase.
