Natural diamonds, in the process of being formed by carbon element through high temperature, high pressure underground environment, naturally feature internal and surface defects, called ‘inclusions’ and ‘blemishes’, respectively. Natural, tiny imperfections do not affect the beauty of the diamond. On the contrary, these traces make each diamond unique.

  

What is diamond clarity? How is it graded?

Diamond clarity is one of the criteria for judging a diamond’s quality. Diamond clarity is graded by Nature, Position, Size, Quantity and Relief of clarity characteristics and surface features. These characteristics are like each diamond’s "birthmark". Clarity refers to the purity of the diamond; the higher the clarity, the higher the value of the diamond.

As for the diamond inclusions, Pinpoint, Cloud, Crystal and Feather are common. The clarity of a diamond is graded using a 10x microscope and any inclusions that are detected at that magnification are generally not visible to the naked eye. At 10x magnification, almost no diamond is perfect, thus flawless diamonds are rare.

  

GIA Diamond Clarity Grading

Under the GIA Diamond Clarity Grading System, diamond clarity is divided into six levels, including Flawless (FL), Internally Flawless (IF), Very Very Slightly Included (VVS), Very Slightly Included (VS), Slightly Included (SI) and Included (I). External defects, on the other hand, refer to external impurities or imprints on a diamond's surface, which have a very subtle effect on its hardness and structure. As such, the impact of blemishes on a diamond's value, aesthetics and clarity level is generally small.

 

• Flawless (FL) - Observed under a 10x magnifying glass, the diamond has no inclusions or blemishes.
• Internally Flawless (IF) - Observed under a 10x magnifying glass, the diamond has no visible inclusions, only visible blemishes that only professional graders can see.
• Very Very Slightly Included (VVS1 and VVS2) - Observed under a 10x magnifying glass, the diamond’s inclusions are difficult even for a professional grader to see.
• Very Slight Included (VS1 and VS2) - Observed under a 10x magnifying glass, the diamond’s tiny inclusions range from difficult to see by professional graders to easier to see.
• Slightly Included (SI1) - The diamond’s inclusions can be easily seen when viewed under a 10x magnifying glass, but most do not affect the front appearance and transparency of the diamond.
• Slightly Included (SI2) - Observed under naked eye, the diamond’s inclusions are visible, but most do not affect the front appearance and transparency of the diamond.
• Included (I1) –The diamond’s inclusions are clearly visible by naked eye and may affect transparency and brightness.
• Included (I2 and I3) - The diamond’s inclusions are clearly visible by naked eye, and affect its transparency. Diamania does not sell diamonds at this clarity level.

 

GIA Diamond Grading Report for a one carat or above diamond is accompanied by a plotted diagram of its clarity characteristics. Markings in red represent internal inclusions, while indications in green represent external blemishes. This diagram serves as a very useful tool for distinguishing diamonds. In general, only inclusions which have a significant impact on a diamond’s clarity level will be indicated, while other inclusions will only be noted in the comments.

 

Here is a list of the characteristics that may appear on a plotting diagram, along with their corresponding symbols:

 

  

Types of inclusions

There are many types of inclusions, and the following are enlarged images and notes for each inclusion:

 

 

Crystal - Minerals hidden inside diamonds are the most common inclusions and can manifest in different sizes and colors.

 

 

Pinpoint - Tiny dots of crystals in a diamond are the slightest and most common inclusions.

 

 

Cloud - A cluster of pinpoints which are common inclusions. Each pinpoint in the cloud is too small to be individually discernible; however, serious ‘Cloud’ conditions can cause a diamond to have a hazy (“milky”) appearance. (Diamania does not sell “milky” diamonds)

 

 

Needle - A slender crystal shaped like a needle. This is a common, though very slight inclusion.

 

(The above four inclusions are caused by the mineral crystal, with differences in size, shape and range.)

 

  

Feather - A crack in the diamond which resembles a feather. Most of these common types of inclusions are minor. Large cracks (generally Si2 or below) have a risk of becoming larger and of having an impact on the structure of the diamond.

 

  

Knot - Another transparent diamond crystal touching the diamond facet. It is generally more common in SI-graded diamonds.

 

  

Cavity - A Corner Notch which may have been caused by the collapse of a small piece of diamond. It may also be a pit or hole caused by a crystal shedding on the surface of a diamond during the polishing process. It is generally more common in SI-graded diamonds.

 

  

Bruise - A mark formed by external force impact that extends from the surface of a diamond to the inside, generally seen at the junction of the facets. It is usually white, accompanied by cracks, and is relatively rare.

 

  

Natural - Where most of the rough stone skins retained at the girdle or near the girdle for maximum quality are irregular. More common in just 0.7cts, 1.0cts and 1.5cts.

 

 

Indented Natural - Part of the rough stone skin is sunken under the surface of the cut diamond, which is more pronounced than natural. It is more common in just 0.7cts, 1.0cts and 1.5cts.

 

  

Twinning Wisp - The center point of the crystal structure irregularity of the diamond, often accompanied by pinpoint inclusions. Generally more common in SI-graded diamonds.

 

  

Internal Graining / Surface Graining - These diamond growth marks are due to irregular growth of atoms.

 

  

Bearded Girdle - A whisker-like microcrack that exists at the girdle and looks like a beard. It is caused by excessive rough grinding and is rare.

 

  

Laser Drill Hole -  A microscopic tube that is present as a result of laser drilling. The process of laser drilling involves using laser to drill tiny holes all the way from its surface to an inclusion. This channel is then used to remove the inclusion by either melting with heat or dissolving with acid.

 

  

Etch Channel - A strip-shaped like a saw or a knife that extends from the surface. It goes from the surface to the most vulnerable position in the body of the rough by chemical or material erosion. It can be straight or curved and can be deep. Shallow versions are less common.

 

According to statistics, most customers will purchase diamonds with a clarity grading of VS or SI. However, if you intend to choose a diamond from diamonds with the same clarity grade, it is important to pay attention to the distribution and characteristics of the inclusions prior to purchase. For example, dispersed inclusions are more popular. If you wish to find the diamond that suits you best, you are welcome to make an appointment for a free consultation with Diamania.

 

Eye Clean - A diamond classified as ‘Eye Clean’ looks clear to the naked eye; i.e. its inclusions are not visible on the front side without the aid of a magnifying tool. Since each person's vision is different and the guidelines are different, this definition is more subjective. Generally, diamonds are viewed from about six inches away by the naked eye. If the front side does not appear to have obvious inclusions, it may be called Eye Clean.

 

Almost all diamonds contain inclusions while traces of inclusions in diamonds of FL and IF grades are not detectable at 10x magnification. Many customers believe that VS and SI grades have the highest cost-performance ratio, because these grades are more affordable, meanwhile the inclusions and blemishes of VS and SI grade diamonds are typically not visible by naked eye. The brightness of a diamond may also be affected by the visibility of the inclusions and blemishes. The larger the facets of the diamond (such as an Emerald-cut diamond), the easier it is to examine its inclusions and blemishes. It follows then that if you want to buy a diamond with a large table or fewer facets, it would be wiser to select a clarity grade of VS or above.