DIAMOND CLARITY
With clarity, we describe a diamond's purity. As they are a product of nature, all natural diamonds have traces of their growth history. In gem quality diamonds these are minor internal characteristics. Since diamonds form under extreme heat and pressure, internal and external characteristics are common. These characteristics help gemologists separate natural diamonds from synthetics and simulants, and identify individual stones.
There are two types of clarity characteristics: inclusions and blemishes. In order to grade the clarity of a diamond, it is necessary to observe the number and nature of external and internal characteristics of the stone, as well as their size and position. The difference is based on their locations: inclusions are enclosed within a diamond, while blemishes are external characteristics. The clarity scale reflects the size, number and location of the characteristics when examined with a 10 x loupe. Diamonds that have no inclusions visible to the naked eye are of excellent quality. Diamonds which contain numerous or significant inclusions or blemishes have less brilliance because the flaws interfere with the path of light through the diamond.
Diamond cutters make every effort to cut a stone so that inclusions are not visible through the table of the finished diamond. The preferred position for inclusions is under the bezel facets or near the girdle because they are harder to see there.
IDR provides plotted diagrams of clarity characteristics marked in red for internal and green for external features. In grading diamond clarity, the IDR considers the number, size, color, reflectivity, and position of every flaw visible under 10x magnification.
Below is the IDR diamond clarity chart with definitions, accompanied by further explanatory comments:
There are two types of clarity characteristics: inclusions and blemishes. In order to grade the clarity of a diamond, it is necessary to observe the number and nature of external and internal characteristics of the stone, as well as their size and position. The difference is based on their locations: inclusions are enclosed within a diamond, while blemishes are external characteristics. The clarity scale reflects the size, number and location of the characteristics when examined with a 10 x loupe. Diamonds that have no inclusions visible to the naked eye are of excellent quality. Diamonds which contain numerous or significant inclusions or blemishes have less brilliance because the flaws interfere with the path of light through the diamond.
Diamond cutters make every effort to cut a stone so that inclusions are not visible through the table of the finished diamond. The preferred position for inclusions is under the bezel facets or near the girdle because they are harder to see there.
IDR provides plotted diagrams of clarity characteristics marked in red for internal and green for external features. In grading diamond clarity, the IDR considers the number, size, color, reflectivity, and position of every flaw visible under 10x magnification.
Below is the IDR diamond clarity chart with definitions, accompanied by further explanatory comments:
IDR DIAMOND CLARITY SCALE:
FL |
Flawless: No inclusions or blemishes are visible to a skilled grader using 10x magnification. |
Extremely rare, less than 1 in 5000 jewelry quality diamonds are rated FL. |
IF |
Internally Flawless: No inclusions, only blemishes are visible to a skilled grader using 10x magnification. |
FL and IF diamonds appear identical unless viewed under 10x magnification by a skilled grader. Less than 3% of jewelry quality diamonds are rated IF. |
VVS1 - VVS2 |
Very, Very Slightly Included: Inclusions are difficult for a skilled grader to see under 10x magnification. |
|
VS1 - VS2 |
Very Slightly Included: Inclusions are clearly visible under 10x magnification but can be characterized as minor. |
Inclusions are not visible to the naked eye. Perhaps 1 in 100 untrained observers can detect VS2 inclusions with the naked eye, on close inspection under ideal conditions. |
SI1 - SI2 |
Slightly Included: Inclusions are noticeable to a skilled grader using 10x magnification. |
SI1 is the lowest grade with flaws often invisible to the naked eye. SI2 inclusions are usually visible to the naked eye, although they will require close inspection. |
I1 |
Included: Inclusions are obvious under 10x magnification and may affect transparency and brilliance. |
I1 diamonds have inclusions that are almost always visible to the naked eye. |
© IDR ( INTERNATIONAL DIAMOND REPORT ) 2021