Loose diamond clarity is a very tricky business. There are many, many factors which make up what some would call the perfect diamond. For the purpose of this post, we will focus on clarity. The goal of this post is to put forth information in regards to how a diamond is graded for clarity and why it would receive a certain grade. This will also lead to a better understanding of the clarity you may wish to purchase for your diamonds.
HOW TO GRADE CLARITY
Clarity is graded in a given gem laboratory such as GIA by an accredited diamond grader. The grading is based on the diamond being in the upright position, with the top portion facing towards the grader. The loose diamond is viewed at a 10x magnification. This is important because any detail recorded at a greater distance should not count towards the clarity grade.
TYPES OF INCLUSIONS
There are a variety of inclusions or blemishes found in the crystal of a given diamond. These imperfections will count towards the overall clarity grading. The imperfections will range from something that looks like a white feather, a salt and pepper like formation, or a big black oil patch. In some instances, it is possible to find another diamond crystal of a different colour forming within the diamond. The blemish could be red or orange etc. This is because loose diamonds are formed under such high pressure under the earth’s surface and sometimes other materials mix into the diamonds structure. Rarely will you find a Type IIa diamond mined in the earth. A Type IIa diamond is has zero or close to zero impurities and makes up about 1-2% of total mined diamond production. Thus, in most cases, diamonds will have some type of inclusion.
Placement of the inclusion is also very important. If an inclusion is found in the centre of a diamond under the main or table facet, it will be more noticeable. It is also graded more harshly. Conversely, an inclusion found to the edge or girdle of the loose diamond will be graded more leniently as it is less obvious and more easily hidden under lots of facets. Thirdly, if an imperfection is too low, it will reflect in some instances all around the given diamond. This causes the inclusion to look more apparent which also receives a harsher grading.
Size is a very important factor in determining with a given stone is either graded as VS2 or SI2. If the inclusion covers a certain amount of space in the diamond, it will automatically receive a grading of Internally flawless to I3. Keep in mind, the decisions of loose diamond grading are done by an individual grader. This means that there is still room for error.
To summarize, we would advocate for balance. Find a nice inclusion such as a semi-transparent white feather, preferably off to the side near the girdle. Make sure the inclusion does not reflect around the entire diamond and can be covered completely or partially by a prong on the engagement ring you choose. Remember, every diamond is unique and it is important to evaluate each one on its own individual merits.
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