The Four C’s – Clarity
Clarity grading is perhaps the most subjective process of the 4C’s. The clarity of a diamond is a way of representing how clear a stone is, or how much junk is “floating” inside the crystal. If you can see a lot of stuff inside the diamond, then the clarity grade would be very low. Likewise, if you cannot see anything inside the diamond…like clear water…then the clarity grade would be very good. The clarity of a diamond is graded at 10x power, either using a 10x loupe, or through a microscope set at 10 power. This helps standardize the process. Obviously, if I grade a stone at 10x, and then you come along and grade the same stone at 20x, then you will see much more inside the stone than I was able to see. Thus, the stuff which I could see would look much worse to the 20x observer than to me and coupled with the stuff that I could not see, would result in a different grade than I would have given at 10x. And although clarity grading is very subjective, it is possible to refine the process through training and standardized procedures, such that any group of gemologists, grading the same stone, should be within one clarity grade of each other.
There are eleven clarity grades established by the GIA:
- IF — Internally flawless;
- VVS1 & 2 — Very, very, slightly included;
- VS1 & 2 — Very, slightly included;
- SI1 & 2 — Slightly included;
- I 1,2, & 3 — Included.
Flawless diamonds are…by definition…flawless…at 10x. Thus no inclusions of any sort can be found while grading at a 10 power magnification. This also extends to polish marks, surface graining, and other surface related blemishes.
Internally flawless, IF, stones, are essentially the same as a flawless stone, except they have some very small surface blemish that could be removed by polishing or very minor recutting.
VVS diamonds are those that have inclusions that are very minute, and require close inspection even for a trained expert to find them.
VS diamonds are those that have inclusions that are very minor, but are not as difficult to find by a trained expert as those in a VVS stone.
SI diamonds are those that have inclusions that are somewhat minor, but are not as difficult to find as those in a VS stone and can be found by someone not specifically trained in diamond grading.
Included diamonds are those that have inclusions that are somewhat easy to find, and can easily be found by someone not specifically trained in diamond grading. The inclusions in this category are such that they can, and in the case of I2 and I3 grades, actually do affect the integrity/durability of the stone.
There are many things that can be found inside a diamond crystal that would be considered as an inclusion. Two of the more common inclusions are feathers and crystals. Feathers, which are very small cracks or fractures, which can either reach the surface of the crystal or be fully contained inside the crystal and do not reach the diamonds surface, are one of the more common inclusions. These usually do not pose any danger to the durability of the stone unless it is graded as an I1,2 or 3. Crystals of other minerals can also get trapped inside a diamond during the time when it is being formed, and can result as an included crystal inside the diamond. These can look like black spots inside the diamond and are often incorrectly referred to as “carbon spots”.
The vast majority of diamonds sold in the world are VS / SI grade stones, with the biggest majority of those being SI grade. Some within the trade have added a SI3 grade, but this is not an “official” grade in the GIA’s system, and will never be used on any GIA grading report. More and more, I1,2,and 3 graded stones are being routinely used in jewelry items where they have never been used before. Very often, the deeply discounted diamond jewelry products that proliferate the newspaper ads and other venues, are actually these “I” graded diamonds. Caveat Emptor…let the buyer beware…very definitely applies here. The old adage…”you get what you pay for”… holds particularly true in situations such as this.