Even though the world of diamonds and the world of colored gemstones share only the most basic of similarities, some of the grading of diamonds sneaks into the colored gem terminology used for tourmaline. The most egregious is the use of the whole list of acronyms such as VS1 (very small one) and VVS2 (very very small 2) etc. This clarity scale ignores the placement of the inclusion, its reflectivity, and orientation. I am not saying that VVS2 and VS1 don’t indirectly address the visibility of flaws (with a 10 power loop), but the wide range of tone values inclusion sizes even in some high-quality color gems renders the counting of the number of inclusion completely. inadequate. The tendency of some colored gems to be translucent and still be faceted is also not adequately addressed in diamond grading.
Here are my thoughts on tourmaline gemstone clarity grading.
The clarity scale I ascribe to and use for tourmaline in the colored gem world revolves around, eye clean, an obnoxious flaw that significantly decreases the beauty of the gem, quality of the gems crystal, and the physical integrity of the gem. I will try to clarify my position in the following paragraphs.
1, Eye clean: I work with a 7 power loop when I cut and polish the gemstones in my collection. I see many features in the tourmaline gems face up or from any reasonable angle that can not be seen by the eye. If you can not see it with the naked eye in the finished gem face up or at a reasonable angle the gem is considered eye clean. Any quality issues concerning tiny weaknesses in the gem are addressed by other criteria.
2, Obnoxious flaws: Judging a flaw in the tourmaline as obnoxious or not is certainly a personal decision. With some rough, I spend a significant amount of time orienting flaws so I can lessen their effect on the beauty of the finished gem. Success in this effort is one of the most satisfying aspects of faceting for me. What I am getting at is my sensitivity to flaws and their crucial nature to the beauty of natural gems is not forgotten in my critical appraisal of the gems in my collection.
3, Crystal quality: The brightness and crispness of a gem can be affected by the cutting and polishing of the gem and its intrinsic nature. With crystal quality, I am talking about the intrinsic hazy nature (lack of transparency) of the material at the molecular level. It is easy to see variations in tourmaline crystal quality when you have gems with similar characteristics to compare them with.
4, Physical integrity. Some gems are stressed by irradiation, heating, chemical composition, and its changes, flaws, and cutting. High-stress levels from all these factors can lead to breakage while the gem is being set and afterward. Tourmaline in particular carries internal stress which can cause unexpected breakage. Proper efforts to cut a strong gem, that can be controlled by the cutter, can be seen in a good girdle (principally thickness.) and a reasonable crown thickness. Disappointments will still occur in even apparently strong gems.
Please think in terms of the color world with my collection.