1. A key factor in distinguishing good and bad moissanite grades: Luster
Moissanite is categorized into eleven grades based on lustre, from highest to lowest: D, E, F, G, H, I, J, K, L, M, and N. The closer a moissanite is to D, the closer its lustre is to colorless. Moissanite comes in a variety of colors, especially transparent, colorless ones, which allow light to pass easily and create a vibrant display after refraction and scattering. Moissanite lustre grading is determined by professionals in a professional laboratory setting, who continuously compare graded moissanite with standard lustre and colour. From highest to lowest, there are five grades: very white, excellent white, white, pale yellowish white, and pale yellowish. White and pale yellowish white are generally the most common.
2. Moissanite Grading: A Key Distinguishing Factor Between Good and Bad: Weight
Moissanite is measured based on diameter, and its weight is converted to carats (c). 1 gram = 0.2 grams = 100 points. Generally, carats above 10 points are marked with a moissanite grade. Because moissanite's composition differs slightly from diamond, it is 10% lighter than diamonds of the same size. Therefore, moissanite is sold based on size rather than weight. A moissanite with a table diameter of 65mm can fit perfectly in the setting of a 1-carat diamond ring, yet it actually weighs only 0.88 carats. If you choose a moissanite by weight, you'll find it's 10% larger than expected.
3. Moissanite Grading: A Key Factor for Good or Bad Moissanite: Clarity
Moissanite is categorized into eleven grades based on clarity, from highest to lowest: FL, IF, VVS1, VVS2, VS1, VS2, SI1, SI2, I1, I2, and I3. Moissanite closer to the FL grade has fewer imperfections. The complex cultivation process of moissanite inevitably results in inclusions and imperfections within its internal structure. The color, number, size, and location of these inclusions reflect varying degrees of clarity. Clarity grades of VVS1 and VVS2 indicate only very slight inclusions. Minor inclusions are visible under 10x magnification, and only a small number of moissanite diamonds meet these strict quality standards and are therefore classified into different grades.
4. Moissanite Grading: A Key Factor for Good or Bad Moissanite: Cut
The cut quality of moissanite encompasses three dimensions: cut, polish, and symmetry. A good cut maximizes the brilliance and fire of a moissanite while preserving the original stone's weight. Moissanite cuts are categorized into five levels: EXCELLENT, VERYGOOD, GOOD, FAR, and POOR. Cut is further divided into cut proportion, polish, and finish. A moissanite with an EXCELLENT grade in all three is considered excellent. Moissanite cut quality is the primary requirement of the 4Cs standard. Professional care is a key factor in enhancing the natural beauty of a moissanite, and therefore, cut quality can be considered its "second life."
