Grading Scale
While diamonds are graded using the system devised by the Gemmological Institute of America (GIA) in the 1950s, there is no standardized or universally accepted grading system for colored stones like rubies, sapphires, emeralds, etc. Historically, it has always been a general practice to grade colored stones with the unaided eye. However, we have devised a grading scale, on the basis of the diamond grading scale, which is easy to understand and not only takes into consideration appearance with the naked eye but also the appearance under 10x magnification (i.e. a jeweler's loupe).
CLARITY GRADING SCALE
Detailed Clarity Grading Scale on the Basis of which the Colored Stones listed in our store are graded (the first one being the best and the last one being the lowest grade)
Grade |
Eye-Clean / Loupe-Clean (10x) |
Detailed Description |
IF (Internally Flawless) |
Eye-Clean, Completely Loupe-Clean |
No inclusions visible under 10x Magnification |
VVS1 (Very Very Slightly Included 1) |
Eye-Clean, Loupe-Clean |
Minor Pin-Point Inclusions visible under 10x Magnification |
VVS2 (Very Very Slightly Included 2) |
Eye-Clean, Loupe-Clean |
Minor Pin-Point Inclusions visible under 10x Magnification |
VS1 (Very Slightly Included 1) |
Eye-Clean, Near Loupe-Clean |
Minor Inclusions visible under 10x Magnification |
VS2 (Very Slightly Included 2) |
Eye-Clean, Near Loupe-Clean |
Minor Inclusions visible under 10x Magnification |
SI1 (Slightly Included 1) |
Eye-Clean, Not Loupe-Clean |
Inclusions visible under 10x Magnification but not with unaided eye |
SI2 (Slightly Included 2) |
Near Eye-Clean, Not Loupe-Clean |
Inclusions visible under 10x Magnification and also with unaided eye (minor) |
SI3 (Slightly Included 3) |
Not Eye-Clean, Not Loupe-Clean |
Inclusions visible under 10x Magnification and also with unaided eye (considerable) |
I1 (Included 1) |
Visibly Included |
Inclusions visible under 10x Magnification and also with unaided eye (heavy) |
I2 (Included 2) |
Visibly Included |
Inclusions visible under 10x Magnification and also with unaided eye (very heavy) |
Semi-Transparent |
Varies from stone to stone |
Not Completely Transparent neither Completely Translucent |
Milky-Transparent |
Varies from stone to stone |
Transparent but with milkiness |
Translucent |
Varies from stone to stone |
Allowing light to pass through but not transparent |
Opaque |
Varies from stone to stone |
Not allowing light to pass through |
Note: The numbers denote the intensity of inclusions i.e. the intensity of inclusions in a stone with VVS2 clarity would be more than those in a stone with VVS1 clarity.
GENERAL GRADING SCALE
Gemstones are also graded on a scale from “A” to “E” by our gemmologists based on the overall appearance and after taking into consideration the combination of the following criteria:
- General Rarity
- Clarity Grade, intensity of inclusions and effect of inclusions on the overall appearance of the stone
- Hue, Tone and Saturation of Colour
- Cutting Grade
- Origin
- Appearance of the gemstone in relevance to the general appearance of stones in that particular group
This is a general grading scale which divides all gemstones into 5 parts depending on a variety of factors. A Majority of the stones listed on the store are grade “A” and grade “B” stones since we list very few grade “C’, “D” and “E” stones.
Also See: Gem Certification