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Diamond Grading

A diamond's cost depends upon objective characteristics popularly known as the 4C's: Color, Clarity, Cut and Carat. The relationship between these four characteristics determines the value of a diamond. Our diamond grading charts will help you visualize the relationship between rareness and cost. Although it is commonly assumed that carat is the most important member of the 4C's, color, cut and clarity have a much greater impact on the appearance of a diamond.

Diamond Color Grades

When shopping for a diamond, it is generally preferred to choose a stone with the least amount of color possible. Diamond color is divided into five broad categories.

Colorless Diamonds (D-F):
Diamonds within the colorless range are the most rare and valuable of all those on the color scale. D/E color stones display virtually no color, whereas F colored diamonds will display a nearly undetected amount of color when viewed face down by a gemologist.
Near Colorless Diamonds (G-J):
Diamonds within the near colorless range appear colorless in the face up position, but do display a slight amount of color when viewed face down against a perfectly white background. This trace amount of color will be undetectable to an untrained eye once the diamond has been mounted. Near colorless diamonds offer a tremendous value for their price.
Diamond color grading chart

Diamond Clarity Grades

The GIA has provided us with a universally understood method of describing clarity grades for diamonds. There are five main clarity grades that can be found on your GIA or AGSL report.

  • FL/IF Diamonds:
    Flawless: No inclusions under 10x magnification.
    Internally Flawless: No or only insignificant surface blemishes and no inclusions when examined under 10x magnification. Normally, most blemishes can be removed by minor polishing. Very rare, beautiful and expensive diamonds.
  • VVS1/VVS2 Diamonds: Very Very Slightly Included: Contain minute inclusions that are extremely difficult for an experienced grader to locate under 10x magnification. VVS diamonds are considered very rare and beautiful.
  • VS1/VS2 Diamonds: Very Slightly Included: Contain minor inclusions that range from difficult to somewhat easy to see under 10x magnification. Typical VS inclusions are small crystals, feathers or distinct clouds. In some rare cases, a VS stone can contain an eye–visible inclusion. Excellent quality diamonds.
  • SI1/SI2 Diamonds: Slightly Included: Inclusions are easily visible under 10x magnification to an experienced gemologist and may be visible with the unaided eye. A great value.
  • I1/I2/I3 Diamonds: Included: Diamonds with significant inclusions.
Diamond clarity grading chart

Diamond Cut Grading

A diamond's cut not only refers to its shape, but also how effectively the stone can return light back to the viewer's eye. A well-cut diamond will appear very brilliant and fiery, while a poorly cut stone can appear dark and lifeless, regardless of its color or clarity.
Each and every diamond has its own unique set of properties and proportions:

  • Diameter: Width of a polished stone, measured from edge to edge.
  • Table: Largest polished facet located on the top of the diamond.
  • Crown: The top part of a diamond extending from the table to the girdle.
  • Girdle: The very edge of the diamond where the crown and pavilion meet.
  • Pavilion: The bottom part of a diamond extending from the girdle down to the culet.
  • Depth: The total height of a diamond measured from the table to the culet.
  • Culet: The small or pointed facet at the very bottom of a polished stone.
Diamond Clarity Grades Description
FL = Flawless & IF = Internally Flawless No visible flaws can be seen under 10x magnification
VVS1 & VVS2 = Very Very Slight Inclusions Inclusions are present, but are almost never seen under 10x magnification.
VS = Very Small Inclusions Inclusions are visible under 10x magnification, but only viewable an experienced gemologist.
SI1 & SI2 = Small Inclusions Inclusions easily visible under 10x magnification to an experienced gemologist and may be visible to the naked eye.
I1 - I2 - I3 = Imperfect Significant inclusions, visible to the naked eye, which may dim the diamond's brilliance.
Diamond cut grading chart

Diamond Weight Grades

The size of a diamond is proportional to its carat weight. When rough diamonds are cut and polished into finished diamonds, as much as 2/3 of the total carat weight may be lost. Since larger rough gems of high quality are found less frequently than smaller rough gems of high quality, a single two carat diamond will be more expensive than two one –carat diamonds of the same quality.

Diamond carat grading chart

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