CUT
Cut is the most objective and scientific measurement of a diamond’s proportions, arrangement and alignment of the facets, and quality of the polish. In an ideally cut stone, the light entering the diamond reflects and refracts creating the fire, brilliance, and scintillation (“sparkle”) in the stone. The Cut is a result of the artistry and craftsmanship of the diamond cutter, to maximize the return of light.
Cut Vs Shape
Of the 4 Cs, the "Cut" is the most crucial component to a particular stone’s overall beauty. The Cut should not be confused with the “shape” of a diamond.
The Cut is only measured for Round Brilliant diamonds. All other shapes do not receive a “Cut” grade, but rather a polish and symmetry grade.
The “Cut” is therefore more subjective for these shapes, and the beauty of the stone is more subject to the overall “look” that the client is trying to achieve.
Color
Color is generally considered the second most important attribute when selecting a diamond. This is because it’s usually the most noticeable characteristic, aside from size. A diamond’s color grade refers to the presence or lack of “tint” in the diamond. In a white diamond, this would be a presence or lack of yellow.
The Gemological Institute of America (GIA) grades diamond color on a scale from D to Z. While most diamonds appear to have no color to the untrained eye, most stones usually contain slight tones of yellow. The rule of thumb is that you need to jump two color grades to see a noticeable difference in color.
Diamonds in the D-to-F range are considered “Colorless”; these stones are the most rare, and therefore the most valuable.
Diamonds in the G-to-H range are considered “Near Colorless” and can offer more “value” with regards to pricing.
Diamonds in the I-to-J range are defined by having “Noticeable Color”. This is definitely subjective, and stone-specific.
For most shapes, we consider J to be the cutoff before yellow is “too noticeable”. Some shapes are better at hiding color than others; for example the Round and Emerald camouflage color much better than a Cushion, Pear, or Oval would.
Note: Colored diamonds (other than yellow) are valued gemstones. These diamonds have a distinct color grading system from “white” diamonds.
Carat
The Carat is a measurement of how much a diamond weighs. Each Carat is divided into 100 “points”. For example a half-Carat stone is considered a “50 point diamond”. All else being equal, diamond price increases with Carat weight because larger diamonds are more rare, and thus harder to source.
When looking for a diamond, Carat should be used as a guideline but not the determining factor in your selection. Carat is not necessarily the best indication of how large a stone will appear, rather the measurements of the diamond are a more important reflection of “size”.
The Carat selection for your diamond purchase will generally be determined by your budget, so it’s best to set parameters for your price range, assess a range of qualities (Color/Clarity), and then find your preferred balance between size (Carat) and quality (Color/Clarity/Cut).
Clarity
A diamond’s Clarity grade is based on the number, size, and location of the imperfections that naturally occur in a diamond. Most imperfections tend to be microscopic and generally do not affect the overall beauty of a stone. These inclusions are natural identifying marks that occur during the diamond formation process. Clarity is graded on a scale ranging from Flawless to Included, and the visibility of the imperfections are graded under 10x magnification.
When selecting a diamond, the buyer will determine if he/she is comfortable with the imperfections in a particular stone, since every diamond will have a different occurrence of imperfections. It is best to assess clarity with the naked eye first, before looping the stone to evaluate the imperfections under magnification. Once a diamond is purchased and set into a piece of jewelry, it is rarely viewed under magnification, so we encourage our clients to make a purchase based on the “naked eye” view.
The “safe zone” for clarity in a Brilliant diamond would be VS2 or above, while in a Step-cut diamond, it would be VS1 or above. Generally speaking, we advise that if the stone appears to be “eye clean” (one cannot see imperfections to the naked eye), there is a lot of value to be found in a SI1 or even SI2 quality stone.
