Diamonds

THE 4 Cs OF DIAMOND CLASSIFICATION

THE ENCHANTMENT SURROUNDING DIAMONDS ENGAGES EVERYONE IN A DIFFERENT WAY. HOWEVER, WHEN ASSESSING THE VALUE OF A STONE, EVERYONE REFERS TO THE FOUR Cs, AS EXPLAINED BY THE GEMOLOGICAL INSTITUTE OF AMERICA (GIA): CUT, CARAT, COLOR, AND CLARITY.

WHEN THE DIAMOND SHOWS ITS TRUE COLORS

Color refers to the hue of a diamond. Slightly colored stones are most common in nature. Among the most coveted diamonds are those classified as colorless. These diamonds allow white light to effortlessly pass through, thus generating the fascinating rainbow effect. The color grade of a stone, from D (colorless) to Z (light yellow or brown), is determined by a comparison to “master stones”. Natural, colored diamonds – such as yellow, pink, or blue – are among the rarest and, thus, most valuable stones.

Diamond Clarity Refers to the Absence of Inclusions and Blemishes

Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called 'inclusions and external characteristics called 'blemishes

blemishes

Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher its value.

examples of how Clarity characteristics are plotted on a GIA Diamond Grading Report

The GIA Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades.

Flawless (FL)
No inclusions and no blemishes visible under 10x magnification
Internally Flawless (IF)
No inclusions visible under 10x magnification
Very, Very Slightly Included (VVS₁ and VVS₂)
Inclusions so slight they are difficult for a skilled grader to see under 10x magnification
Very Slightly Included (VS₁ and VS₂)
Inclusions are observed with effort under 10x magnification, but can be characterized as minor
Slightly Included (SI₁ and SI₂)
Inclusions are noticeable under 10x magnification
Included (I₁, I₂, and I₃)
Inclusions are obvious under 10x magnification which may affect transparency and brilliance

Many inclusions and blemishes are too tiny to be seen by anyone other than a trained diamond grader. To the naked eye, a VS₁ and an SI₂ diamond may look exactly the same, but these diamonds are quite different in terms of overall quality. This is why expert and accurate assessment of diamond clarity is extremely important.

A Diamond's Cut Unleashes Its Light

Diamonds are renowned for their ability to transmit light and sparkle so intensely. We often think of a diamond's cut as shape (round, heart/oval/marquise, pear), but a diamond's cut grade is really about how well a diamond's facets interact with light.

Precise artistry and workmanship are required to fashion a stone so its proportions, symmetry, and polish deliver the magnificent return of light only possible in a diamond.

To determine the cut grade of the standard round brilliant diamond - the shape that dominates the majority of diamond jewelry – GIA calculates the proportions of those facets that influence the diamond's face-up appearance. These proportions allow GIA to evaluate how successfully a diamond interacts with light to create desirable visual effects such as:

Brightness: Internal and external white light reflected from a diamond

Fire: The scattering of white light into all the colors of the rainbow

Scintillation: The amount of sparkle a diamond produces, and the pattern of light and dark areas caused by reflections within the diamond

GIA's diamond cut grade also takes into account the design and craftsmanship of the diamond, including its weight relative to its diameter, its girdle thickness (which affects its durability), the symmetry of its facet arrangement, and the quality of polish on those facets.

The GIA Diamond Cut Scale for standard round brilliant diamonds in the D-to-Z diamond color range contains 5 grades ranging from Excellent to Poor.

Diamond Carat Weight

Diamond carat weight is the measurement of how much a diamond weighs. A metric "carat" is defined as 200 milligrams.

Each carat can be subdivided into 100 'points.' This allows very precise measurements to the hundredth decimal place. A jeweler may describe the weight of a diamond below one carat by its 'points' alone.

All else being equal, diamond price increases with diamond carat weight, because larger diamonds are more rare and more desirable. But two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond 4Cs: Clarity, Color, and Cut.

It's important to remember that a diamond's value is determined using all of the 4Cs, not just carat weight.