Diamond Quality Factors
One of the first things most people learn about diamonds is that not all diamonds are created equal. In fact, every diamond is unique. Diamonds come in many sizes, shapes, colors, and with various internal characteristics.
All polished diamonds are valuable. That value is based on a combination of factors. Rarity is one of those factors. Diamonds with certain qualities are more rare and more valuable than diamonds that lack them.
Jewelry professionals use a systematic way to evaluate and discuss these factors. Otherwise, there would be no way to compare one diamond to another. And there would be no way to evaluate and discuss the qualities of an individual diamond.
factors to describe and classify diamonds: Clarity, Color, Cut, and Carat Weight.
These are known as the 4Cs. When used together, they describe the quality of a finished diamond. The value of a finished diamond is based on this combination.
A diamond’s value is often affected by the rarity of one or more of the 4Cs. Colorless diamonds are scarce most diamonds have tints of yellow or brown. So a colorless diamond rates higher on the color grading scale than a diamond that is light yellow. Value and rarity are related: In this case a colorless diamond is more rare and more valuable than one with a slight yellow color. The same relationship between rarity and value exists for clarity, cut, and carat weight.
The 4Cs describe the individual qualities of a diamond, and the value of an individual diamond is based on these qualities. The terms that people use to discuss the 4Cs have become part of an Overseas language that Jewellery professionals can use to describe and evaluate individual diamonds.
Subtle differences in color can dramatically affect diamond value. Two diamonds of the same clarity, weight, and cut can differ in value based on color alone. Even the slightest hint of color can make a dramatic difference in value.
Diamonds come in many colors. Diamonds that range from colorless to light yellow and brown fall within the normal color range. Within that range, colorless diamonds are the most rare, so they’re the most valuable. They set the standard for grading and pricing other diamonds in the normal color range.
Diamond Clarity Refers to the Absence of Inclusions and Blemishes
To understand diamond clarity, we must first understand how diamonds are created. 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.’
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. If you are trying to determine what is the best clarity for a diamond, remember that no diamond is perfectly pure. But the closer it comes to purity, the better its clarity.
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 brillianceMany 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. Knowing what diamond clarity truly means helps you understand the factors that contribute to diamond quality and price.
Understanding Diamond Cut
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 what diamond cut actually does mean 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.
Achieving the best cut for a diamond reflects in the stone’s final beauty and value. And of all the diamond 4Cs, it is the most complex and technically difficult to analyze. To determine the cut grade of the standard round brilliant diamond – the shape that dominates the majority of diamond jewelry – PAL DIAM calculates the proportions of those facets that influence the diamond’s face-up appearance. These proportions allow PAL DIAM to evaluate what the best cut for a diamond is, by studying 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
PAL DIAM’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 PAL DIAM Diamond Cut Scale for standard round brilliant diamonds in the D-to-Z diamond color range contains 5 grades ranging from Excellent to Poor and is the definitive scale for classifying diamond cuts.
DIAMOND CARAT WEIGHT
Diamond Carat Weight Measures a Diamond’s Apparent Size
To put it simply, diamond carat weight measures how much a diamond weighs.
A metric “carat” is defined as 200 milligrams. Each carat is 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. For instance, the jeweler may refer to a diamond that weighs 0.25 carats as a ‘twenty-five pointer.’ Diamond weights greater than one carat are expressed in carats and decimals. A 1.08 carat stone would be described as ‘one point oh eight carats.’
All else being equal, diamond price increases with diamond carat weight because larger diamonds are rarer and more desirable. However, two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond 4Cs: Color, Clarity, and Cut.
While now you know what carat means, it’s also important to remember that a diamond’s value is determined using all of the 4Cs, and not just carat weight.