Beautiful. Rare. Cherished. Each diamond is unique and is a miracle of time, place and change. And each has specific qualities that establish its value.
Until the middle of the twentieth century, there was no agreed-upon standard by which diamonds could be judged. GIA created the first, and now globally accepted standard for describing diamonds: Color, Clarity, Cut and Carat Weight. Today, the 4Cs of Diamond Quality is the universal method for assessing the quality of any diamond, anywhere in the world. The creation of the Diamond 4Cs meant two very important things: diamond quality could be communicated in a universal language, and diamond customers could now know exactly what they were about to purchase.
Understanding what diamond color means helps in choosing the right diamond. Interestingly, the diamond color evaluation of most gem-quality diamonds is based on the absence of color. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. GIA’s D-to-Z diamond color-grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to masterstones of established color value.
Many of these diamond color distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price. Hence, it is important to get a GIA expert’s opinion in evaluating the best color for your diamond.
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.
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
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 – GIA calculates the proportions of those facets that influence the diamond’s face-up appearance. These proportions allow GIA 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
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.
4Cs of diamond quality will help you learn how to buy a diamond. This basic knowledge will not only unlock the mystery of a diamond’s quality, it will also help you understand a diamond’s value and price.
- Diamond Color In most diamonds, the term actually refers to the absence of color. The less color in the stone, the more desirable and valuable it is. Some of these differences are not visible to the naked eye, but directly impact the overall quality and price of the stone.
- Diamond Clarity measures the amount, size and placement of internal ‘inclusions,’ and external ‘blemishes.’ Grades run from ‘Flawless,’ with virtually no imperfections, to ‘Included,’ which contain a significant number of imperfections.
- Diamond Cut does not refer to a diamond’s shape, but to the proportion and arrangement of its facets and the quality of workmanship. The amount of brilliance, sparkle and fire in a diamond is determined by cut. Grades range from ‘Excellent’ to ‘Poor.’
- Diamond Carat refers to a diamond’s weight. Generally speaking, the higher the carat weight, the more expensive the stone. Two diamonds of equal carat weight, however, can have very different quality and price when the other three Cs are considered.
No matter how beautiful a diamond may look you simply cannot see its true quality. Knowing more about the 4Cs of diamond quality will help you learn how to buy a diamond. The 4Cs provide you with the information you need to know the diamond’s actual quality.
Your jeweler should be armed with expert training, open to questions and able to explain how to buy a diamond in clear, simple language. A jeweler’s professional training can help you evaluate how knowledgeable he or she is. Preferably, their training comes from a highly recognized and internationally accredited program, such as the GIA Graduate Gemologist (GG) or Applied Jewelry Professional (AJP) diploma programs. As your personal diamond-buying guide, an educated jeweler will not only explain the 4Cs of Diamond Quality to you, but will also be able to demonstrate the differences between apparently similar stones. They will encourage you to compare a number of diamonds that fall in your budget.
A diamond grading report from an unbiased, scientific source such as GIA is more than important information, it’s proof of what you are buying. The differences in diamonds can be so subtle, even a trained jeweler can’t recognize them without lab verification. Insist that any diamond you buy come with an indisputable verification of its quality.
Once you’ve purchased the right diamond, have it appraised and insured. Appraisers and insurers rely on diamond grading reports to accurately evaluate the value of gems. As an additional measure, consider having your diamond laser-inscribed with its GIA report number, to provide verification if it is ever lost or stolen.
What is a GIA Graduate Gemologist (GG)?
The prestigious GIA Graduate Gemologist diploma program teaches jewelers the science and technical knowledge needed to deal with the entire spectrum of diamonds and colored stones. The distinguished GIA GG designation at the end of an individual’s name is instantly recognized around the world as the mark of a senior professional in the jewelry industry.
What is an Applied Jewelry Professional (AJP)?
The GIA Applied Jewelry Professional credential is a professional development program designed specifically for sales associates and provides them the essential product knowledge to communicate the right information on how to buy a diamond to their customers.
Diamond Origin Report is a full assessment of a diamond’s 4Cs of Diamond Quality (Color, Clarity, Cut and Carat Weight) and uses scientific matching to determine a diamond’s geographic origin. Every GIA Diamond Origin Report and GIA Colored Diamond Origin Report includes:
- A printed report containing GIA’s full, unbiased and authoritative 4Cs grading assessment, including a plotted diagram of your polished diamond
- Confirmation of your diamond’s geographic origin, with the country clearly stated on the report
- Inscription of the report number on your diamond’s girdle for added security and identification
- Full-color digital images of your diamond in its rough and polished state and an image-rich story of the diamond’s country of origin and transformational journey available on the GIA Origin App and Report Check
