Diamonds are graded based on four quality factors, commonly known as the diamond 4cs chart. Understanding these criteria will help you make an informed purchase.
The 4Cs include cut, color, clarity and carat weight. Together, they form a grading scale that helps diamond sellers determine the value and compare diamonds.
Color
Color is one of the most important factors in determining diamond quality and its price. The Gemological Institute of America (GIA) grades a diamond’s color, from D to Z.
The GIA’s color scale begins with completely colorless diamonds, and moves down the alphabet to include diamonds that have a faint tint. While these colors are not as desirable as colorless diamonds, many buyers prefer them for their warmth and value.
Another factor in determining diamond color is the color of the metal used to mount the stone. For example, a white gold setting will appear more colorless than a yellow-gold ring.
The best way to determine a diamond’s color is to look at it from several angles and compare it to a diamond color chart. Then, you can understand which grade of color is ideal for your budget and style preferences.
Clarity
Clarity is one of the four characteristics of a diamond that affects its beauty and value. It grades how clean a diamond is from internal and external imperfections called inclusions and blemishes.
As diamonds form deep within the earth, they can develop small fractures or slight traces of minerals that can impact the way light refracts and reflects. This is what makes natural diamonds unique and gives them their personality.
These tiny markings are what make diamond clarity so important. GIA has developed a diamond clarity grading system to help the consumer understand what makes one diamond worth more than another.
The clarity of a diamond is assessed by a trained grader using 10x magnification. The assessment takes into account the size, location, nature, number and color of inclusions or blemishes.
Cut
As you probably know, a diamond’s value is determined by the Diamond 4Cs (color, clarity, cut and carat weight)—the terms for which are often referred to as “The 4Cs” or “The Big Four.”
The most important of the 4Cs is cut. The cut of a diamond determines how light reflects off the stone and makes it sparkle and shine.
A properly-cut diamond is also a lot more durable than an inferiorly-cut diamond. In addition, a well-cut diamond will look larger and improve its face-up color and help mask inclusions.
The cut grade of a diamond is given by the Gemological Institute of America (GIA) on a scale of Excellent to Very Good, with a higher score indicating a better-cut diamond. This is why it’s important to see a diamond up close and examine it thoroughly.
Carat Weight
Carat weight is one of the four main quality factors that jewelers use to determine the value of a diamond (also known as the 4Cs). Larger diamonds are rarer and more desirable.
This means that two diamonds of the same carat weight can have very different values and prices, depending on the other three components of a diamond’s quality: Color, Clarity and Cut.
To keep it accurate, GIA and other labs weigh diamonds using sensitive electronic micro-balance scales. They measure the weight to the fifth decimal place, or a hundred thousandths of a carat, for maximum precision.
In the trade, however, a diamond’s carat weight is usually stated to two decimal places, or a hundredth of a carat. GIA rounds off its weights using stricter rules than mathematical rounding, so the last digit in a thousandths place is always a 9.
