4 Cs of Diamonds

Carat, Color, Clarity, and Cut. These basic factors will allow you to understand diamonds.

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Diamond ring

GIA created the first and most widely accepted standard for describing diamonds: Carat, Color, Clarity, and Cut. These basic factors will allow you to understand the value and price of diamonds.

Cut of the Diamond

The Diamond's Cut Releases Its Light

The most important of all the 4Cs is diamond cut. The diamond grader assesses the skill of the cutter in creating the diamond. The more beautiful the diamond will appear to the eye, the more precise it is.

Diamonds are known for their extraordinary ability to transmit light and shine intensely. A diamond's cut is often referred to as its diamond shape (round, oval, marquise, or pear), but it refers to how well the diamond's facets interact and reflect light. It takes precision and craftsmanship to create a stone that can return light in an extraordinary way which are generally used on a diamond engagement ring and other high value jewelry.

The diamond cut is critical to its absolute beauty and value. Unfortunately, it is also the most challenging and complex of all 4Cs.

The cut grade of a standard round brilliant diamond - which is the most popular shape in diamond jewelry – can be determined by GIA. This calculation calculates the proportions and appearance of the facets that affect the diamond's face-up appearance. In addition, these proportions enable GIA to evaluate the diamond's ability to interact with light to create desired visual effects, such as:

  • Brightness: The internal and external white light reflected by a diamond is internal and external.
  • Fire: The scattering white light into all colors of the rainbow.
  • Scintillation: refers to the amount of sparkle a diamond emits and the pattern of light- and dark-colored areas created by reflections within the diamond.

Carat Weight of the Diamond

Diamond Carat Weight measures a diamond's size.

The measurement of the weight of a diamond is called its "carat weight." Two hundred milligrams is the metric equivalent of a "carat."

Each carat can be divided into 100 points. This allows for precise measurements down to the hundredth decimal point. A jeweler might use the 'points' to describe the carat weight of a below-one carat diamond. For example, a jeweler might refer to a 0.25-carat diamond as a "twenty-five" pointer. Diamond weights higher than one carat are expressed using carats or decimals. For example, a 1.08-carat stone would be described by the jeweler as "one point oh eight."

Diamond prices rise with the diamond carat weight. This is because larger diamonds are rarer and more sought-after. Two diamonds with equal carat weights can have different fees and values depending on the other four Cs of diamonds: Color, Clarity, and Cut.

It is important to remember that diamonds are valued using all 4Cs and not just their carat weight.

Color Grade of the Diamond 

There are many colors available for a diamond's quality. The range of colors is from colorless to light yellow or light brown. The rarest are colorless diamonds. Although natural colors such as blue, red, and pink are called "fancy," their color grading differs from colorless white diamonds.

Most gem-quality diamonds are graded based on their absence of color. Chemically pure and structurally flawless diamonds have no hue. This gives them a higher value. Using a controlled lighting system and specific viewing conditions, GIA's D to Z diamond color-grading system compares a stone with master stones of known color values to determine the degree of colorlessness. These subtle distinctions in diamond color can be challenging to see, but the diamond quality and price may significantly differ from one diamond to another.

Clarity of the Diamond

Diamond Clarity refers to the absence of inclusions and blemishes.

There are two types of characteristics in diamonds: inclusions and blemishes. Rare are diamonds that don't have inclusions or blemishes. However, many aspects can only be seen under magnification.

Natural diamonds are formed when carbon is exposed to extreme heat and pressure deep within the earth. This can lead to various internal and external characteristics known as 'inclusions,' as well as 'blemishes.'

The number, size, and nature of diamond clarity characteristics are essential. They also have an impact on the overall appearance of the stones. Although no diamond is perfect, it will be more valuable if closer to its natural state.

Six categories make up the GIA Diamond Clarity Scale. Some of these are split to give you a total of 11 grades.

  • Flawless (FL). No inclusions or blemishes under 10x magnification
  • Internally Flawless (IF). No inclusions visible below 10x magnification
  • Very, Very Small Included (VVS1 & VVS2) Inclusions that are so small it is difficult for skilled graders to see below 10x magnification.
  • Very Slightly Included (VS1 & VS2) Inclusions can be observed under 10x magnification but are classified as minor.
  • Slightly Included (SI1 & SI2) Inclusions can be seen under 10x magnification.
  • Included (I1, II2, and I3) Inclusions can be seen under 10x magnification, reducing transparency and brilliance.