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What Are The Characteristics Of A Diamond?

What Are The Characteristics Of A Diamond?

We all love diamonds. There is something really special about them, and we are here to talk about it.

What is it that makes them so shiny, so satisfying to look at? What are the characteristics of a diamond? Those special features that make them so special? Find out more about it in the article below.

We all know that diamonds are minerals with crystal structures, formed when the carbon molecules. They form when the carbon is exposed to extreme heat and pressure inside the Earth’s mantle, more than 100 miles deep below the surface.

Now that is just the beginning of the journey for that gem, after being mined from the Earth, each and every diamond is carefully examined and processed in order to be presented as a part of an earring, ring, necklace, or maybe sold individually.

That process is what gives the diamonds those characteristics they are famous for, the 4 C’s – Carat, Color, Clarity, and Cut.

Let’s dive in and explore what that means, and how to understand these amazing gems!

Origins Of The 4C Quality System

People know about diamonds and their value for a long time. And it was not an easy task for them to process or even measure diamonds before modern science existed.

The system we have in place today, the 4C’s was mentioned for the first time in the early 1940s as an idea created by Robert M. Shipley, founder of the Gemological Institute Of America.

He established GIA in order to provide formal training for the jewelers and wanted to create a network of knowledgeable people with ethical and scientific standards in the gem markets.

He came up with the 4C method in order to help his students remember the most important characteristics of a faceted diamond which are: carat, color, clarity, and cut.

That system was later popularized through advertising campaigns, lectures, and courses, within decades it was the best grading system, integrated into the international nomenclature.

Next president of the GIA, Richard T. Liddicoat, along with many of his colleagues expanded and perfected the 4C system.

They developed the “GIA D-to-Z Color Scale” and “GIA Clarity Scale” for diamonds, and also procured countless scientific methods and procedures used for objective grading of diamond’s quality.

Systems in place are developing even today, and with modern technology used in scientific research, we get more precise measures and systems that are used by all prominent jewelers around the globe.

We hope that we piqued your interest in this topic, so let’s dive in and explain What are the characteristics of a diamond?


Carat is a measurement unit, used to define the weight of a diamond. Because diamonds are very valuable, and they often can be very small, people realized that conventional weight units are not precise enough to measure diamonds.

As far back as a couple of centuries ago, people started using carats to measure a diamond’s weight.

One carat is equivalent to 0.2 grams, or 0.007 ounces.

Even further, we split each carat into 100 equal points. That is important, although every point counts when calculating a price for a specific diamond, whole carat diamonds are regarded as the best.

For instance, if you buy a 0.99 carats diamond, you will find a sizable decrease in value compared to a 1-carat diamond.

Another thing to keep in mind is that carats only refer to diamond weight, and not the size itself.

Normally, a 1-carat diamond is 6.5 millimeters in diameter. That is considered to be an ideal size. But not all things are perfect, and you can often find 1-carat diamonds that are smaller and are valued less.

You should be aware that bigger, heavier diamonds, of gem quality, are very rare, and that makes them exponentially increase in price.

For example, a 1-carat diamond is worth 4 times more than a 0.5-carat one.

Also, you should be aware that bigger diamonds are more expensive than smaller ones. That means if you choose between several diamonds that are all measured as 1-carat, the largest will be the most expensive one.

Bottom line is that carat weight directly affects the price. Heavier is more valuable when talking about diamonds.


A widespread myth is that diamonds are colorless. On the contrary, most of them have a subtle color. The color of a diamond greatly influences its beauty and price. In this case, less color means better quality.

The most widely accepted color scale today is the GIA Color Scale, and it’s used by most prominent jewelers. This scale orders the color of diamonds in alphabetical order, from the letter D (perfect colorless) to Z (yellow or brown)

Letters D, E, and F represent colorless diamonds, G, H, I, and J near colorless ones, K, L, and M are faint yellow, N, O, P, Q, and R represent the very light color, and letters S to Z are reserved for the light colored pieces.

Color evaluation of a diamond is conducted in strictly controlled conditions by comparing the diamond to round brilliant diamonds of known color, called the master stones.

The most important elements of diamonds’ color are tone and saturation.

Some rare diamonds are found to have a variety of strong colors, and those are called “Fancy Color Diamonds” or “Fancy Stones”. They come in almost all colors imaginable.

Yellow and brown diamonds are the most common of all, and they are considered less valuable, but there are also pink and blue diamonds, and the rarest are red, orange, purple, and green.

A well-known example of a fancy diamond is the Orloff diamond, named after the Russian princess, it is a 67.50 carats black diamond.


Next on the list of important characteristics is diamond clarity, often called diamond purity.

Diamonds spend thousands of years in the heat and pressure deep inside the Earth, and that process leaves inclusions in diamonds that determine their clarity.

The degree of purity of a diamond is determined according to the number, size, and position of its external marks and inclusions.

Using a 10x magnification glass, jewelers observe the diamond and compare it to the most used purity scale, made in the GIA gemological laboratory.

The scale is divided into 11 grades, ranging from the highest degree of purity, FL (flawless) to grade I (Inclusions visible), also called Pique.

The categories of the scale are:

  • F and IF for completely pure diamonds
  • VVS1 and VVS2, meaning “Very, Very Slightly Included” for diamonds with almost negligible imperfections
  • VS1 and VS2, meaning “Very Slightly Included”
  • SI1 and SI2, meaning “Slightly Included”
  • I1, I2, and I3, for diamonds that have “Inclusions Visible to the naked eye”, also called pitted, or pique.

Using these categories, jewelers usually discard “the minced diamonds” that belong to categories I1, I2, and I3.

The clarity of a diamond is directly correlated to its price. The purer diamond is always more valuable.

It is advisable to pick a diamond from a VS1 or VS2 grade because they possess inclusions that are so slight that they are invisible to the naked eye.


The cut of a diamond refers to the precision of angles, proportions, symmetry, and polish that are the result of the careful processing done by a jeweler.

The cut will directly impact the fire and scintillation of a diamond. The important thing is not to confuse the diamond cut with the stone’s shape, which can be oval, round, pear, cushion, etc., and the facet arrangement, which can be steep or brilliant.

Once again, we refer to the GIA, which made the most used scale for grading the cut of a diamond. They grade round brilliant diamonds on a five-point scale, Excellent, Very Good, Good, Fair, and Poor.

The Excellent cut grade means that the diamond provides maximum fire, brilliance, and scintillation.

There is another grading system, that is based on 7 factors:

  1. Brightness – How bright the stone is when viewed face-up
  2. Fire – Refraction of light that goes through the diamond
  3. Scintillation – Blinking flashes of light from facet to facet towards the center of a diamond when you move the stone
  4. Weight ratio – The relation between the weight and the size of a diamond
  5. Durability – The ability of the stone to withstand wear, heat, and chemical exposure
  6. Polish – The degree of smoothness of each facet of a diamond
  7. Symmetry – Precision of the various facets of a diamond, their alignment, and intersection

Diamond cut quality is considered the most important indicator of a diamond’s beauty and should be made a priority over other characteristics.

The quality of craftsmanship can make an average diamond extremely beautiful, but if done incorrectly it can decrease the value of the gem.

You should note that, unlike regular diamonds, fancy-color diamonds are not cut to maximize their brilliance. These diamonds are cut to achieve the best color possible.

That means that proportions that are considered ideal for regular diamonds do not apply to fancy-colored ones.

When buying a fancy diamond, you should focus on its color intensity and hues, instead of judging the gem by traditional cut grades.


Although not a part of the well-known 4C grading system, fluorescence is a characteristic of a diamond that can greatly influence its price and beauty.

Fluorescence represents the tendency of a diamond to emit a soft glow when exposed to ultraviolet light. It is present in approximately 30% of the diamonds in the market.

It is caused by the incorporation of natural elements, such as boron, nitrogen, or aluminum during the formation process of diamonds.

The electrons present in those elements absorb the energy from UV light, which can cause them to glow with faint light.

Usually, fluorescence is blue in color, but less often diamonds can have a yellow or even white glow. Gems with strong or very strong fluorescence can appear to be cloudy or hazy to the naked eye.

Naturally, there is a scale built to determine a diamond’s fluorescence grade, based on its intensity. The scale provided by the GIA, grades diamonds fluorescence from best to worse, in this order:

  • None – Diamonds with no fluorescence present will receive a grade of None
  • Faint – Very slight amount, not detectable by the naked eye
  • Medium – Stronger blue glow under UV light, usually not detectable to the naked eye.
  • Strong – Substantial and intense blue hue under UV light, can cause the diamond to be very hazy or cloudy even when observed with the naked eye.
  • Very Strong – Exhibit a prominent and saturated blue hue when exposed to UV light, chances are it will look very cloudy when observed in normal light.

Any presence of fluorescence will negatively impact its price. Greater the grade, the more damage it can do to the value of the gem.

Diamond sellers usually discard diamonds that have more than 40% of fluorescence.

The thing to keep in mind is that lower color ranges of diamonds are not as greatly impacted by fluorescence as are their fancy-colored counterparts.

In Conclusion

Now that we know the answer to the question, “What are the characteristics of a diamond?”, what do you think about all of them? What do you believe is the most important characteristic of a diamond?

If you would like to take a peek at our list of the most important diamond characteristics, maybe it would be a good idea to take a look at this article: 4 C’s Of Diamonds – Order Of Importance: The Most Important C?

Some of them are certainly more important than others, given that they have more influence over the value of the stone.

Knowing what 4C’s method is, and how it is used, we hope that we made it easier for you to find the perfect diamond that suits your needs!