Kim Quang Logo - Logo has lettering saying Kim Quang Jewelery, with an illustration of a diamond on top.

4Cs of Diamonds
Defining a Gem’s Perfection

Tweezer with a round diamond stone on top of it place in a dark background

In the world of precious gems, nothing captivates quite like a diamond. 

If you’ve ever caught yourself entranced by the sparkle of that magical gem but felt somewhat bewildered by what lies behind its brilliance, know you’re not alone. 

In the past, diamonds were described with enigmatic beauty using terms such as “river” for the most pristine gems, and “Cape” for the sun-kissed yellows from South Africa’s renowned region. And when describing the diamond’s cut, vague terms such as “made well” or “made poorly” were used. They were exciting times, but these terms used to describe diamond quality certainly lacked precision! 

Then in the 1940s, Robert M. Shipley introduced a universally utilized system, coining the term “4 C’s” to help his students remember the four factors of a quality diamond: color, clarity, cut, and carat weight. These small words altered the way we interact with diamonds forever.

Today we’re going to decode these 4 C’s, breaking down the beauty of diamonds and shedding light on the characteristics that shape a diamond’s splendor. 

We’ll look at:

  • Color: What does it mean and how does it affect a diamond’s beauty?
  • Clarity: What’s hiding inside a diamond and why does it matter?
  • Cut: How do the shape and crafting of a diamond play into its allure?
  • Carat Weight: What’s in a size, and why does the weight matter?
 We will also discuss which of these is the most important.

A Look at Diamonds: Breaking Down the 4 C’s

The 4 C’s are vital characteristics that can transform a mere rock into a breathtaking gemstone. They are the alchemy that breathes life into an otherwise ordinary mineral, awakening its inner fire and brilliance.

Let’s look at each one in more detail.

Color: What It Means & How it Affects A Diamond’s Beauty

When it comes to diamonds, color functions as a paradox, a unique attribute that is often gauged by its absence. The less color you see, the more valuable the diamond. 

A truly colorless diamond is very rare, a marvel of nature’s perfection and a zenith of purity. 

Diamond color chart on a white background
Fig 1. The GIA diamond color scale

As you move down the scale, from D to Z, the colors appear. Often whispers of yellow or brown. These colors reveal where the shadows of the earth’s depths are and where the diamond was born. 

The perception of color in a diamond also depends on the cut and how it interacts with light. 

The light can enhance or mask a diamond’s color, influencing how the hue is experienced. Because this interaction is so sensitive, even a slight change in lighting can make a noticeable difference in the diamond’s appearance and value


Clarity: What’s Hiding Inside & Why It Matters

Clarity is a measure of a diamond’s internal and external imperfections, known as inclusions and blemishes. 

The GIA International Diamond Grading System assigns a clarity grade that ranges from flawless (FL) to diamonds that have inclusions that are quite obvious (I3). 

Diamond clarity chart
Fig 2. The GIA diamond clarity scale
Diamond clarity chart on a white background
Fig 2. The GIA diamond clarity scale

The GIA clarity grading system has six main categories and each one is further subdivided. 

  1. Flawless (FL): Flawless diamonds are ones that are untouched by time or turmoil and have no inclusions or blemishes detectable under 10x magnification.

  2. Internally Flawless (IF): An internally flawless diamond doesn’t have any inclusion and only very minor or insignificant blemishes.

  3. Very, Very Slightly Included (VVS1 and VVS2): When a diamond has a VVS1 or VV2 grading it means the inclusions are very slight, usually even skilled graders will struggle to locate them.

  4. Very Slightly Included (VS1 and VS2): A slightly included diamond has detectable inclusions.

  5. Slightly Included (SI1 and SI2): Inclusions are noticeable.

  6. Included (I1, I2, and I3): When a diamond is included, it features both inclusions and blemishes. 
Clarity matters because it affects how light dances within a diamond, and how it influences its sparkle and fire. The fewer inclusions and blemishes, the more brilliant the diamond, and the more valuable. 

Cut: The Shape, Craftsmanship, and Brilliance

The diamond’s cut is judged by how the diamond handles light, and here we have three factors that come into play: 

Fire: The dispersion of light into the colors of the spectrum 
Brilliance: The total reflection of white light 
Scintillation: The flashes of light, or sparkle that are visible when the diamond moves. 

Diamond cut chart guide
Fig 3. Diamond cuts and their light effects. From left: "Ideal" cut with optimal light return, "Too Shallow" cut losing light at the bottom, and "Too Deep" cut where light escapes the sides. Cut quality directly impacts brilliance and fire.

The diamond’s cut is judged by how the diamond handles light, and here we have three factors that come into play: 

  1. Fire: The dispersion of light into the colors of the spectrum 
  2. Brilliance: The total reflection of white light 
  3. Scintillation: The flashes of light, or sparkle that are visible when the diamond moves. 

Essentially speaking, a diamond’s cut is about how well a diamond is designed and crafted to reflect light. But it goes deeper than that. We also have proportions, symmetry, and polish. 

  • Proportions: This refers to a diamond’s dimensions and angles, and their harmony is what ensures that the light entering the diamond is properly reflected to create optimal fire, brilliance and scintillation.
  • Symmetry: Symmetry is about the alignment of the diamond’s facets and is all about balance, grace, and elegance. Many things impact a diamond’s symmetry, such as the facets, crown angles, etc.
  • Polish: Polish is all about the smoothness of the diamond’s surface and facets and it’s what causes a more dazzling appearance. An excellent polish makes sure that light is not scattered or absorbed at the surface. 

Cut has a GIA grading system that ranges from Excellent, Very Good, Good to Fair, and Poor. 


Carat Weight: Why Size & Weight Matter

Diamond carat weight is the actual weight of the diamond, measured in carats, and plays a vital role in the value of a diamond. 

To understand the carat weight, you need to understand that diamonds are often measured in points, with 100 points equating to one carat, and one carat is equal to 0.2 grams. 

The price of a diamond increases with diamond carat weight because bigger diamonds are rare, making them more precious and expensive. 

Diamond grading chart shows different carat weights on a white background
Fig 5. Approximation of round diamond sizes according to their carats.
Fig 5. Approximation of round diamond sizes according to their carats.

There are other things that play a role in the final value of a diamond though.

Carat weight alone doesn’t always dictate the final value of a diamond. This is because of how weight is distributed and how it interacts with the other factors such as cut, color, and clarity, which are all equally important. 

Also, the weight doesn’t always translate directly to how large diamonds appear, as a well-cut diamond can make the most of its carat weight and look larger to the eye. 

Diamond shapes also play a role. They can either emphasize or disguise the carat weight, and some shapes can make the diamond appear bigger or smaller than the actual carat weight.

Taking all this into account, carat weight is far from a solitary measure!

Now that we’ve covered the 4 C’s, you’re probably wondering which of them is the most important. 


What’s The Most Important C & How Do You Choose Diamonds Based On The 4Cs?

While each of the 4 C’s – color, clarity, cut, and carat weight – plays a vital role in determining a diamond’s value and allure, many gemologists and aficionados consider the cut to be paramount. The reason is simple: the cut determines how the diamond interacts with light, how it sparkles, and, ultimately, its overall brilliance.

A diamond’s cut isn’t just about its shape, but how well its facets interact with light. This involves precise artistry and workmanship to ensure the diamond reflects light brilliantly. A well-cut diamond can make colors appear more vibrant and hide imperfections from the naked eye. On the contrary, even a diamond of the highest quality, in terms of clarity and color, can appear lifeless if its cut is subpar.

However, choosing the perfect diamond goes beyond just its technical attributes. It’s more than just a checklist or a chart. Personal preference plays a major role. Some might prioritize size while others might lean towards a particular shape or color. Preference, aesthetics, budget, and choosing a stone that feels right are all important points to consider. 

At Kim Quang Jewelry, your story is waiting to be discovered, celebrated, and cherished forever. If you’re looking for a diamond that doesn’t just catch your eye, but one that will capture the essence of your love, our GIA gemologist will gladly help you find the perfect stone.