A Guide to the 4Cs of Your Diamond Engagement Ring

Choosing the best diamond for your engagement ring can be hard. “How big should it be?” “What is a good quality diamond?” “How much will it cost me?” are just some of the questions we ask as we look at our options.

We want to lighten the load for you. In this article, we discuss the “4 C’s” to look for when judging a diamond, which is the most important, and what to do once you’ve found your perfect stone.

What are the 4 C’s for?

Diamonds are forever, and history shows it with how well-loved they’ve been for centuries. But in the past, there was no one way to describe a diamond. Jewelers used vague phrases like it was “made well” or “without flaws.” As such, it was difficult for both professionals and customers to have one clear understanding about the stone.

That is until the Gemological Institute of America (GIA) created the “4 C’s” of a diamond – cut, color, clarity, and carat. This tells us the quality of a diamond using a strict set of standards. Since the 1940s, it has been universally embraced across cultures, customers, and jewelers alike.

Diamond Quality Chart, in order of importance when deciding



The cut tells you the specific proportions and angles of your diamond, and how this interacts with light. Your diamond will have high levels of fire and brilliance when skillfully cut. This “wow factor” makes the light shining on the stone bounce back to your eye beautifully and brightly. 

The GIA assesses cut grades with a scale of Excellent, Very Good, Good, Fair, and Poor. There are also levels to each grade. For example, a diamond may be graded “3 EX” or triple excellent; meaning, it is excellent in cut, polish, and symmetry. 

On the other hand, the International Gemological Institute (IGI)’s, another laboratory that grades diamonds, has “ideal” for the highest cut grade.

Below, we see what a poor GIA cut grade looks like versus an excellent cut grade:

The GIA also provides a booklet for their cut grades here.

Note: Only round cuts receive a cut grade, as other fancy shapes like ovals or princess cuts have too many shape variations to have a standardized grade.

Key takeaway: The cut of a diamond is the most important,  as it determines the stone’s sparkle through levels of fire and brilliance.


Second is the clarity. Because diamonds are formed under extreme heat and pressure, they may have inclusions and blemishes. Inclusions are characteristics within a diamond, and blemishes are characteristics on the surface. Clarity tells you the nature and number of inclusions and blemishes.

The IGI and GIA grades clarity through the following levels:

Visual chart from the IGI
The amount of inclusions and blemishes can obstruct the light that passes through your diamond, making it duller and less sparkly. Bigger carat diamond rings benefit from higher clarity, but it is enough for the stone to look “eye clean.” Meaning, it is free from inclusions and blemishes to the naked eye.

An engagement ring with a VVS1 clarity grade

At Brilyo Jewelry, we take careful steps to curate the cleanest diamonds for you. We usually offer VS2 and above to guarantee that your diamonds look eye clean.

Key takeaway: Clarity tells you how many inclusions and blemishes a diamond has. A lower clarity may hinder the sparkle, so it is best to choose clarity grades higher than SI when buying a diamond ring.


Color tells you how white or colorless a diamond is. The GIA scale ranges from D to Z, with D being the most colorless, and Z being the most yellow (not to be confused with a yellow diamond). Diamonds that are more colorless tend to be more valuable and expensive, as they are rarer than yellowish ones.

Real diamond color examples from the International Gem Society

When choosing the color of your diamond, you should think of your preferred shape. For example, it is popular for an emerald cut diamond to be colorless or near colorless, as they tend to show more color. 

Meanwhile, a round brilliant cut may still look colorless in H to I color grades as they are great in hiding yellow tint.


 Top to bottom: Two H color grades with one D color grade

At Brilyo Jewelry, we make sure to have the most high quality color options available for your picking.

Key takeaway: Diamond colors range from D to Z or colorless to light yellow. G-J are the best value for money, but personal preference is the most important.


Last in the 4 C’s, a carat simply refers to the diamond’s weight, with one carat equalling to ⅕ of a gram. Meanwhile, smaller diamonds can be measured in “millimeters,” with one point equaling to 0.01 carat. Gemologist Renee Newman summarizes carat sizes to point equivalents:



Point equivalent


Half point (0.5 pt)


Five points


25 points or quarter carat


Fifty points or half carat

From Renee Newman’s Book, “Diamond Ring Buying Guide

Some people believe that the higher the carat, the “better” the diamond. However, you should also think of the C’s mentioned above. A large carat diamond does not always mean it is brilliant and clear to the eye.


 Comparison of 1ct, 1.5ct, and 2ct

Key takeaway: Carat tells you the weight of a diamond. The bigger the carat, the heavier the diamond.

Making sense of the 4 C’s

The cut, for round brilliants, is the most important part to consider because the proportions and angles of your diamond directly impact its ability to sparkle brilliantly.

Second is clarity, as certain shapes may be more prone to showing inclusions than others. Choose a diamond that is eye clean. 

Afterwards, select the color of your diamond. As mentioned prior, diamonds that are more colorless tend to be rarer and more expensive. Certain shapes may also conceal yellow tint better than others. 

While D-F color grades are the most preferred choice, G-J grades are the best value for money as they still resemble colorlessness to the naked eye.

Lastly, select the carat size of your diamond. The careful steps you’ve undergone will help create an exquisite engagement ring regardless of carat size.

 A pair of GIA-certified diamond studs with the following specs:
3.08ct round G VVS2 3EX and 3.14ct H VVS2 3EX

Remember, these steps are not set in stone. Your personal preference is still the most important, along with your budget. You may prioritize carat size more than color or clarity grade, and that’s more than okay! 

Nevertheless, our team of Jewelry Experts is prepared to help you find the perfect balance of the 4 C’s when you purchase a diamond. Feel free to contact us or book a consultation.

“What do I do next?”

After looking at the 4 C’s, it’s best to check design inspirations or talk to professional jewelers. Ask about the cut, color, clarity, carat, and other details you want to know to get a deeper understanding of your piece.

Here at Brilyo Jewelry, we offer carefully selected, high quality diamonds that are GIA, IGI, or store-certified so you know the exact qualities of the diamond you are purchasing. 

Lastly, choose a jeweler that displays expertise in their craft. Poorly made rings can hinder the sparkle and beauty of your diamond, meaning, the craftsmanship is just as important as the diamond itself.



A Brilyo-made ring with an underside pave, with gemstones as small as 1 mm.

This is why we’re careful to craft each jewelry piece pre-ordered from us. With our skilled Australia-based jewelers, we are able to craft timeless rings with expert precision and quality. We want to ensure that your ring is a worthy testament of your love. 

Begin crafting your engagement ring today! View our wide selection of diamond engagement rings today, or custom create your own. Together, let’s create a jewelry piece that will last a lifetime and more.