The 4Cs of Diamonds
Understanding Cut, Colour, Clarity & Carat
Choosing a diamond can feel overwhelming. With so many different sizes, shapes and prices, it can be difficult to know what actually makes one diamond different from another.
The 4Cs — Cut, Colour, Clarity and Carat — are the four characteristics used to describe and evaluate a diamond.
Understanding the 4Cs can help you make a confident decision and find a diamond that looks beautiful while staying within your budget.
Cut
How Well Does the Diamond Reflect Light?
Cut refers to how well a diamond has been proportioned, polished and finished to interact with light.
Cut is especially important because it has a major effect on a diamond's brightness, sparkle and overall appearance.
A well-cut diamond can reflect light beautifully, creating the bright flashes and sparkle that make diamonds so captivating.
Why Does Cut Matter?
A diamond with excellent proportions can appear more lively and brilliant than a poorly cut diamond of the same carat weight.
When choosing a diamond, cut is one of the characteristics we recommend paying close attention to.
Cut Grades
For round brilliant diamonds, cut grades commonly range from:
Excellent
Exceptional light performance and sparkle.
Very Good
Strong light performance with excellent overall appearance.
Good
Adequate light performance, often at a lower price.
Fair / Poor
Less efficient light reflection and generally less sparkle.
Cut grading systems can vary depending on the diamond shape and grading laboratory.
Colour
How Colourless Is the Diamond?
Colour refers to how much body colour can be seen in a diamond.
For the traditional D-to-Z colour scale, diamonds are graded from:
D — Completely Colourless
through to
Z — Noticeable Warm Colour
Generally, the higher the diamond is on the colour scale, the more colourless it appears.
Why Does Colour Matter?
Colour can have a noticeable effect on how a diamond looks, but the ideal colour depends on the diamond's shape, setting and your personal preference.
Some diamond shapes show colour more readily than others.
For example, elongated shapes such as oval, pear and emerald-cut diamonds can sometimes show more warmth than round diamonds of the same colour grade.
Do You Need a D Colour Diamond?
A diamond doesn't have to be D colour to look beautiful.
For many jewellery designs, a G, H or I colour diamond can provide an excellent balance between appearance and value.
The colour of the setting can also influence how the diamond appears.
Clarity
How Many Natural Inclusions Does the Diamond Have?
Clarity refers to the presence of internal characteristics, called inclusions, and surface characteristics, called blemishes.
Most natural diamonds contain tiny characteristics that formed as the diamond developed underground.
These characteristics are what gemologists examine when determining a diamond's clarity grade.
Clarity Grades
The commonly used clarity scale includes:
FL — Flawless
No inclusions or blemishes visible to a skilled grader under 10× magnification.
IF — Internally Flawless
No visible inclusions under 10× magnification.
VVS1 / VVS2 — Very, Very Slightly Included
Very difficult to see inclusions under 10× magnification.
VS1 / VS2 — Very Slightly Included
Minor inclusions that can be difficult to see under 10× magnification.
SI1 / SI2 — Slightly Included
Inclusions are more noticeable under magnification and may sometimes be visible to the naked eye.
I1 / I2 / I3 — Included
Inclusions are more apparent and may affect transparency and brilliance.
Does Higher Clarity Always Look Better?
If a diamond's inclusions cannot be seen with the naked eye, paying for a significantly higher clarity grade may not create a noticeable visual difference.
This is why we often recommend looking for a "eye-clean" diamond — one that appears clean to the naked eye while offering better value.
Carat
How Much Does the Diamond Weigh?
Carat refers to the weight of a diamond, not its physical size.
One carat is equal to 0.20 grams.
A diamond can also be described in points:
1.00 carat = 100 points
0.50 carat = 50 points
0.25 carat = 25 points
Does More Carat Mean a Bigger Diamond?
Two diamonds with the same carat weight can look noticeably different in size depending on their shape, proportions and how the weight is distributed.
For example, an elongated oval may appear larger from the top than a round diamond of the same carat weight.
This is why we recommend looking at millimetre measurements as well as carat weight when comparing diamonds.
Which of the 4Cs Is Most Important?
There isn't one answer for everyone.
However, for many customers, we recommend starting with:
1. Cut
Because it has a significant effect on sparkle and brilliance.
2. Colour
Choose a colour that looks right for the diamond shape and setting.
3. Clarity
Look for a diamond that is clean to the eye rather than automatically paying for the highest clarity grade.
4. Carat
Choose the size that fits your desired look and budget.
The best diamond isn't necessarily the one with the highest grades. It's the one that gives you the combination of beauty and value you're looking for.