Diamond Education

What Are the 4 C's?

Cut, Colour, Clarity and Carat are the universal language for assessing a diamond. Understand them and you will never overpay for something you cannot see.

The 4 C's Colour Clarity Cut Carat Weight Certification

What Actually Makes a Diamond

Every diamond in the world is graded on these four characteristics. Together they decide how a stone looks, how rare it is, and what it costs.

LIGHT IN, BRILLIANCE OUT

The First C

Cut

Cut is not the shape of the diamond. It is the quality of the cutting itself: the angles, proportions and symmetry of every facet. It decides how much light travels into the stone and bounces back out to your eye.

Get it right and a modest stone throws fire across the room. Get it wrong and light leaks straight out of the bottom, leaving a diamond that looks flat and glassy no matter how good its other grades are.

Our Advice Never compromise here. Excellent or Very Good, every time.
Learn About Cut →
D–F G–J K–M N–R S–Z COLOURLESS NEAR COL. FAINT V. LIGHT LIGHT RAREST MOST AFFORDABLE

The Second C

Colour

Colour measures how little colour a diamond has. The scale runs from D, completely colourless, down to Z, where a warm yellow tint is obvious to anyone. The closer to D, the rarer and more expensive the stone.

Here is the part most people are never told: once the stone is set in a ring and viewed face up, the difference between neighbouring grades is almost impossible to see. You are paying for rarity on paper, not beauty in the hand.

Our Advice G to I looks colourless once set and costs far less than D to F.
Learn About Colour →
10× MAGNIFICATION

The Third C

Clarity

Clarity grades the tiny internal marks, called inclusions, that formed while the diamond grew. Grades run from Flawless down to Included, and almost all of it is judged under 10x magnification rather than with the naked eye.

That distinction is where the money is. An inclusion you physically cannot see without a loupe has no effect on how the ring looks on her hand, but it can cut thousands off the price.

Our Advice Buy eye-clean, not flawless. VS1 to SI1 is the value sweet spot.
Learn About Clarity →
0.50 ct 0.75 ct 1.00 ct 1.50 ct PRICE CLIMBS FASTER THAN SIZE

The Fourth C

Carat Weight

Carat is weight, not size. One carat is 0.2 grams. Because price climbs exponentially rather than in a straight line, a two carat stone costs far more than twice a one carat stone of the same quality.

Prices also jump hard at the round milestones. A 0.95 carat diamond looks identical to a 1.00 carat on the hand and can save you a serious amount, simply because it sits under a number buyers ask for by name.

Our Advice Buy just shy of the milestone. Nobody can see 0.05 of a carat.
Learn About Carat →

How We'd Rank the Four

If your budget is fixed, and everyone's is, this is the order that gets you the best looking ring for the money.

Cut
Never Skimp
Carat
Buy Just Under
Colour
G to I
Clarity
Eye-Clean

Three Rules Worth Remembering

Every buyer has a different priority. These are the recommendations we give most often, and the ones that save people the most money.

01

Prioritise Cut Above All

A poor cut kills a diamond's brilliance no matter how good its colour and clarity look on paper. This is the one grade you can genuinely see across a room.

02

Colour Is a Setting Decision

G to I looks colourless to the naked eye once mounted. In yellow or rose gold you can drop to J or K happily, because the metal warms the stone anyway.

03

Eye-Clean Beats Flawless

If you need a loupe to find the inclusion, it does not affect the ring. We inspect every stone with you at 10x so you know exactly what you are buying.

No Pressure, Ever

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the Perfect Diamond

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