What Do the 4c's Mean?

As the most precious and sought-after stone in the world, diamonds contain far more than meets the eye. Every diamond ring, wedding band and piece of fine jewellery's value depends on four key qualities that determine how it looks and how much it sparkles.

Diamond Heaven brings you this guide to understanding the Four Cs, so that by the end you'll be able to shop for your special stone with the confidence of an expert.

What are the Four C's?

The Four Cs stand for colour, cut, clarity and carat. Together, they create the full picture of any stone you'll ever consider. Once you understand these four qualities, you'll know exactly what you're paying for, where to spend and where to save.

Colour: White, colourless and tinted

The Gemological Institute of America (GIA) grades diamond colour on a scale from D to Z. D is the rarest grade and is completely colourless. Z shows a noticeable yellow or brown tint.

Colour scale grades

 

Once a diamond sits in a ring, the difference between a D and G graded diamond is almost impossible to see with the naked eye. If you're looking for the smartest value - particularly for engagement rings - consider grades G to J. They offer a bright stone for considerably less money.

Fancy colours

Bright coloured diamonds in shades of yellow, pink, blue and black fall under a different category: fancy diamonds. The GIA grades these on hue, tone and saturation rather than the D to Z scale. The more vivid the colour, the rarer and more valuable the stone becomes.

Cut

Cut is the quality that brings a diamond to life. It refers to the proportion, symmetry and polish of the stone, which together control how light moves through it. When you choose an excellent cut, the diamond returns light beautifully through the top of the stone, creating three optical effects:

• Brilliance: the return of white light

• Fire: the dispersion light into rainbow colour

• Scintillation: the sparkle you see as the diamond moves

The GIA cut scale

The GIA grades of cut are marked out of five levels:

• Excellent

• Very good

• Good 

• Fair

• Poor

An Excellent cut diamond performs at its full potential whatever its colour or clarity. A poorly cut stone with top colour and clarity grades will always appear duller than a well cut stone with lower grades. 

Cut has the most impact on a diamond's overall look, so it should be prioritised over the other 4Cs where possible. 

Cut and shape

Cut and shape mean different things. The cut describes the craftsmanship, whereas the shape is the outline of the stone from the top down. The most well known shape is the round brilliant diamond which gets an official cut grading from GIA, while other fancy shapes include cushion, marquise and emerald. 

Clarity

The process that creates a diamond - under high pressure and temperatures in a lab or beneath the earth's crust - leaves a fingerprint on the stone. These consist of natural marks known as inclusions when they occur inside the stone, or blemishes on the surface. The GIA measures clarity by how visible these are under 10-times magnification.

 

 

Diamonds graded VS to SI often represent the wisest choice for buyers who want to maximise their budget. The inclusions remain invisible without magnification and look flawless in everyday wear.

Carat: weight, not size

Carat measures a diamond's weight. One carat equals 0.2 grams or 100 points; therefore, a half-carat stone weighs 50 points and a three-quarter carat weighs 75 points.

Prices rise sharply as weight increases because large rough diamonds are rare. This is why a 2ct diamond costs significantly more than two separate 1ct diamonds.

Magic sizes

Certain weights carry a premium price because demand peaks at round numbers. You can save money by choosing a diamond 0.1cts less than a magic number as you'll find it looks almost identical to the next size up.

• 0.50ct

• 0.75ct

• 1.00ct

• 1.50ct

• 2.00ct. 

Which is the most important of the 4Cs?

No single C creates a stunning diamond on its own. However, cut deserves the top spot in your budget, as it controls overall sparkle. Colour and clarity can be balanced against your overall priorities, whilst carat depends on your desired size and budget. 

How can Diamond Heaven help? 

At Diamond Heaven, our expert team looks beyond technical grades to help you find the perfect diamond. We take the time to understand your style, priorities and budget so you can take home a piece that you'll wear and cherish for years to come.