Arrow Fat Left Icon Arrow Fat Right Icon Arrow Right Icon Cart Icon Close Circle Icon Expand Arrows Icon Facebook Icon Instagram Icon Hamburger Icon Information Icon Down Arrow Icon Mail Icon Mini Cart Icon Person Icon Ruler Icon Search Icon Shirt Icon Triangle Icon Bag Icon Play Video
Download your free ebook "Choosing the perfect diamond" Download your free ebook "Choosing the perfect diamond"

Understanding The Four C's

In the Diamond industry, the Four C's are generally accepted as the key benchmarks to measure a quality diamond. The Four C's - Cut, Colour, Clarity, Carat weight - impact a diamond's appearance and value.

Cut - How a diamonds' facets interact with light.

Colour - The less colour (i.e. yellow tones) a diamond has, the more valuable it is.

Clarity - How few (or many) internal and external marks the diamond has.

Carat - The standard unit of weight for diamonds.

See below for more detail on each of the Four C's.


Cut is the most important consideration when buying a diamond. It refers to how a diamonds’ facets interact with light. This affects its brightness, fire (how the light disperses on the diamond) and sparkle (scintillation). We recommend buying the highest cut grade within your budget. A diamond’s cut is graded on a scale: excellent, very good, good, fair, poor.

Cut vs Shape

Often ‘cut’ and ‘shape’ are used interchangeably, but shape is the outline of the diamond—round diamonds are the standard shape and all other variations are ‘fancy’.


Colourless diamonds are most desirable—they refract the most light so they sparkle more. Diamonds with more colour don’t refract light as well and sparkle less. The Gemological Institute of America’s (GIA) colour scale begins at D (a colourless stone) all the way to Z—each lower grade indicates more colour in the diamond. At DeRocks, we stock diamonds in the D to G range (the higher end of the scale).


Diamonds are formed naturally deep in the earth under intense pressure and heat so they often contain ‘birthmarks’ that are either internal (inclusions) or external (blemishes). The clarity of a diamond refers to the absence of these inclusions and blemishes. The GIA’s clarity scale assigns a clarity grade ranging from flawless to diamonds with obvious inclusions.


Carat is the standard unit of weight for diamonds and other gemstones. Large diamonds are much rarer than smaller ones, so the price of a diamond rises exponentially in relation to its size.

Whilst the Four C's are undoubtedly important in determining the quality & value of a diamond, there are other factors that significantly influence a diamonds value. To make sure you make the right decision when buying a diamond, we recommend that you download our comprehensive ebook for a more in detailed analysis of diamonds.

Additional Resources

How to choose a high quality diamond.

Diamond Fluorescence: why its so important.

Diamond Certification: Don't buy a diamond without it.