Diamonds 4C's Ultimate Guide

If you are considering buying a diamond, educating yourself about the factors that determine diamond quality before buying will not only save you money but ensure you get the best bang for your buck. To aid you, therefore, we have put together this guide to help you. Learn about the 4C's (Cut, Colour, Clarity, and Carat) to make the most of your diamond shopping experience since its price will be fully determined by the 4Cs.


There is a common misconception that Carats and Sizes refer to the same thing; Size refers to the millimetre size of the diamond, whereas Carat refers to its weight in grams.

Here is an example showing how the carat unit is used. Take two diamonds that are both 1 ct. If the first one is cut very deep, it will look closer to a 0.80ct stone than an average 1ct one. If the second one is instead cut very shallow, the size of the diamond may look closer to a 1.25ct stone at the expense of its quality. Therefore, a 1ct diamond that looks good will also weigh 1ct.

Quality is always compromised whenever diamonds are cut too deep or too shallow, resulting in a diamond that cannot achieve its full brilliance and sometimes appears dark or lifeless.


Clarity, the first of the 4 Cs, refers to the diamond's 'clearness'. A Clarity grade indicates how common or big the inclusions (imperfections) are in a diamond.
The Clarity grades, according to GIA, are as follows:

Flawless (FL), Internally Flawless (IF)

The highest grade a diamond can get when it comes to clarity. Flawless (FL) and Internally Flawless (IF) diamonds have no visible inclusions inside the stone when viewed through 10x magnification. However, unlike Flawless (FL) diamonds, Internally Flawless (IF) diamonds may have some surface marks (blemishes) under 10x magnification.

Very Very Slight Inclusions (VVS1 & VVS2)

VVS1 and VVS2 are the next highest clarity grades. Although a lower tier than FL and IL, the very tiny inclusions in VVS1 and VVS2 diamonds are incredibly difficult, even to gemologists and diamond experts, to see under 10x magnification. Pinpoints, needles, or internal graining could be some of the inclusions that may be present in a VVS diamond.

Very Slight Inclusions (VS1 & VS2)

Although lower in grade than VVS1 and VVS2, VS1 and VS2 grade diamonds are still eye-clean. VS1 and VS2 clarity diamonds have slightly larger inclusions than the VVS range. The inclusions are difficult to see in (VS1) but somewhat easier to spot in (VS2) if looked through 10x magnification. VS diamond's inclusions include crystals, cavities, or clouds.

Slight Inclusions (SI1 & SI2)

SI1 and SI2 clarity diamonds have more prominent inclusions than the VS diamonds. To the trained eye, these inclusions are noticeably visible under 10x magnification. SI diamond might have inclusions are chips, knots, and feathers.

Included (I1, I2 & I3)

I1-I3 clarity diamonds are the bottom grade in clarity. They have much more pronounced inclusions that are easily noticeable to the naked eye. Large inclusions like the ones found in I clarity might affect the brilliance of the diamond.

Novita's Recommendation:

Novita Diamonds recommend you get the finest looking diamond your budget allows. To ensure that the inclusions in the diamond are not visible to the naked eye, even when looked closely, we recommend you limit your choices to diamonds that are VS1, VS2 and SI1 and above in order to ensure that inclusions in the diamond are not visible to the naked eye.


Colour is the simplest of all 4Cs because a Diamond Colour grade describes how colourless the stone is. The best diamonds are the ones without any colour in them, allowing their brilliance to shine through. The whiter or, to be precise, the clearer the stone is, the more valuable it becomes. As the colour grade lowers, tints of other colours, such as yellow or brown, start to be become noticeable, decreasing their overall value. The diamond colour grades by GIA goes from D (colourless) to Z (light yellow or brown). To simplify the process, diamond grades are grouped into different tiers because untrained eyes may see very little difference between diamonds with a 1 or 2 colour grade difference.

D,E,F (colourless)
What are D-F grade diamonds? They comprise the highest grade of Colour and also the rarest. Being colourless, D and F diamonds are extremely clear and bright and have no yellow or brown tints whatsoever. D and F are grouped as colourless since when placed in a setting, they will both look the same, at least to an untrained eye. To differentiate between a D diamond and one that is F, both stones must be loose and compared to each other on a pure white background.

G,H (near colourless)
What are G-H grade diamonds? Almost as good as D and F, G-H are grouped together as near colourless. Although they have a very faint tint of Colour, in practice, it is not very noticeable at all to the naked eye. When in a setting, they will appear more or less white and still look colourless. Only when loose and compared to colourless diamonds, however, will the very slight tint in the stones be noticeable.

I,J (very faint Colour)
What are I-J grade diamonds? More common and of lower quality than the previous two tiers, they are grouped together as having a very faint colour. When compared to diamonds in the colourless or near colourless categories, I-J diamonds have a slightly more noticeable yellow, brown or grey tint. Anything lower than a J colour will have a significantly more noticeable yellow, brown or grey tint in the diamond.

Recommended by NOVITA: Since D-F colour diamonds are all very clear and colourless, they look very similar to each other to the untrained eye; therefore, there aren't any pressing reasons to pick a D coloured diamond over an E or F, other than personal choice. In general, if the diamond has a colour of at least F, more of the budget can be used to get a better cut and shape.

Although they are relatively affordable and plentiful, G-H colour diamonds are very good choices as they are nearly colourless, making them good "budget stones". By purchasing G-H diamonds, you can get a much larger stone than you would have been able to get when purchasing a D-F diamond.
Recommended by NOVITA: You can save money or get a larger stone instead by choosing diamonds that are D-G in Colour.


It is impossible to overlook the importance of the Cut grade when considering the 4Cs. The importance of a good Cut cannot be understated since it has the most significant effect on a diamond's appearance. The sparkle, fire, and brilliance that are all qualities associated with diamonds are all dependent on the Cut. If a diamond is not well proportioned, i.e. if it is cut too deep or too shallow, it will result in the light entering the stone, leaking out of the bottom of the diamond. A diamond should bounce light back up from the bottom rather than leak out the sides or bottom; otherwise, it will appear dull and lifeless. Diamonds that are cut properly are brilliant in appearance. The light that enters a well-cut diamond reflects off all the sides, or facets, of the diamond and comes straight back up, imparting a scintillating and otherworldly appearance to the diamond. Even high-quality diamonds of every other category can appear dull and lifeless if their cut grade isn't high enough.

Recommended by NOVITA: Be sure to always purchase diamonds with an Ideal Cut or Excellent Cut.

Novita Diamonds Guidance:

We have carefully selected our showroom options so that we only offer you the best quality diamonds in our HK showroom and for online purchases. Our gemmologists sort through available diamonds and only choose the best diamonds in each colour and clarity category. Please feel free to come into our Hong Kong showroom to get additional guidance on choosing the best stone for you or your loved ones.

Our Novita website allows you to filter your diamond search by the 4Cs categories, as shown below.

Select ‘AVAILABLE IN SHOWROOM’ in the tab menu and check ‘SHOWROOM’ in the column to further filter our available lab grown diamonds in Hong Kong.

To learn more about lab grown diamonds HK visit our home page, where we go in depth about lab grown diamonds.