What are the 4 C’s?

The quality of diamonds is translated in the 4 C's:

The 4C's specify the quality of a diamond and are used to identify stones.


The weight and size of a stone is expressed in carat.


Colours range from D, colourless, to Z, the yellowest.


Most diamonds are born with birth marks, known as inclusions.


Cut refers to a diamond’s proportions, symmetry and polish.


All investments carry risk and all investment decisions of an individual remain the responsibility of that individual.


The weight and size of a stone is expressed in carat. 1 carat is 0,2 gram and divided into 100 points (or 200 milligram). This scale is very precise in giving a stone's weight and is rounded up to two decimals.

The correlation between carat weight and diamond value can be surprising. The higher the carat weight, the more unique and the higher priced. That’s the reason why a 2 ct diamond has not twice, but the triple value compared to a 1 ct diamond.

The carat of a diamond has also a symbolic meaning. While the visual difference between a 0.98 ct and a 1.01 ct diamond is hardly visible, the price of the 1.01 ct will be noticeably higher. We can explain this price difference by the fact that some weight are considered as “magic sizes”: e.g. one carat, one and a half carat,…

BAUNAT recommends diamonds ranging from 1 Carat to 5 Carats


The colour of a white diamond stone is determined thanks to an internationally recognized colour pallet. Colours are graduated from D, colourless and the most searched for, to Z, the yellowest. The colour of a diamond has a strong correlation with the value of the diamond.

Diamonds can also be brown, orange, pink or blue... The most intense colour shades are named 'fancy' and this is mentioned on their certificate. These coloured diamonds are extremely rare and therefore very precious, but also more speculative. Our experts noticed that the market becomes remarkably smaller for reselling a very rare diamond (colorful, very large, fancy shapes). It requires more time to resell such diamonds at a desirable price.

BAUNAT recommends D, E, F, G for white diamonds


Most diamonds are born with birth marks, known as inclusions. A loupe or microscope (x10 enlargement) are used to determine the clarity of a stone. This means that flaws that cannot be seen at this enlargement are considered as non-existing. The fewer flaws are present, the more rare, the higher the value of the diamond. Inclusions can also interfere with the brilliance of a diamond, as inclusions may stop the reflection of light within the diamond. Most importantly, inclusions should not detract from the beauty of a stone. Therefore we select only diamonds with inclusions that cannot be seen with the naked eye.

Two types of impurities:

The clarity of the diamond can be flawed in two ways:

External impurities: the blemishes occur during the cutting process or are due to wear
Internal impurities: these inclusions relate to any flaws within the stone. Many types exist.

Most common inclusions:

Black or dark spots: which originate in the coal
Clouds: microscopic veils which weaken the clarity
Feathers: most impurities in diamonds come out of the molecular break during the creation process of a stone from coal

BAUNAT recommends clarities higher than VS2 and up to Flawless


Cut is a diamond's most important characteristic. It is the factor that fuels a diamond’s fire, sparkle and brilliance. Cut refers to a diamond’s proportions, symmetry and polish. If the depth of the diamond is too shallow or too deep it will allow light to escape through the sides or the bottom of the stone. A well-cut diamond will direct almost all the light through the crown, making the diamond a brilliant stone.

BAUNAT only works with Very Good and Excellent cut diamonds

Cut quality

The Round Brilliant Cut is the most sought after cut in the world. It owes its appeal to its superior brilliance. The Round Brilliant Cut is a mathematically engineered shape with 58 facets that is conceived to maximize light return. Thanks to its predefined form, it is possible to grade the cut as a whole. Grades range from poor to excellent. BAUNAT only works with very good to excellently cut diamonds.

Fancy cut

The term “cut” can also describe the shape of a diamond. Other shapes than the standard round brilliant cut are called fancy cuts. The most known are the princess, cushion, pear, oval, heart and emerald cut.

Our diamonds

With the largest selection of certified diamonds in the world, we offer the 10 classic diamond shapes, from 1.00 ct and above. All our high quality diamonds are ethically sourced and certified by a leading international diamond grading organization such as GIA, IGI and HRD.

Start to invest See our selection of loose diamonds