Each diamond is sold with a certificate, a birth certificate that guarantees the buyer that the diamond is genuine and of high quality. This certificate is issued by a world-renowned gemological laboratory (GIA) and includes a 4C diamond evaluation.


When diamonds are evaluated and certified, the basic parameters of diamonds, such as cut, carat, clarity and color, which have a significant impact on the diamond price, are assessed. These parameters are referred to as 4C.


Basic 4C parameters



Carat (indicates the weight of the diamond)




Brush is a very important feature of a diamond. The raw stone does not look dazzling in any way. Diamonds are cut into many so-called fancy shapes: awning, baguette, heart, teardrop, oval, and rocker aka the emerald brush. Between the different cuts, however, the dominant position occupies a round diamond with eight-dimensional symmetry.



The diamond is the only precious stone that occurs in nature in almost all color modifications. The most common are colors ranging from white to yellow. These colors are included in the international diamond color scale, which is referred to with the Latin alphabet D-Z.

Color specification is performed by experts using a Master Stones set - they compare each rated diamond with them.

Did you know that there are also colored diamonds, called "fancy" diamonds? They are rarer and can be red, pink, blue, yellow, orange, green or brown. Yellow is the most common color, and pink, red, blue and green diamonds are very rare.



The weight of the diamond is given in carats (ct). In diamond certificates, you'll find the weight of the diamond accurate to 2 decimals.

1 ct = 200 mg = 0.2g

Did you know that the carat unit comes from medieval marketplaces? In order to balance the precious stones, the seeds of the locust bean (carob) were used, which are all equally heavy.

Did you know that it is a different carat than gold? Gold's karat is abbreviated "kt" and denotes the purity of the gold.



The purity of the diamond is determined by the number of foreign substances contained in the observed diamond. These inhomogeneities may have intrinsic characteristics - they are called inclusions (dark "carbon", white "ice", cracks, etc.) that originated in the various phases of crystal formation. Furthermore, they may be external characteristics (scratches, superficial faces, naturals, etc.) that have been created by machining or otherwise cannot be removed by machining.

The magnitude and distribution of these characteristics depend on the assignment of the appropriate grade of purity for the observed diamond. As a standard for measurability, a magnifying glass is used with ten times magnification.


International scale of diamond clarity

The purity of the diamond is marked as "loupe-clean" if, under specified conditions, the diamond meets the condition of absolute transparency without inclusion.

VVS * (Very Very Small) (VVS 1, VVS 2)

Extremely small inclusions that are very difficult to detect with magnification of 10x.

VS * (Very Small) (VS 1, VS 2)

Very small inclusions that are very difficult to detect with magnification of 10x.

SI * (Small Inclusions) (SI 1, SI 2)

Small inclusions easily detected by magnifying glass with 10x magnification, but invisible to the naked eye from the crown side of the abdomen.

PI (Pique)

Medium inclusions visible without problems at 10x magnification but difficult to see with the naked eye from the crown side of the abdomen, disturbing brilliance.

P II (Pique II)

Large and numerous inclusions, very easily detected by the naked eye from the crown side of the abdomen, slightly reducing the brilliance of the diamond.

P III (Pique III)

Large and numerous inclusions, very easily detected from the naked eye of the crown of the abdomen, which reduce the diamond brilliance.



Sources used:

Gia.edu. (2016). Diamond Quality Factors. [Online] Available at: http://www.gia.edu/diamond-quality-factor [Accessed 6 Dec. 2016].