5C diamonds for choosing the perfect jewel
The diamond is exceptional for its brilliance and luminosity. It is prized for its ability to reflect light dazzlingly, creating unparalleled sparkle and brilliance. One of the aspects that make this gemstone stand out from other gemstones is that its quality can be determined based on certain standards.
For this reason, in this article we will explain what their fundamental characteristics are through the so-called 5Cs, those that lead a person to make the right choice of a product. diamond jewellery.
The 5Cs: the quality of a diamond
Colour, colourless to yellow
Although diamonds in their purest state are colourless, the colour of diamonds can vary if foreign elements or inclusions are present.
To determine the colour of a diamond, there are several colour scales in the colourless series, as these gems are the most commonly used in jewellery. The oldest and most traditional is the one used in the Scandinavian standard, which consists of nine grades: River, Top Wesselton, Wesselton, Top Crystal, Crystal, Top Cape, Cape, Light Yellow and Yellow.
The Gemological Institute of America (GIA), currently the most widely used in Europe, is also noteworthy. It does not use names, but the colour values go in alphabetical order, from D (colourless) to Z (yellow).
The International Confederation of Biscuit, Jewellery and Goldsmiths (CIBJO) has also created its own scale, which consists of eight grades and respects the limitations of the above scales: Exceptional White +, Exceptional White, Extra White +, Extra White, White, White with light colour, Light Colour and Colour.
Diamond colour scales
| Scandinavian | GIA | Antwerp | CIBJO |
|---|---|---|---|
| River | D | 0+ | Exceptional white + |
| E | 0 | Exceptional white | |
| Top Wesselton | F | 1+ | White extra + |
| G | 1 | White extra | |
| Wesselton | H | 2 | White |
| Top Crystal | I | 3 | White with slight colour |
| Crystal | J | 4 | |
| Top Cape | K | 5 | Slightly coloured |
| L | 6 | ||
| Cape | M | 7 | Colour |
| N | 8 | ||
| Light Yellow | O | 9 | Colour 2 |
| P | 10 | ||
| Yellow | Q | 11 | Colour 3 |
| R | 12 |
Carat, the weight of a diamond
The weight of diamonds is expressed in carats. In this sense, a carat is one-fifth of a gram, which means that a diamond weighing one gram has five carats. The figure indicating the weight of a diamond is expressed as the number of carats to two decimal places, called hundredths or points. For example, a 0.30 ct diamond is a diamond of thirty hundredths or points.
Clarity, the purity of a diamond
When we talk about the purity of a diamond, we are referring to the inclusions of other minerals that it may have due to its formation process. Likewise, the degree of purity is always catalogued with a 10x magnification magnifying glass.
The purity scale of a diamond ranges from a diamond that has no purity defects at all, referred to by CIBJO as 10x purity, to a diamond that has a high purity defect that is usually visible to the naked eye.
Diamond purity scale
| GIA |
|---|
| FL |
| IF |
| VVS1 |
| VVS2 |
| VS1 |
| VS2 |
| SI1 |
| SI2 |
| I1 |
| I2 |
| I3 |
- FL: Flawless
- IF: Internally flawless
- VVS: Very very small inclusions
- VS: Very small inclusions
- YES: Small inclusions
- P: Piqué
- I: Imperfect
Cut, the diamond cut
Cut is the determining factor of a diamond's brilliance and includes two concepts, the shape of the diamond, and the quality of the proportions and finish.
The most common diamond cut is the brilliant cut. There are others, such as emerald, princess and oval.
Shiny size
The modern brilliant cut was structured after the publication in 1919 of a theoretical study by Marcel Tolkowsky. This study established the correct angles to be given to the facets of the crown and the butt with respect to the girdle plane. Also, the ideal proportions for this carving to present the maximum brilliance and dispersion.
In this sense, the brilliant cut consists of an upper part, called the crown, and a lower part, the butt. Both are joined by an irregular band, the girdle. The apex of the butt usually ends in a point, although sometimes it may be slightly truncated, carving a tiny facet called a culet.
This carving is the most used and traditional, as well as having a spectacular lustre. Its term can be used in isolation. Therefore, when it is said “it is a brilliant”, it is taken for granted that it is a brilliant cut diamond.
Source: GSE
Certificate, the diamond certificate
As for the fifth C: certificate, there are some leading international organisations for this certification. Those awarded by the laboratories of the Gemological Institute of America (GIA), the Hoge Raad voor Diamant (HRD) and the International Gemological Institute (IGI) are highly regarded internationally for their completeness.
It is important to ensure that the stone matches the certificate when valuing a certified diamond, whether it is mounted or loose. It is also important to take into account any damage that may have occurred after certification. This is why the visual analysis should be carried out with a 10x magnification loupe.
