The KLENOTA certificate carries basic information about the jewellery purchased, namely what kind of jewellery it is, the type of metal used including its weight, as well as details about any gemstones set into it. With diamonds, we always indicate the clarity, colour and the carat weight. The date of issue and the total weight of the jewellery is also stated on the certificate and this may differ slightly from the weight stated in the description of the jewellery on the website due to the nature of handcrafted work. This certificate serves as both proof of purchase and a warranty certificate, so it is advisable to keep it in case you need to get any alterations or repairs to the jewellery
An international certificate from a gemological laboratory
Any jewellery with natural as well as laboratory diamonds which weigh over 0.30 ct is also certified by an international gemological laboratory.
The Gemological Institute Of America (GIA)
The GIA is an American nonprofit organisation dedicated to research, education and consumer protection in the diamond, gemstone and pearl industries. It was founded in 1931 and it’s considered the most important gemological laboratory in the world. In professional circles, it is considered an authority and a source of new scientific knowledge and standards. Among other things, it was behind the birth of the highly regarded and famous “4Cs” method of assessing diamond quality.
IGI (International Gemological Institute)
The IGI is the second most important institute dealing with precious stones. In addition to loose gemstones, it’s expertise also lies in evaluating finished jewellery pieces. It was founded in 1975 in Antwerp, Belgium, the cradle of the diamond trade. Its activities also cover outreach and education.
HRD (Hoge Raad voor Diamant)
HRD Antwerp is a renowned laboratory that guarantees quality right in the heart of the diamond city of Antwerp. It also has offices in Mumbai and Istanbul. The company's history dates back to 1973, when the Diamond High Council foundation was created at the instigation of the Belgian government and representatives of the diamond industry. In 2007, it split into two companies, one of which (the AWDC) deals with trade and production, while the other (HRD) specialises in diamond certification.
The work of a gemologist
A very difficult part of a gemological specialist's job is to select the right gemstones. When it comes to earrings, this is often a challenge that’s twice as hard. Hundreds of stones frequently have to be sorted through by hand. It’s little wonder when you consider how many factors influence the appearance of a mineral. It's hours of meticulous work, but it contributes significantly to the excellence of our jewellery.
What an international certificate tells you about a diamond?
Each diamond passes through the hands of experts and undergoes careful analysis using the most modern techniques. A certificate from a renowned laboratory is a guarantee about the particular properties of a diamond which show how good an investment it might be in the future. We will have a look at what such a certificate contains by using a specific example, namely the Diamond Origin Report from the GIA, which is designed to evaluate colourless diamonds.
First of all, the certificate lists the date it was issued, the identification number, the shape and cut of the diamond, and the very precise dimensions of the stone. With any diamonds in a brilliant cut, the diameter and depth are described while for the other shapes, the length, width and depth are described. This is followed by an assessment of the four basic characteristics of diamonds, which are collectively known as the 4Cs.
The weight (carat)
The weight of diamonds is given in carats, with one carat defined as 200 mg. Carat weight is discussed in more detail in the article What is a carat and how does it affect the value of diamonds.
Colourless diamonds are graded based on the presence of any unwanted coloration with letters on a scale from D to Z used. At the KLENOTA jewellery studio, we normally set diamonds graded G into jewellery (which appear completely colourless under normal conditions) into jewellery. Read more about the colour of diamonds in our article The color grading of natural clear diamonds.
This parameter assesses the presence of any internal inclusions and external flaws in a diamond. The number, size, position and nature of these minor flaws are assessed, as well as the overall impact on the diamond's appearance. KLENOTA jewellery is typically set with diamonds of SI clarity.
The cut is graded out of a possible five grades, the best of which is Excellent and the worst is Poor. When grading the cut, the type of cut, its size in relation to weight, the symmetry of the individual facets and the quality of their polish are all taken into account. For more information on diamond cuts, check out the article Gemstone shapes and why shape and cut are not the same thing.
In addition to the parameters of the 4Cs, there is also a more detailed assessment of several other diamond characteristics, namely lustre, symmetry and fluorescence.
The certificate also includes two diagrams. The first is a visual representation of the proportions of the diamond’s cut. It’s actually a sort of enlarged model of the diamond in 2D where you can see the angles of each facet. The second diagram shows the inclusions, their size, type and location. GIA certificates come with several security features which prove their authenticity. By scanning the embedded QR code, you can verify the information for a specific diamond directly in the GIA database.