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What is gemology?

Gemology is a branch of mineralogy that deals with the study, identification, classification and evaluation of gemstones. It is a fascinating and complex science that involves geological as well as physical, chemical, and optical aspects. Gemologists are specialized experts who focus on the study and analysis of gemstones.

The role of gemological institutes

Gemological institutes are institutions specializing in the research and analysis of gemstones. Their main task is to determine the authenticity and quality of gemstones and issue certificates that serve as reliable references for buyers, collectors and jewelers. These institutes have state-of-the-art laboratories with specialized equipment to perform comprehensive analysis of gemstones.

There are many laboratories worldwide that examine and evaluate gemstones. Each laboratory publishes its own classification reports based on its own norms and standards.

Below is an overview of some independent institutes and laboratories that issue internationally recognized certificates for colored gemstones and diamonds:

- GIA: Gemological Institute of America
- IGI: International Gemological Institute
- GRS: GemResearch Swisslab
- HRD Antwerp: Institute of Gemology

In Germany there are also prestigious gemological institutes that have a long tradition and reputation. Such as:

- DSEF: German Foundation for Gemstone Research


The duties of a gemologist

A gemologist is an expert in the field of gemstones and has extensive training in mineralogy, geology, and other related fields. The main duties of a gemologist include:

- Identifying gemstones and determining their origin.
- Evaluating the quality, purity, and color of gemstones.
- Examining gemstone properties, such as hardness, density, and optical effects.
- Detection of treatments or alterations to gemstones.
- Preparation of expert opinions and issuance of certificates for gemstones.


The appraisal of gemstones

Appraising gemstones is a precise process that requires careful examination. Gemologists use advanced laboratory techniques, such as spectroscopic analysis, microscopy and X-ray diffraction, to determine the characteristics of a gemstone. Color, cut, clarity and weight are all taken into consideration. The results of the analysis are then incorporated into the certificate.

Below we explain the steps a gemologist goes through when appraising a gemstone:

   1. external appraisal:

The gemologist begins with a careful external inspection of the gemstone. Here he looks at the shape, cut, proportions and surface of the stone. He checks to see if the gemstone may have any damage, scratches, chips, or wear.

   2. color examination:

The color of a gemstone is one of the most important criteria for its evaluation. The gemologist assesses the color quality and saturation of the stone. He often uses special color scales to determine the exact color of the gemstone.

   3. interior view with light source:

The gemstone is illuminated with a light source to analyze its optical properties. The gemologist examines the refraction, dispersion, light absorption and transparency of the stone. This information helps identify the gemstone and may indicate possible treatments or inclusions.

   4. Microscopic examination:

Under a microscope, the gemologist can take a closer look at the gemstone. Here he looks for internal features such as inclusions, cracks, or growth structures that may be characteristic of certain gemstones.

   5. spectroscopy:

Spectroscopy is a crucial tool in gemology. It allows the gemologist to analyze the light spectrum of the gemstone. Each gemstone has a characteristic absorption spectrum that aids in its identification.

   6. hardness testing:

To determine the hardness of a gemstone, the Mohs scale is commonly used. The gemologist uses other minerals with known hardnesses to test whether the gemstone remains scratch or damage free or can be easily scratched.

   7. density or specific gravity measurement:

The density of a gemstone can also provide important clues to its identity. The gemologist uses special measuring equipment to determine the specific gravity of the stone and compare it to known values.

   8. X-ray diffraction and special tests:

In some cases, more advanced examination methods such as X-ray diffraction or other special tests may be required to identify the exact gemstone type or possible syntheses.


Preparation of the expert opinion and certificate

Based on the results of the examinations, the gemologist prepares a detailed appraisal and certificate for the gemstone. The appraisal contains all the important information about the identification, quality, possible treatments and other special characteristics of the gemstone.

It is important to emphasize that gemology is an ever-evolving science, and gemologists must continually educate themselves to keep up with the latest technologies and developments in the field. Their expertise is critical to ensuring the authenticity and quality of gemstones and maintaining the trustworthiness of the gemstone market.

The cost of a certificate from a gemological laboratory can vary depending on the extent of the examination and the procedure used. For example, the price range of the DSEF is between 130-600 euros. However, the price can also be significantly higher for particularly valuable or rare gemstones.

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The certificate as a seal of quality -

: Certificate for your gemstone

As a serious and responsible gemstone dealer, we at attach great importance to the certification of our gemstones. Therefore we let, on your request, the gemstone tested by the DSEF and issue you the certificate on account.

Inhouse certificates from

You have the possibility to have the authenticity and quality of your gemstones confirmed by We issue certificates upon request when you purchase our colored gemstones, which can serve as proof for your customers.

Selina Krug, Customer Service employee, explains transparently how goes about creating in-house certificates:

"First, the stone is placed under a refractometer."

Brief explanation: a refractometer is a measuring device used to determine the refractive index of gemstones. The refractive index helps identify gemstones because each gemstone has a characteristic refraction of light.

"In our quality inspection, the gemstone to be examined is once again closely examined under a magnifying glass and all the characteristics of the stone are determined. For this purpose, I examine the stone closely and inspect it for inclusions. Then the gemstone is weighed with a special carat scale and the measurement is taken again. After careful quality inspection, I fill out the certificate."

This certificate states which gemstone it is, its color, weight, shape, and cut type, as well as the size, quality, and degree of hardness. Furthermore, the country of origin is confirmed and whether and how the gemstone was treated for refinement.

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You would like to get a certificate when buying a colored gemstone?

Select this directly during your order process or contact us and we will issue a sound certificate!

Prices: For an ordered value of goods between 1 - 1.000 Euro we charge 20 Euro for the in-house certificate. For an ordered value of goods above 1.000 Euro the certificate is free of charge.

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Overall, gemology is a fascinating science that provides us with insights into the fascinating world of gemstones. The work of gemological institutes and gemologists is of great importance to ensure that when we buy gemstones, we receive trustworthy information and can properly appreciate their beauty and value.

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