Gemology, which includes, among other things, the field of gemstone identification, is a science that requires specialized studies and long-term experience. The separation of gemstones from imitations and synthetic materials is a very important skill which professional gemologists are often called upon to use in the modern market.
The diamond is perhaps the most famous and coveted gemstone that commonly “dresses” a single-stone ring. As such a stone, there are numerous imitations of it on the market, each one with its own characteristics. A diamond expert uses various techniques to identify the diamond, based on the properties of the diamond itself and differentiating them from those of the imitations.
How do we distinguish the diamond?
To the specialist’s experienced eyes, the appearance of the stone being examined under special lighting provides the first clues to its identity. Diamonds have a specific brilliance and luster that derives from its exceptional physical properties, namely its hardness, toughness, and chemical stability. Therefore, the way diamond reflects light is very different from that of any other stone. Also, the combination of the natural properties with the style and cut quality of the diamond creates a certain “fire” in the diamond that is different from other stones. Knowledge of this characteristic helps the expert in identification. (By “fire” we refer to the combination of rainbow colour flashes in the iris colours seen in the cut stones).
In addition to the lustre and brilliance, the hardness of diamonds is also evident in their surface. To cut and polish diamonds, diamonds require special handling, as well as expertise and equipment that we do not use for any other stone. Only diamonds can scratch diamonds, so the cutting and polishing disc we use must be covered with diamond dust. The result from this cutting process is perfectly polished facets, very clear corners and sharp edges between the facets. These are surface features that we only find in diamonds.
Other important characteristics of diamonds
Diamonds, because of the natural environment in which they grow, contain certain enclosed characteristics. These characteristics help the diamond expert to distinguish the diamond from imitations and from synthetic materials that may contain different types of inclusions.
Additional tests we use to identify the diamond include measuring the specific gravity of the material if it is not set in a jewel, fluorescence under ultraviolet light, transparency, and analyses that are only performed in properly equipped gemological institutes, such as spectrometry among others.
Although there are basic differences between diamonds and their imitations, identification is not always easy, and certainly requires expertise and practical experience. Let’s not forget that proper knowledge of the subject and up-to-date education are essential for a professional gemologist, as the gem industry is constantly and relentlessly evolving. Therefore, in case we are not sure about the identity of a stone, it is always safe and right to seek the services of a trained and accredited gemologist.
Eva Kountouraki GG, AJP, JBM
Gemologist – Diamond expert, Jewellery Consultant
