When you first hear about gemology, you might wonder if it is an art or a science. We will detail below the first bases necessary for the apprentice gemologist or quite simply for the lover of precious stones.
What is gemology?
According to Larousse, gemology is “the science of identifying the nature of gems and characterizing their decorative use”. The definition is too restrictive. The identification of gems remains the backbone of gemology, but its areas of competence or influence are much broader. Gemology is also used by the lapidary, the buyer or seller of stones, museums, auction rooms, appraisals, etc. You will find more general information on gemology on the dedicated gemology page .
There is Decree No. 2002-65 of January 14, 2002 which legislates on a number of definitions relating to gemology in France. As part of a diploma course in gemology, it is essential to know these articles and in general all the laws in your country. Fortunately for amateurs, this is not the case, unless you decide to resell a stone …
What is a gemologist?
A gemologist is a specialist in gemology. If we only take into account the basic definition of gemology, the role of the gemologist would be reduced to identifying stones and indicating their use in decoration or jewelry.
The gemologist also intervenes to certify gems during auctions, legal appraisals, customs procedures, trading, jewelry design, estimates, etc. Moreover, buyers of stones from large jewelry houses often have basic training in gemology. This gemological skill is acquired through solid training and a lot of practice. We will detail in detail what a gemologist is in the chapter ” the gemologist “.
After several years spent with my friends from AFG on their stand in Sainte Marie aux Mines, the demand from individuals and sometimes professionals mainly concerns the confirmation of the nature of the stones purchased, the estimation of their price and their use in lithotherapy or mystical art. This last question comes up more and more frequently with the development of alternative therapies.
What is a gem?
A gem is the “general name of precious stones and transparent fine stones” according to Larousse. This definition is a starting point, but it is too broad on one side and too restrictive on the other. For example, a good quality jade is generally considered a gem when it is not transparent. Poor quality sapphire, even if it is fairly transparent, is not a gem. So what is a gem? A gem is a material used in decoration or ornament to which we associate the criteria of beauty, rarity, durability and market value. A gem can therefore be cut, polished, engraved or even rough! Let’s see in the chapter “the gems” in more detail what is called a gem.
What Are Crystal Systems
There are 7 crystal systems on Earth (which have an ordered internal structure), to which amorphous materials are added (no internal ordered structure). It is interesting to understand what these systems are because they are the ones that will give some of the characteristics of the gems that we are studying. For example, the cubic system, of which diamond and spinel are a part, implies that these two gems cannot present two different colors on the dichroscope.. If we observe two colors with a dischroscope, then we can conclude that the studied gem cannot be part of the cubic system! We will therefore eliminate diamonds, spinels, fluorites, etc. of the diagnosis. Crystalline systems also exhibit other properties which we will detail in the “crystallography” chapter..
What is a gemological analysis?
Identifying a gem is actually like a police investigation. We collect clues that will allow us to validate certain hypotheses and rule out others. It is very important to have a structured approach. It is also a question of understanding why one practices such or such test on a gem and what one expects from it. Each school has its own process, just like every gemologist. I present to you my gemological analysis process in the Practice section .
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the instruments
the practice
the documentation
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