There has been a growing trend among many gem and jewelry professionals that there is a mystical box that laboratories use that will, at a moments notice, produce the results of any gemstone, revealing its identity, treatments, or even where in the world it may come from. Since most testing is done behind closed doors, I thought it would be helpful to shed some light on what actually happens when gemstones undergo analysis. Although this short article isn’t meant to provide a comprehensive step-by-step, it will give the reader a better idea of the various tests that are involved and why a seemingly simple analysis can take hours or even days to complete.
Some gemstones are more laborious and thought provoking than others, but the lineage of tests, for the most part, remain somewhat the same in the beginning. But what is it that we are looking for and where do we start? If there is one common denominator among gemologists when testing a gemstone, it would be OBSERVATION. Physical observation is absolutely critical before determining anything definitive about a gemstone. Many clients will ask when submitting a gemstone, “How long will this take?” I, most often, will request to see the stone first, so I can take a quick glimpse under a microscope before I give them an indication of when they could expect their results. That first peek into the fascinating world of internal and surface characteristics can be infinitely helpful in providing a mental check list of tests that will need to be performed. Looking for things such as: body color, inclusion types, growth features, specific patterns that are present within a break, or the sharpness of facet junctions, for example, are all clues to the nature of the tiny pebble in question and the many mysteries it might possess. Moving forward, I might obtain a refractive index and check for other simple optical properties such as light polarity, pleochroism and/or fluorescent reactions. Although not too time consuming, the results can be indicative and sometimes even conclusive based on a couple or more of these tests alone; however, most often, this isn’t how it works out.
Some gemstones are inherently challenging to determine certain attributes about its identity. Differentiating synthetic quartz or synthetic alexandrite from their natural counterpart for instance, or even identifying some types of polymer fillers, low temperature heating, or the country of origin are other examples in an endless list that may require a much more sophisticated arsenal of tests.
– Enter the “magic machines” –
Spectrometers and spectrophotometers as they are more commonly referred to, are used to study the properties of light emitting through or reflecting from a given material. By using different types of lasers and/or various wavelengths of light, used in conjunction with finely tuned sensors, the material in question produces a signature of sorts, unique to the very nature of its chemical and structural makeup. I won’t go into the principles of how and why it works (another article, maybe,) but I will say, without these wonderfully complicated pieces of equipment, a lot of what gemologists do on a daily basis wouldn’t be possible. With that in mind, and much to some people’s surprise, there is no magic involved. In fact, without the proper training and a fair understanding of chemistry and physics, these mystical boxes would only serve as very heavy, and enormously expensive paperweights. The dozens or even hundreds of scans that the gemstone in question is subjected to will ultimately yield what can only be assumed to be a manic line graph of squiggly bumps and dips, all of which are representative of the specimens structural and chemical identity. The time and patience it takes to learn and recognize such patterns can take years to master, and with an ongoing onslaught of new treatments and technologically advanced synthetics emerging into our growing market, this field of study is never ending and requires a lot of time and education, not to mention ongoing personal research, gaining as many reference samples as possible.
So there you have it. A modest glance into the analytical world of gemstone testing and identification. Although there are many points of interest which could not be addressed within the scope of this article, I hope this demystifies, even if just a small bit, the process your gemstones undergo when submitted for testing. I hope this article sparks your analytical curiosity and I encourage the reader to openly ask questions to help better understand this captivating field of study.
