Beauty and the Data: The Modern Gem Lab
By Dr AL Barnard [Gemdrop]
Imagine placing a ruby beneath a microscope.
To the untrained eye, it is simply beautiful: red, transparent, intensely coloured, perhaps worth hundreds or thousands of pounds. But to the scientist sitting behind the microscope, the ruby is something more. It is a record…
Inside it may be curved growth structures left by a furnace, microscopic crystals trapped millions of years ago, healed fractures, trace elements incorporated during crystallisation, or chemical signatures introduced deliberately by human treatment. What appears at first to be an object of beauty becomes, under scientific examination, a complex physical history waiting to be read. This is the world of the modern gemological laboratory. And remarkably, it is a world only about a century old.
In 1925, B. W. Anderson was charged with establishing what would become the world's first specialised gemological laboratory in London. Its original problem was comparatively narrow but economically urgent: distinguishing natural pearls from the new bead-cultured pearls entering the market. Early investigators relied upon ingenious combinations of optical examination and X-ray (Anderson, 1981; Scarratt, 2026). From that beginning grew an entirely new scientific enterprise.
A Science Built by Curiosity
The early gem laboratory would look almost modest beside its modern descendant. Its essential tools included refractometers, microscopes, spectroscopes, immersion liquids and careful human observation. Yet simplicity does not necessarily mean limited capability.
During the economic depression of the 1930s, Anderson and his colleague C. J. Payne used a period of reduced commercial work to investigate the fundamental optical and physical properties of gemstones. They refined measurements of refractive index and specific gravity and contributed to the development of improved refractometers for practical gem testing (Anderson, Payne and Pike, 1940; Burbage and Anderson, 1942; Scarratt, 2026).
There is something deeply instructive in this episode. Science does not always advance through spectacular discoveries. Sometimes it advances because somebody decides that an accepted number in a textbook ought to be measured again. That instinct — show me the data — became part of the intellectual foundation of the gemological laboratory.
Then the problems became harder.
Synthetic ruby had existed since the nineteenth century, but by the middle of the twentieth century gemologists realised that manufactured gemstones could no longer be treated merely as scientific curiosities. Synthetic rubies had entered jewellery markets, followed by increasingly sophisticated synthetic sapphires, emeralds, alexandrites, opals and, eventually, diamonds.
The laboratory therefore entered an extraordinary technological race. Every innovation in gemstone growth or treatment created a new analytical problem. Every new analytical problem demanded another experiment.
Microscopy revealed growth structures. Spectroscopy revealed absorption features. X-ray diffraction identified crystalline materials. Ultraviolet-visible spectroscopy exposed optical behaviour. Fourier-transform infrared spectroscopy, or FTIR, provided access to structural and molecular information that conventional gemological instruments could not reveal. Raman spectroscopy emerged as another powerful, largely non-destructive analytical technique, while chemical methods such as energy-dispersive X-ray fluorescence (EDXRF) and, later, laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) pushed laboratories towards increasingly precise trace-element analysis (Nassau, 1981; Scarratt, 2026). The gem laboratory was becoming something very different from a jeweller’s back room. It was becoming an analytical science laboratory.
When the Gem Fights Back
One of the most compelling aspects of gemology is that its scientific problems are created by a constantly moving target. Consider what happened in 2002. An unfamiliar colour treatment began appearing in corundum, the mineral family that includes ruby and sapphire. Researchers established that beryllium had been diffused into the material at high temperature, producing dramatic changes in colour (Emmett et al., 2003; Scarratt, 2026). The problem was that the instrumentation routinely used by many gem laboratories could not adequately detect the element responsible. The gems had, in effect, outrun the laboratories.
The response was better science. Researchers investigated techniques capable of detecting beryllium, including laser-induced breakdown spectroscopy, or LIBS (Krzemnicki, Hänni and Walters, 2004). Major laboratories subsequently adopted LA-ICP-MS, which could not only detect beryllium but measure its concentration alongside other trace elements. This allowed laboratories to assess whether the beryllium present was naturally occurring or associated with a diffusion treatment (Scarratt, 2026). The episode captures something essential about the modern gem laboratory. Its purpose is not simply to possess expensive instruments. Its purpose is to ask, and answer, increasingly complex questions.
Seeing the Invisible
Today, a gemstone submitted to a sophisticated laboratory may encounter an extraordinary range of analytical technologies. A gemologist may begin exactly as predecessors did decades ago: with their eyes and a microscope. But the investigation can then move far beyond ordinary human vision.
Raman spectroscopy can investigate molecular and crystal-lattice vibrations. FTIR spectroscopy can reveal structural characteristics and evidence of treatment. UV-visible-NIR spectroscopy can help explain colour. Trace-element analysis can provide evidence concerning growth environment or geological origin. Digital photomicrography can combine numerous focal planes into a single image with exceptional depth of field, a technique made increasingly practical through digital image-stacking software (Nassau, 1981; Piper, 2010; Scarratt, 2026).
Even pearls — the problem that helped create the gemological laboratory a century ago — can now be examined using real-time digital X-radiography and X-ray micro-computed tomography. Rather than relying solely on a two-dimensional radiograph, researchers can reconstruct internal structures in three dimensions and examine them virtually, slice by slice (Karampelas et al., 2010; Krzemnicki et al., 2010). A pearl can therefore remain intact while a scientist explores its internal structure. A ruby can yield detailed chemical information through microscopic sampling. A diamond can reveal defect-related spectral features associated with its formation or subsequent treatment.
That is an astonishing scientific achievement.
Yet the Most Important Instrument Is Still Human
It would be easy to tell the history of gemological laboratories as a history of machines. That would miss the point.
Behind every refractometer, spectrometer, microscope and mass spectrometer stands a person deciding what to measure, how to measure it and, most importantly, what the measurement means.
The history described by Kenneth Scarratt is populated by scientists and gemologists including Anderson, Payne, Gübelin, Liddicoat, Crowningshield, Koivula, Bosshart and many others who combined rigorous observation with extraordinary curiosity. Edward Gübelin’s pioneering use of inclusions as indicators of gemstone identity and origin, for example, developed into an extensive body of published work and eventually the Photoatlas of Inclusions in Gemstones series produced with John Koivula (Gübelin, 1953; Gübelin and Koivula, 1986, 2005, 2008).
Successive generations continually adopted technologies that their predecessors could scarcely have imagined. One story captures this spirit particularly well. Researchers had discovered that cooling diamonds sharpened certain features in their visible absorption spectra. According to the account related by Scarratt, Anderson would walk to London’s Smithfield meat market to obtain dry ice, returning with it in his briefcase so that diamonds could be cooled for spectroscopic examination. As he walked back to the laboratory in his three-piece pin-striped suit, the briefcase reportedly became increasingly frosted (Scarratt, 2026). It is an almost absurd image, but also an excellent example of bleeding-edge science. You have a question. You have an experiment. You find a way to perform it.
The Laboratory of the Future
The challenges facing the next generation of gemologists will be different again. Laboratory-grown gems continue to develop. Gemstone treatments continue to evolve. Questions of geographical origin increasingly intersect with concerns over traceability, environmental responsibility and supply chains.
Modern origin determination also depends increasingly on rigorously documented reference collections. In 2008, GIA’s Bangkok laboratory established a dedicated Field Gemology Department under Vincent Pardieu, with systematic collection and documentation of samples from mining areas forming an important part of its work. Such collections provide the comparative data against which unknown stones can be studied (Pardieu, 2020; Scarratt, 2026). GIA reported the completion of its hundredth field-gemology expedition in 2025 (GIA, 2025).
At the same time, increasingly large analytical datasets are opening opportunities for machine learning and artificial intelligence in gemstone classification, origin research and the interpretation of complex analytical data (Scarratt, 2026).
Yet none of these developments diminishes the role of the scientist. They make it more important.
Artificial intelligence may recognise patterns across thousands of spectra. Instruments may detect elements at concentrations unimaginable to the pioneers of the 1920s. Automated imaging systems may generate data with extraordinary speed.
But instruments produce measurements. Science requires interpretation, judgement and an understanding of uncertainty.
The modern gemological laboratory therefore represents something larger than gemstones. It demonstrates how knowledge progresses.
A question about pearls leads to X-rays. A problem with synthetic ruby advances microscopy. A treatment involving a difficult-to-detect element pushes laboratories towards new forms of chemical analysis. A desire to understand where a gemstone formed sends scientists into mines around the world to assemble rigorously documented reference collections.
Each generation inherits the observations of the previous one and then encounters a problem its predecessors could not solve.
Scarratt closes his century-long history with Isaac Newton’s famous acknowledgement that scientific progress comes from “standing on the shoulders of giants” (Scarratt, 2026). After one hundred years of gemological laboratories, the phrase feels particularly appropriate.
The extraordinary analytical capabilities available today exist because generations of researchers measured, questioned, photographed, experimented, argued, published and measured again.
Perhaps that is the most inspiring thing about entering a modern laboratory. You are surrounded by instruments capable of revealing worlds hidden from ordinary human perception. And the beauty of the gems is surrounded by the beasts of unanswered questions. Somewhere among those questions may be one whose solution belongs to the next scientist curious enough to ask it.
References
Anderson, B.W. (1981) ‘The growing pains of gemmology’, Journal of Gemmology, 17(8), pp. 515–521.
Anderson, B.W., Payne, C.J. and Pike, J. (1940) ‘New refractometers employing diamond and other minerals’, Mineralogical Magazine, 25(170), pp. 579–583.
Burbage, E.J. and Anderson, B.W. (1942) ‘An analysis of the movements of the shadow-edge on the refractometer in the case of biaxial gemstones’, Mineralogical Magazine, 26(178), pp. 246–253.
Emmett, J. et al. (2003) ‘Beryllium diffusion of ruby and sapphire’, Gems & Gemology, 39(2), pp. 84–135.
Gemological Institute of America (GIA) (2025) GIA Field Gemology Team Completes One-Hundredth Expedition: Visit to Tanzania and Kenya Marks 17 Years of Rigorous Scientific Study.
Gübelin, E.J. (1953) Inclusions as a Means of Gemstone Identification. Los Angeles: Gemological Institute of America.
Gübelin, E.J. and Koivula, J.I. (1986) Photoatlas of Inclusions in Gemstones. Zürich: ABC Edition.
Gübelin, E.J. and Koivula, J.I. (2005) Photoatlas of Inclusions in Gemstones 2. Basel: Opinio.
Gübelin, E.J. and Koivula, J.I. (2008) Photoatlas of Inclusions in Gemstones 3. Basel: Opinio.
Karampelas, S. et al. (2010) ‘X-ray computed microtomography applied to pearls: Methodology, advantages and limitations’, Gems & Gemology, 46(2), pp. 122–127.
Krzemnicki, M. et al. (2010) ‘X-ray computed microtomography: Distinguishing natural pearls from beaded and non-beaded cultured pearls’, Gems & Gemology, 46(2), pp. 128–134.
Krzemnicki, M.S., Hänni, H.A. and Walters, R.A. (2004) ‘A new method for detecting Be diffusion-treated sapphires: Laser-induced breakdown spectroscopy (LIBS)’, Gems & Gemology, 40(4), pp. 314–322.
Nassau, K. (1981) ‘Raman spectroscopy as a gemstone test’, Journal of Gemmology, 17(5), pp. 306–320.
Pardieu, V. (2020) ‘Field Gemology, the evolution of data collection’, InColor, 46, pp. 36–42.
Piper, J. (2010) ‘Software-based stacking techniques to enhance depth of field and dynamic range in digital photomicrography’, in Hewitson, T.D. and Darby, I.A. (eds.) Histology Protocols. Totowa, NJ: Humana Press, pp. 193–210.
Scarratt, K. (2026) ‘The Evolution of the Modern Gemological Laboratory’, Journal of Gems & Gemmology, May 2026. Republished by Lotus Gemology, 18 May 2026.