Christopher P. Smith is one of the most respected figures in applied gemmology, serving as President of the American Gemological Laboratories (AGL) in New York City. Trained at two of Europe's foremost gemmological institutions — the Swiss Gemmological Institute (SSEF) in Basel and the Gübelin Gem Lab in Lucerne — Smith brought a rigorous, laboratory-science foundation to AGL that has shaped the organisation's methodology and reputation over several decades. His particular expertise lies in the geographic origin determination of coloured gemstones, the detection and disclosure of treatments, and the application of advanced analytical instrumentation to stones that resist easy classification. In the trade and at major auction houses, an AGL report bearing his involvement is regarded as a mark of serious scientific scrutiny.

Training and Early Career

Smith's formation as a gemmologist followed a path that was, at the time, unusual for an American practitioner: he pursued his advanced studies in Switzerland rather than through the domestic GIA route. The SSEF, under the direction of Henry Hänni, was already establishing itself as a centre of excellence for spectroscopic and chemical analysis of coloured stones, while the Gübelin Gem Lab — founded by Eduard Josef Gübelin, whose landmark work on inclusions remains foundational to the field — offered unparalleled grounding in inclusion microscopy and provenance research. This dual Swiss training gave Smith direct exposure to the European tradition of treating each gemstone as an individual geological specimen rather than as a commodity to be graded against a standardised scale.

Upon joining AGL in New York, Smith brought these methodologies into an American commercial context, where the laboratory's clientele includes dealers, collectors, auction specialists, and estate appraisers requiring documentation that can withstand scrutiny in high-value transactions.

Areas of Expertise

Smith's published work and professional reputation centre on three interlocking disciplines:

• Geographic origin determination. Establishing whether a ruby originates from Mogok (Myanmar), Mong Hsu, or Mozambique, or whether a sapphire is Kashmiri, Burmese, or Sri Lankan, requires the integration of inclusion microscopy, ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) trace-element analysis, and a deep comparative reference database. Smith has contributed to refining the criteria used for several of the most commercially significant origin calls in the coloured-stone market.
• Treatment detection. The identification of heat treatment, fracture filling (with glass, resin, or flux), beryllium diffusion, and surface coating in rubies, sapphires, and emeralds is among the most consequential work a laboratory performs, directly affecting a stone's market value by orders of magnitude. Smith has been involved in documenting and publishing on the emergence of new treatment types as they have entered the trade, including the widespread use of lead-glass filling in heavily fractured rubies — a phenomenon that required laboratories worldwide to update their detection protocols in the mid-2000s.
• Emerald assessment. Emerald presents particular challenges because virtually all natural specimens contain fractures that have been treated with oils, resins, or polymers to improve apparent clarity. AGL employs a grading scale for the degree of clarity enhancement in emeralds, and Smith has been instrumental in communicating the scientific basis of this system to the trade.

Research and Publications

Smith has contributed articles and research notes to Gems & Gemology, the peer-reviewed quarterly published by the Gemological Institute of America, which is the primary English-language journal of record for gemmological science. Publication in Gems & Gemology subjects findings to editorial and peer review, lending them a credibility that distinguishes them from trade-press commentary. His contributions have addressed topics including origin criteria for specific ruby and sapphire localities and the analytical signatures of particular treatment types.

Beyond the written record, Smith lectures internationally at industry conferences and educational programmes, translating laboratory findings into practical guidance for dealers, appraisers, and auction specialists who must make rapid commercial judgements about stones they cannot analyse themselves.

AGL and Its Position in the Laboratory Landscape

The American Gemological Laboratories occupies a distinctive position among the handful of internationally recognised coloured-gemstone laboratories — a group that also includes the Gübelin Gem Lab, SSEF, Gemmological Institute of America (GIA), and the Laboratoire Français de Gemmologie (LFG). While GIA is the dominant authority for diamond grading, the coloured-stone market has historically distributed its trust among several specialist laboratories, each with particular strengths and regional relationships. AGL has built its reputation specifically on coloured-stone origin and treatment reports, and under Smith's leadership has maintained the scientific investment — in instrumentation, reference collections, and trained personnel — necessary to keep pace with an increasingly sophisticated trade.

AGL reports are routinely accepted by the major international auction houses, including Sotheby's, Christie's, and Bonhams, as supporting documentation for significant coloured-stone lots. In the context of a ruby or sapphire that may sell for tens or hundreds of thousands of dollars per carat, the laboratory report is not merely a formality: it is the primary instrument by which buyer and seller establish a shared understanding of what, precisely, is being transacted.

Significance in the Trade

The broader significance of practitioners such as Smith lies in the role that credible, independent laboratory science plays in maintaining market integrity for coloured gemstones. Unlike diamonds, for which the 4Cs provide a widely understood and relatively standardised framework, coloured stones are evaluated through a complex interplay of origin, treatment status, colour quality, and individual character. The determination that a ruby is of Burmese origin with no indications of heat treatment — the combination that commands the highest premiums in the market — rests entirely on the laboratory's analytical rigour and the professional credibility of the gemmologists who sign the report. Smith's career represents the sustained application of that rigour to some of the most consequential stones passing through the American and international markets.

Further Reading

• Gems & Gemology — GIA's peer-reviewed gemmological journal (gia.edu)
• American Gemological Laboratories (aglgemlab.com)
• Swiss Gemmological Institute SSEF (ssef.ch)
• Gübelin Gem Lab (gubelingemlab.com)