The Gubelin Gem Lab is independent, legally and operationally. It is wholly owned by Gubelin Holding, which itself is wholly owned by the Gubelin family, currently in its seventh generation. The Gubelin family owns other businesses in the jewellery sector, among them Gubelin AG, a retailer with seven watch and jewellery shops in Switzerland. The Gubelin Lab started out as an integral part of this retail operation. When it started testing gemstones for auction houses and other external clients, the decision was made to give it its independence with its own shares, structure and management. This separation provided the Gubelin Gem Lab with the autonomy it needed to ensure complete confidentiality and thus gain the trust of the trade. The confidentiality that we grant our clients is such that the management and staff of Gubelin AG and other entities of the Gubelin Group do not have access to the Lab premises.
Consumers today care where the products they buy come from. This is not restricted to geographic origin alone. Their concern includes the background of the stone, the conditions under which it was mined, traded and processed, the environmental and social sustainability of the production and trade, as well as compliance with human rights. Consumers want proof that their purchase has created value for those who really contribute to the final product. Their money must not end up with rogue regimes or failed states, or in the hands of warlords, terrorists and suchlike.
The gemstone industry has come to realise that having a properly set gemstone is not enough. It must also accompany the purchase with credible information offering the consumer peace of mind. For a few years now, many industry players have been launching initiatives aimed at establishing structures that give the transparency today’s consumers are asking for. The scope and target of these initiatives include fair trade, fair manufacture, environmental sustainability, fair wages, human rights compliance and avoidance of armed conflict financing. These initiatives usually attempt to scrutinise the conditions present at each step of the value added chain, from the mine, via the sorting, cutting and testing operations, to the ultimate sale. The best-known such initiative is the Kimberley Process: introduced by the United Nations, it aims to ensure that rough diamonds come from sources where conflict is not financed by diamond production. If done properly, wrongdoers can be identified and banned from the market. Aside from schemes certifying a specific origin, such as the Kimberley Process, other initiatives are premised on a fully controlled and closely monitored mining and trading process. The aim of most of these schemes is not fair trade alone, but the acquisition of market share by building brands that consumers can trust.
While most gems are minerals, i.e. of inorganic origin, some gem material is of organogenic origin, meaning that it was produced by a living organism. Examples of organogenic gems are pearls, ivory, amber and coral. CITES (the Convention on International Trade in Endangered Species of wild fauna and flora, also known as the Washington Convention) is an international resolution by the International Union for Conservation of Nature (IUCN) that aims to monitor the international trade in specimens of wild animals and plants so as to safeguard their survival. More than 33,000 species of animals and plants are listed, including a few species which are known for their gem material. For example, some coral species (C. elatius, C. japonicum, C. konjoi and C. secundum) are protected under CITES Appendix III (Fish and Wildlife Service, 2008). Meanwhile, the Stylasteridae family, which includes all Stylaster gem corals, are listed under CITES Appendix II (as of January 18, 1990), which means that a certificate issued by the management authority of the country (or state) of export is required. Another species listed in the CITES Appendix is the queen conch mollusc, which produces conch pearls. The African elephant – often hunted for its ivory – is another, more prominent, species protected by CITES.
Whenever the Gubelin Gem Lab encounters gem material originating from an animal species listed by CITES, a note is issued specifying the protected status of the species in question.
Our scientific researcher, Dr. Stefanos Karampelas has recently published an article about this subject.
The origin determination of gemstones is a branch of gemmology that compares the gemmological properties of a stone of unknown origin with the gemmological properties of stones from known reference sources. Origin determination has its limits and cannot be carried out on all types of stone, or for every stone of a certain type. In a series of articles that appeared in 2006 in Jewellery News Asia, we described these limitations, stressing the fact that, for certain types of stone, some origins produce stones showing properties that are very similar to stones from other origins. We have been aware of these similarities in gemmological properties for many years, the partial overlap of these properties, and thus the risk of confusing two (or more) origins. To address this issue, we conduct scientific research on authentic samples from these sources, and try to find criteria (single or combined) to distinguish the various origins. This might or might not lead to the desired result.
If the properties of a stone of unknown origin cannot be attributed unequivocally to one source only, then the only professional conclusion is to leave the origin undetermined. Generally, to be in the position to determine an origin, two conditions must be met: first, the properties of the unknown stone must be consistent with those from those stones from our reference collection which come from one specific origin, e.g. Burma. Secondly, the combination of properties of the unknown stone must be different from the combination of properties of reference stones from all other origins. In other words, the unknown stone must exhibit a sufficiently high similarity with a stone from country A, and must be different from country B, C, D, etc. If only one of these two conditions is fulfilled, we do not issue an origin.
The truth is that none of us witnessed the stone being taken from the mine, which would be the direct proof of the stone’s origin. Thus we are restricted to the indirect method of comparison with reference stones as explained, for example, in the three JNA articles mentioned under Origin Determination. The scrupulous application of this methodology allows us to arrive at a professional and educated judgement as to the origin of a stone. Furthermore, in the JNA articles, we propose a list of criteria that have to be met to ensure a certain degree of Origin Determination quality and reliability. However, what we (and other laboratories) express in our reports is indeed not an absolute truth, but a professional opinion, no more and no less. At the end of the day, it is the client who has to decide whether to place confidence in the opinion.
The same applies to other information in the report, such as treatments, colours etc. The Gubelin Lab, like other gem laboratories, expresses professional opinions on gems. This opinion is based on the analyses conducted and the experience and knowledge of the gemmologists, and takes into account the latest research published in professional scientific journals.
The truth is that none of us witnessed the stone being taken from the mine, which would be the direct proof of the stone’s origin. Thus we are restricted to the indirect method of comparison with reference stones as explained, for example, in the three JNA articles mentioned under Origin Determination. The scrupulous application of this methodology allows us to arrive at a professional and educated judgement as to the origin of a stone. Furthermore, in the JNA articles, we propose a list of criteria that have to be met to ensure a certain degree of Origin Determination quality and reliability. However, what we (and other laboratories) express in our reports is indeed not an absolute truth, but a professional opinion, no more and no less. At the end of the day, it is the client who has to decide whether to place confidence in the opinion.
The same applies to other information in the report, such as treatments, colours etc. The Gubelin Lab, like other gem laboratories, expresses professional opinions on gems. No more and no less. This opinion is based on the analyses conducted and the experience and knowledge of the gemmologists, and takes into account the latest research published in professional scientific journals.
Gem laboratories are service providers to the gem industry. We are not partners in a commercial sense – we do not share the risks and rewards of our clients’ businesses. Of course, it would be unacceptable for gem laboratories to be involved in the sale of a stone: we do not share in a client’s potential profit or loss on a stone. This limits our liability when it comes to the potential financial impact of a deal. We are required to conduct the analysis fully and diligently, and we are obliged to maintain the highest standards of scientific expertise, professional diligence and ethical integrity.
The world’s laboratories are subject to few standards in terms of the methods and processes they deploy. The Gubelin Gem Lab supports the idea of defining specific criteria which gem laboratories must meet in order to carry out, for example, origin determination. The most obvious would be to define the type of analysis that must be performed. The definition of a required standard of analytical method is feasible and would ensure a certain level of standardisation. The Gubelin Gem Lab has already started to promote such steps within the framework of the LMHC. We strongly believe that the standardisation of analytical methods will reduce the number of conflicting reports between laboratories.
Another issue is the standardisation of the interpretation of analytical results. This task is far more complex. The comparison of analytical data acquired on two different machines is, alas, very difficult to correlate, and is feasible only to a very limited extent for a number of reasons. One of these reasons is as follows: usually, the reproducibility of quantitative analytical data acquired by a specific machine is very good, whereas its accuracy is limited. This is an in-house issue that confronts every laboratory whenever it replaces an analytical machine – or just a component (x-ray tube, detector) – with a new one. In this event, the raw data will be affected and requires adjustment for it to be comparable with the existing data. It is an issue multiplied many times over if there is a need for standardisation across several laboratories. For example, it is currently virtually impossible to reasonably compare quantitative chemical data which has been acquired on two different machines in different laboratories. That said, the latest generation of instruments offering quantitative chemical analysis is likely to be more reliable in this respect, and the comparison of data generated on different machines might become easier. The same applies to the interpretation of microscopic observations. For these reasons, we believe that the harmonisation of the interpretation of analytical data is not something that will happen any time soon, even across a restricted number of laboratories.
We provide our clients with the end results of our analysis, i.e. our conclusions vis-a-vis the interpretation of the analytical results referenced against our reference stones and in the light of the current status of gemmological research. We do not currently grant access to the raw analytical data, mainly because of the limited comparability of the raw data acquired by different machines. Again, while reproducibility is usually very good, accuracy is limited, and comparing raw data from one laboratory with those from other laboratories is hard to achieve and could be misleading. In addition, a conclusion is based on much more than a single observation (a peak in a spectrum, a weight percentage of a chemical element, a single microscopic observation). Usually, it is the combination of many different observations extracted from various analytical techniques that leads to a final conclusion (see also the final article in our JNA series: A holistic method for determining gem origin). Taking one or a few observations and using them out of context to draw conclusions is potentially misleading.
Our clients may rest assured that we continually update the portfolio of analytical equipment we use at our headquarters in Lucerne – and abroad when Off-Premise Testing with the mobile laboratory. For the last 20 years we have used UV-Vis spectrometers for clients’ stones and have applied chemical analysis by means of ED-X-Ray Fluorescence (XRF) for about 15 years.
More recently, we have acquired a Laser-Ablation-ICP-MS system, which extends our capability to carry out quantitative chemical analysis of major and minor elements, trace elements and ultra-trace elements even more accurately.
When Off-Premise Testing abroad, we also apply a wide range of analytical methods. We have used UV-Vis spectrometry for more than 10 years to complement microscopic analysis and the standard gemmological tests such as refractive index, specific gravity, UV luminescence, and so forth. We have also used infrared-spectrometry (FT-IR) for several years in our testing abroad. Our latest acquisition is a mobile XRF system to conduct chemical analysis during OPT. In other words, even when testing away from the laboratory, we diligently apply the same trilogy of analytical testing as at home: microscopy, spectroscopy and chemical analysis. We believe that the quality of analysis we carry out outside Switzerland may be compared favourably to that available at our headquarters in Lucerne. If the available data does not provide us with the required level of certainty and unambiguity, we do not issue a report. In that event, we ask the clients to submit the stones to Lucerne for further testing.
The Gubelin Lab is in the privileged position of owning an extensive collection of reference samples. This collection was started by the late Dr. Eduard Gubelin and has been continued over the decades by his successors. Our reference collection consists of several tens of thousands of samples culled from every one of the world’s commercially relevant mines, whether still active, exhausted or closed long ago.
The acquisition of authentic samples is a major challenge for laboratories undertaking origin determination. We handle this issue as follows: we accept the fact that it is not always possible to collect a sample directly from the primary deposit (which would involve a Gubelin gemmologist taking the stone personally out of the host rock). Quite often, we obtain stones directly from a mine owner, or we buy them either from a dealer near the mine or the adjacent gem market. We are very much aware that we can be deceived even when buying close to the mine: by way of example, we have been offered African stones at the central market in Mogok and have even found synthetic corundum inside (!) the mines of Ilakaka. There is no such thing as “absolute certainty”. We have therefore chosen to apply a system of cross-checks before considering a stone to be a true reference sample. This system works as follows: first, we try to get samples directly from the source, i.e. we send someone from our team to the mine to get samples from within the mine or from the mine owner. In addition, we get samples from various other channels (traders, dealers, etc.), who must be independent of each other. Once we have assembled the samples from these various sources, we conduct analyses to determine whether the properties of these samples can be shown definitively to agree or match. Alternatively, if there are stones which do not match the general pattern, there might be reason to believe that the sample is not really what it is supposed to be. The more independently sourced samples we have, the easier it is to spot exemplars which do not fit into the overall picture. We have applied this system for many years, and as a consequence feel confident in the credibility of our samples. In addition, we have assigned a “credibility factor” to each of our samples in the reference collection.
We make a significant investment every year to keep our collection updated and adopt low-profile methods of acquiring new reference stones. We are in the fortunate position of having samples collected at times when newer sources (e.g. Madagascar) were not yet producing. The provenance of every sample/reference stone is very carefully checked and recorded and we are confident that our collection methods and documentation systems are completely reliable.
