Traceability of Base Metals Ores Using Mineralogical and Microtextural Parameters Julie Machault, Luc Barbanson, Thierry Augé, Laurent Bailly, Jean-Jacques Orgeval

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Julie Machault, Luc Barbanson, Thierry Augé, Laurent Bailly, Jean-Jacques Orgeval. Traceability of Base Metals Ores Using Mineralogical and Microtextural Parameters. 13th SGA Biennal Meeting , The Society for Geology Applied to Mineral Deposits, Aug 2015, Nancy, France. pp.1547-1550. ￿insu-01289689￿

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Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives| 4.0 International License Traceability of Base Metals Ores Using Mineralogical and Microtextural Parameters

Julie Machault, Luc Barbanson Institut des Sciences de la Terre d’Orléans (ISTO), Université d’Orléans/CNRS-INSU/BRGM, UMR 7327, 1A rue de la Férollerie 45071 Orléans Cedex 2, France.

Thierry Augé, Laurent Bailly Bureau de Recherches Géologiques et Minières (BRGM), Direction des Géoressources (DGR/MIN), 3 avenue Claude Guillemin BP 36009 45060 Orléans Cedex 2, France

Jean-Jacques Orgeval 16 Allée du Houx 45160 Olivet, France

Abstract. The demand in mineral resources is increasing All diamonds must be accompanied by a certificate of rapidly, but there is a lack of transparency in the trade of origin (Kimberley process). The development of the concentrates raw mineral materials because of 18O/16O isotopic identity card for emeralds helps to speculation and involvement in the finance of armed distinguish the source of a large number of high quality conflicts. Because of the distance between primary emeralds (Giuliani et al. 1998b). Fingerprints of coltan extraction and the final production sites it is difficult to check the origin of these products. An identity card is can be determined to find the place of origin of the mineral required for mineral commodities, so that trading in the (Gäbler et al. 2011, 2013; Melcher et al. 2008a, b, 2013; industry can be verified and the traceability of Savu-Krohn et al. 2011). A similar need sometimes arises concentrates ensured. This problem may be considered during mineral processing when multiple sources are as an inversion process: studying the products sold to used. The Luossavaara Kiirunavaara AB-plant (LKAB) in identify the original ore. The discriminant parameters are Sweden produces iron ore from Kiruna and Malmberget mineralogical composition, identification of textural mines. These minerals are mixed. Iron oxides of microfacies of the target minerals (pyrite, sphalerite and Malmberget are different from those from Kiruna chalcopyrite), “pseudo-paragenetic sequence”, and the (coarser-grained, different types of joints of grains,…) contents and distributions of minor elements of target minerals. Statistical tests are used to compare the (Oghazi et al. 2009) and behave differently during chemical composition of three target minerals. The treatment. To clarify the importance of the source of the application to Volcanic Massive Sulphide ore deposits ore on the difficulties observed during treatment, a shows that it is possible to distinguish target minerals traceability study was attempted (Kvarnström and Oghazi between ore deposits in the Iberian Pyrite Belt province 2008; Machault et al. 2013). However, there are very few and from the Urals province using the selected studies on the tracea-bility of base metals. These metals characteristics. Ore deposits from different provinces may are mainly used in industrial sectors and the evolution of be discriminated using the identity cards, as well as their price depends to a large extent of the growth of the different deposits in the same province. global economy.

Keywords. Traceability, identity card, target minerals, The aim of this work is to establish parameters to be Volcanic Massive Sulphide included in an identity card for each deposit, which will allow it to be discriminated from other deposits. This Figure 1. Schematic model of the Energy Test Bed 1 Introduction requires a method of traceability with low analytical cost, using easily accessible techniques mineralogical and The scientific impact of this new infrastructure will Acknowledgements Metal mining and marketing have an impact on the microtextural characterization allow an unique signature be far reaching, including understanding of subsurface economy, society (negative or positive) and the to be established for each ore and each deposit studied flows, geoche-mistry and physics of rock matrices, and BGS is funded by the Natural Environment Research environment. The metal market is a major factor in (Machault et al. 2014). The ultimate objective of this the interaction of surface carbon and other geochemical Council (NERC UK). This proposal underpins the economic development. This is a major concern in study, which is part of a global programme to create an cycles and subsurface flows. British Geological Survey strategy (2014). developed countries, which are anxious to secure supplies ore identity card, is the establishment of a database The new infrastructure will act as a catalyst for in view of the strong demand for mobile phones, digital incorporating the characteristics of each deposit and each industry both onshore and offshore to stimulate References tablets, solar panels, batteries, … It is also growing mineral processing plant (Machault et al. 2013). Periodic investment and speed new technology options to concern for the “citizen-consumer”, who needs to be sure reviews of the database will ensure monitoring of commercialisation. It will thus act as a bridge from British Geological Survey (2014) Gateway to the Earth: science for that these items have not been produced contrary to his or traceability parameters over time. the next decade. Keyworth, Nottingham: British Geological ideas to application and would attract support and her ethical or moral values. To avoid parallel markets of possible co-funding from oil and gas companies, mining Survey. Available from http://resources.bgs.ac.uk/ebooks/gateway_to_the_earth/index. certain mineral resources, solutions have been proposed 2 An approach for the traceability of base companies, utilities and energy and environment html#/1/ to locate the extraction sites of these resources for metals in Volcanogenic Massive Sulphide consultancy. diamond via Kimberley Process (www.kimberleyprocess .com), for emeralds (Giuliani et al. 1998a, b), sapphire Traceability refers to the ability to track a product at (Giuliani et al. 2005), ruby (Giuliani et al. 2005) and different stages of its production, its transformation and “coltan” (Gäbler et al. 2011, 2013; Melcher et al. 2008a, its commercialization from the source of the product up to b, 2013; Savu-Krohn et al. 2011). A chain of control and the end of its life, including possible recycling. It must certification has been set up by the diamond producer allow the origin of the source concentrate to be countries under the supervision of international experts. determinated at each of these stages. Procedures to

Sustainable mining and environmental issues 1547 achieve a good traceability are governed by standards identification of characteristics microfacies, the presence 6 Discussion criteria. At this stage of method development, the and/or national or international control organizations. In of trace minerals and finally the minor elements contained establishment of a hierarchy between the retained the case of mineral resources, traceability consists of in the “target minerals”. The “target minerals” are: (1) 6.1. Appropriateness of the methodological characteristics, valid for all VMS deposits, seems associating a commodity to the mine from which it has Pyrite for its ubiquity in the studied bulk ore deposits approach used premature. However we are able to produce flow charts been extracted. For base metals, the bulk ores bear which allows to compare bulk ores from different mines; for each parameter showing their discriminative or mineralogical differences, which may provide (2) Sphalerite, which can incorporate into its structure a We have established an original traceability method for satisfactory features (Fig. 4). characteristics to track the bulk ore. These characteristics large number of potentially valuable elements (Ge, Ag, In, base metals. This traceability method can be used to may “survive” during mineral processing, so that we can Ga) or non-valuable elements (Fe, Cd, Hg, Mn, Sb); (3) obtain a comprehensive identity card of the deposits. find “footprints” of bulk ore in the concentrate. Hence Chalcopyrite that is repeatedly found associated with Mineral chemistry is considered to be the most promising metal ore traceability implies that, in the ideal case, for pyrite and sphalerite. tool for provenance analyses. The comparative results each province and also for each deposit, valuable mineral obtained from the statistical tests (Kolmogorov Smirnov have an unique signature. The characteristics that can be and Colin White) are roughly similar, regardless of the observed in concentrated at grain-scale (mineralogical elements or considered target minerals. Therefore the composition, chemical composition of the phases, Colin White test appears to be the most effective test to microtexture) will depend on (1) the process of formation compare the minor elements content in ore, since (1) it of the mineralization and its post-deposit history (type of necessitates fewer individual data; (2) it is not influenced ore deposit) and (2) the local geological setting including by the value of individual data and (3) it is not sensitive the host rocks (regional setting which is sometimes poorly to element distribution heterogeneity. understood). The concentrate is derived not only from natural processes, but also from industrial processes, 6.2. Utilisation of discriminative parameters for which must be taken into account. In addition to the ore traceability processing difficulties like mixing of bulk ores This study contributes to the establishment of various (Kvarnström and Oghazi 2008) we cannot exclude Figure 1. Organization chart of the method used for variations over time in the operation of a given establishing identity cards parameters that differ from a deposit or a province to mineralurgical plant. Finally, within a given mine, the another. Some of these parameters are discriminative but nature of the bulk ore may vary over time as the 4 Presentation of the metallogenic context a single characteristic is generally not enough to obtain a exploitation of the site progresses. Hence, the signature of of the two studied provinces successful discrimination of all the studied deposits. It is therefore necessary to combine parameters, as provided in the concentrate depends on the characteristics of useful the ore identity card to get a satisfactory result. In our minerals, the type of deposit, the metallogenic province We limit this study to a single type of deposit: case, there is not any unique parameter that could provide Figure 2. Identity card of Neves Corvo. Experimental memory and the treatment the ore is subjected to. This signature is Volcanogenic Massive Sulphide (VMS) deposits in order a satisfactory differentiation between the nine deposits. A loss refers to a characteristic of the mineral processing rigorously established only at a given moment of to consider a single metallogenic process. We chose to flow chart using logical criteria to discriminate ore (Machault et al. 2013). observation. In the case of base metals, traceability is the study bulk ores of nine deposits from two different deposits can also be established (Melcher et al. 2008a, b), ability to find, for a given concentrate, the trace of all provinces: the South-Iberian province and the Urals but it requires a hierarchy of the considered parameters or manufacturing stages (mineral processing) and the province. provenance (deposit) of all its components. The traceability of a metal concentrate would be possible to 5 Results determine: (1) the province, the district, the deposit and bulk ore from which it was extracted; (2) the mining Bulk ores of deposits from the South-Iberian and Urals company; (3) the different places where it has been stored; provinces have been characterized. It should be noted (4) the manipulations and the equipment used in its again that the observations and the measured parameters manufacturing; (5) its transportation to its final and therefore the ore comparisons, have been inferred destination; (6) its end-use; (7) its recycling; (8) its only from the samples collected so that the conclusions possible reutilization. are therefore only valid for the set of studied samples. In consequence such a traceability study requires to be 3 Methodology of traceability in the case of updated periodically. Results will be expressed in base metals in Volcanogenic Massive qualitative or semi-quantitative form. The different Sulphide parameters of the identity card (Fig. 2) from bulk ore of each ore deposit allow us to differentiate deposits from a Figure 1 is a flowchart illustrating the methodological single province and also to distinguish different procedure followed in this study. We have selected the provinces. We can evaluate the effect of regional heritage samples we considered as the most representative ones on the mineralogical composition and the chemistry of the according to their texture and mineralogical bulk ore minerals. compositions. Variability within a deposit can be The parameters of the identity card are: the significant. Comparisons are only valid at the time of mineralogical composition in the form of relative sampling. That raises the problem of feasibility. The bulk abundance, the microtextures of target minerals (the ore characterization was conducted using a metallurgical following provides a description as well as a tentative microscope, a scanning electron microscope (SEM) and evolution in time of these microtextures, Fig. 3), the an electron microprobe. These techniques are used to pseudo-paragenetic succession, the chemical compo- Figure 3. A. Framboidal pyrites evolution from Neves Corvo and Tharsis deposits (pictures taken through a metallographic study the textures, mineralogical composition, and microscope) stage 1-framboidal pyrite, stage 2-crusting–fibro-radial structure, stage 3-crusting with chalcopyrite– coprecipitation sition and the distribution of target minerals and when pyrite-chalcopyrite, stage 4-disappearance of spherulites in the inner part, stage 5-cristallization continues– growth of large crystals, chemistry of the minerals. Statistical analyses are then possible, the “memory loss” parameter which is a stage 6-brecciation–deposition of other sulphides; B. Sphalerites associated with pyrite and chalcopyrite from Neves Corvo and Tharsis performed on the individual mineral phases to finally characteristic of mineral processing (Machault et al. bulk ore (pictures taken through a metallographic microscope) stage 1- sphalerite, chalcopyrite, pyrite (micro-crusting), stage 2-the obtain an identity card of each studied ore (Fig. 1). During 2013). pyrire growth, stage 3-microfracturing–filling by sphalerite, stage 4-filling continues, stage 5-chalcopyrite inclusions in sphalerite. The observations, a particular attention has been paid to: the scale shown is valid throughout the figure.

1548 MINERAL RESOURCES IN A SUSTAINABLE WORLD • 13th SGA Biennial Meeting 2015. Proceedings, Volume 4 achieve a good traceability are governed by standards identification of characteristics microfacies, the presence 6 Discussion criteria. At this stage of method development, the and/or national or international control organizations. In of trace minerals and finally the minor elements contained establishment of a hierarchy between the retained the case of mineral resources, traceability consists of in the “target minerals”. The “target minerals” are: (1) 6.1. Appropriateness of the methodological characteristics, valid for all VMS deposits, seems associating a commodity to the mine from which it has Pyrite for its ubiquity in the studied bulk ore deposits approach used premature. However we are able to produce flow charts been extracted. For base metals, the bulk ores bear which allows to compare bulk ores from different mines; for each parameter showing their discriminative or mineralogical differences, which may provide (2) Sphalerite, which can incorporate into its structure a We have established an original traceability method for satisfactory features (Fig. 4). characteristics to track the bulk ore. These characteristics large number of potentially valuable elements (Ge, Ag, In, base metals. This traceability method can be used to may “survive” during mineral processing, so that we can Ga) or non-valuable elements (Fe, Cd, Hg, Mn, Sb); (3) obtain a comprehensive identity card of the deposits. find “footprints” of bulk ore in the concentrate. Hence Chalcopyrite that is repeatedly found associated with Mineral chemistry is considered to be the most promising metal ore traceability implies that, in the ideal case, for pyrite and sphalerite. tool for provenance analyses. The comparative results each province and also for each deposit, valuable mineral obtained from the statistical tests (Kolmogorov Smirnov have an unique signature. The characteristics that can be and Colin White) are roughly similar, regardless of the observed in concentrated at grain-scale (mineralogical elements or considered target minerals. Therefore the composition, chemical composition of the phases, Colin White test appears to be the most effective test to microtexture) will depend on (1) the process of formation compare the minor elements content in ore, since (1) it of the mineralization and its post-deposit history (type of necessitates fewer individual data; (2) it is not influenced ore deposit) and (2) the local geological setting including by the value of individual data and (3) it is not sensitive the host rocks (regional setting which is sometimes poorly to element distribution heterogeneity. understood). The concentrate is derived not only from natural processes, but also from industrial processes, 6.2. Utilisation of discriminative parameters for which must be taken into account. In addition to the ore traceability processing difficulties like mixing of bulk ores This study contributes to the establishment of various (Kvarnström and Oghazi 2008) we cannot exclude Figure 1. Organization chart of the method used for variations over time in the operation of a given establishing identity cards parameters that differ from a deposit or a province to mineralurgical plant. Finally, within a given mine, the another. Some of these parameters are discriminative but nature of the bulk ore may vary over time as the 4 Presentation of the metallogenic context a single characteristic is generally not enough to obtain a exploitation of the site progresses. Hence, the signature of of the two studied provinces successful discrimination of all the studied deposits. It is therefore necessary to combine parameters, as provided in the concentrate depends on the characteristics of useful the ore identity card to get a satisfactory result. In our minerals, the type of deposit, the metallogenic province We limit this study to a single type of deposit: case, there is not any unique parameter that could provide Figure 2. Identity card of Neves Corvo. Experimental memory and the treatment the ore is subjected to. This signature is Volcanogenic Massive Sulphide (VMS) deposits in order a satisfactory differentiation between the nine deposits. A loss refers to a characteristic of the mineral processing rigorously established only at a given moment of to consider a single metallogenic process. We chose to flow chart using logical criteria to discriminate ore (Machault et al. 2013). observation. In the case of base metals, traceability is the study bulk ores of nine deposits from two different deposits can also be established (Melcher et al. 2008a, b), ability to find, for a given concentrate, the trace of all provinces: the South-Iberian province and the Urals but it requires a hierarchy of the considered parameters or manufacturing stages (mineral processing) and the province. provenance (deposit) of all its components. The traceability of a metal concentrate would be possible to 5 Results determine: (1) the province, the district, the deposit and bulk ore from which it was extracted; (2) the mining Bulk ores of deposits from the South-Iberian and Urals company; (3) the different places where it has been stored; provinces have been characterized. It should be noted (4) the manipulations and the equipment used in its again that the observations and the measured parameters manufacturing; (5) its transportation to its final and therefore the ore comparisons, have been inferred destination; (6) its end-use; (7) its recycling; (8) its only from the samples collected so that the conclusions possible reutilization. are therefore only valid for the set of studied samples. In consequence such a traceability study requires to be 3 Methodology of traceability in the case of updated periodically. Results will be expressed in base metals in Volcanogenic Massive qualitative or semi-quantitative form. The different Sulphide parameters of the identity card (Fig. 2) from bulk ore of each ore deposit allow us to differentiate deposits from a Figure 1 is a flowchart illustrating the methodological single province and also to distinguish different procedure followed in this study. We have selected the provinces. We can evaluate the effect of regional heritage samples we considered as the most representative ones on the mineralogical composition and the chemistry of the according to their texture and mineralogical bulk ore minerals. compositions. Variability within a deposit can be The parameters of the identity card are: the significant. Comparisons are only valid at the time of mineralogical composition in the form of relative sampling. That raises the problem of feasibility. The bulk abundance, the microtextures of target minerals (the ore characterization was conducted using a metallurgical following provides a description as well as a tentative microscope, a scanning electron microscope (SEM) and evolution in time of these microtextures, Fig. 3), the an electron microprobe. These techniques are used to pseudo-paragenetic succession, the chemical compo- Figure 3. A. Framboidal pyrites evolution from Neves Corvo and Tharsis deposits (pictures taken through a metallographic study the textures, mineralogical composition, and microscope) stage 1-framboidal pyrite, stage 2-crusting–fibro-radial structure, stage 3-crusting with chalcopyrite– coprecipitation sition and the distribution of target minerals and when pyrite-chalcopyrite, stage 4-disappearance of spherulites in the inner part, stage 5-cristallization continues– growth of large crystals, chemistry of the minerals. Statistical analyses are then possible, the “memory loss” parameter which is a stage 6-brecciation–deposition of other sulphides; B. Sphalerites associated with pyrite and chalcopyrite from Neves Corvo and Tharsis performed on the individual mineral phases to finally characteristic of mineral processing (Machault et al. bulk ore (pictures taken through a metallographic microscope) stage 1- sphalerite, chalcopyrite, pyrite (micro-crusting), stage 2-the obtain an identity card of each studied ore (Fig. 1). During 2013). pyrire growth, stage 3-microfracturing–filling by sphalerite, stage 4-filling continues, stage 5-chalcopyrite inclusions in sphalerite. The observations, a particular attention has been paid to: the scale shown is valid throughout the figure.

Sustainable mining and environmental issues 1549 References Science Outreach and Mining Heritage: Drivers to the Gäbler HE, Melcher F, Graupner T, Bahr A, Sitnikova M, Henjes- Kunst F, Oberthür T, Brätz H, Gerdes A (2011) Speeding up the Rehabilitation of the Mining Village of Lousal, Portugal analytical workflow for coltan fingerprinting by an integrated mineral liberation analysis/LA-ICP-MS approach. Geostand Geoanal Res 35:431-448 Jorge MRS Relvas, Álvaro MM Pinto Gäbler HE, Rehder S, Bahr A, Melcher F, Goldmann S (2013) IDL - Associate Laboratory, University of Lisbon, Faculty of Science, Lisbon, Portugal Cassiterite fingerprinting by LA-ICP-MS. R Soc Chem J Anal [email protected] At Spectrom 28:1247-1255 Giuliani G, France-Lanord C, Coget P, Schwarz D, Cheilletz A, Andreia Mendonça, Carla Malha, Fernanda Albuquerque, Lara Alegre, Mafalda Abrunhosa, Márcia Pinheiro, Branquet Y, Giard D, Pavel A, Martin-Izard A, Piat DH (1998a) Margarida Oliveira, Marina Alves, Miguel Ferreira, Ricardo Rufino, Rute Rolão, Sérgio Pratas, Tânia Ferreira Oxygen isotope systematic of emerald: relevance for its origin Centro Ciência Viva do Lousal – MINA DE CIÊNCIA, Lousal, Grândola, Portugal and geological significance. Miner Deposita 33:513-519

Giuliani G, France-Lanord C, Coget P, Schwarz D, Notary F, Figure 4. Tree parameters: A. microtextures to differentiate Carlos Fernandes deposits; B. mineralogical composition. Deposits are: NC: Cheilletz A, Chaussidon M, Giard D, Piat D, Bariand P (1998b) Vers une carte d'identité isotopique 18O/16O des émeraudes Câmara Municipal de Grândola, Grândola, Portugal Neves Corvo, THA: Tharsis, A: Alexandrinka, SB: Sibay, D: naturelles et synthétiques. Association française de Dergamish, YK: Yaman Kasy, S: Safyanovka, I: Ivanovka, M: gemmologie. L'émeraude, connaissances actuelles et João MX Matos Mauk. prospectives, pp 55-70 LNEG - Laboratório Nacional de Energia e Geologia, Beja, Portugal Giuliani G, Fallick AE, Garnier V, France-Lanord C, Ohnenstetter 7. Conclusions D, Schwarz D (2005) Oxygen isotope composition as a tracer for the origins of rubies and sapphires. Geology 33:249-252 Abstract. The Lousal deposit was mined continuously environmental obligations were imposed by law and This study has contributed to: (1) establish nine ore Herrington RJ, Smith M, Maslennikov V, Belogub E, Armstrong R between 1900 and 1988, exploiting pyrite for sulphur. mines were simply boarded up and abandoned. However, identity cards for two metallogenic provinces: Neves (2002) A short review of Paleozoic hydrothermal magnetite This mining village is currently an international example it is currently accepted that mine closure requires the iron-oxide deposits of the south and central Urals and their Corvo and Tharsis in South Iberian province; of success in socio-economic, environmental and mining return of land to a viable post-mining use, and that the geological setting. In: Porter, T.M. (Ed.), Hydrothermal iron heritage rehabilitation. The program resulted from the Alexandrinka, Dergamish, Yaman Kasy, Safyanovka, socio-economic impacts of the closure must be assessed oxide copper–gold and related deposits: a global perspective, joint efforts of the local municipality - Grândola - and the Ivanovka, Mauk and Sibay in the Urals province; (2) vol. 2. PGC Publishing, South Australia, pp243-253 mine owner company – Sapec, SA. It was responsible for and managed. Therefore, the Lousal mining village is discriminate the bulk ores from deposits in a given Kvarntröm B, Oghazi P (2008) Methods for traceability in the restoration of the mineshafts and conversion of the being rehabilitated not only as a geological and mining continuous processes experience from an iron ore refinement province and the bulk ores between distinct provinces; (3) old power plant into a mining museum. The main heritage site, but also as a centre for education for process. Miner Eng 21:720-730 reveal pyrite as a characteristic microtexture parameter warehouse was transformed into a regional restaurant, science and technology and a destination for tourism of Machault J, Barbanson L, Augé T, Bailly L, Felicio A (2013) for performing bulk ore traceability. This parameter is not Memory loss duringmineral processing: application to base the administration house was converted into a rural hotel, nature, culture and patrimony. Here, we address the main influenced by the age of the deposit, the tectonics zone metals traceability. Miner Eng 46-47:112-118 and the mine offices into a handicraft centre. A components of this successful rehabilitation program. where the deposit is located and the nature of the rocks Machault J, Barbanson L, Augé T, Bailly L, Orgeval JJ (2014) rehabilitation plan directed to reclaim the contaminated hosting the deposit. Mineralogical and microtextural parameters in metals ores areas was developed. Some other mining facilities gave 2 The past rise to a Science Centre that promotes non-formal, This method forms the basis of a necessary protocol to traceability studies. Ore Geol Rev 63:307-327 science outreach educational activities, which represent establish base metals ore traceability. For this, to achieve Melcher F, Sitnikova MA, Graupner T, Martin N, Oberthür T, Henjes-Kunst F, Gäbler E, Gerdes A, Brätz H, Davis DW, a very strong attractor for public that definitely changed The discovery of the Lousal deposit took place in 1882 the monitoring of ore parameters, it is necessary Dewaele S (2008a) Fingerprinting of conflict minerals: the daily life scenario of Lousal. The strong commitments by a local farmer. However, the area shows several signs throughout the life of a mine, including costs for analyses columbite–tantalite (“coltan”) ores. SGA News 23:6-14 of many institutions, with emphasis on the University of of mining activity since the Bronze Age (ca. 3300 BC), and competent operators. Such studies will also contribute Melcher F, Graupner T, Henjes-Kunst F, Oberthür T, Sitnikova M, Lisbon, have raised very high the scientific standards of with particular emphasis on constructions probably built to increase the amount of data usuable for understanding Gäbler E, Gerdes A, Brätz H, Davis D, Dewaele S (2008b) the whole initiative. for defense as well as for ore storage. Between 1900 and the genesis of an ore deposit and the metallogenic Analytical fingerprint of columbite–tantalite (coltan) 1934, the exploitation rights were property of several mineralisation in pegmatites—focus on Africa. Ninthe Keywords. Lousal Mine, Mine rehabilitation, RELOUSAL processes involved. The deposits are unpredictable by International Congress for Applied Mineralogy Brisbane, QLD, individual persons and companies. In 1936, the Belgian nature. It is difficult to take into account the internal program, Iberian Pyrite Belt corporation Société Anonyme Mines et Industries S.A., 8-10 September variability of the deposit. This leads to the necessity to Melcher F, Graupner T, Gäbler HE, Sitnikova M, Henjes-Kunst F, which preceded SAPEC, became the owner of the ensure a continuous watch, which also provides a better Oberthür T, Gerbes A, Dewaele S (2015) Tantalum-(niobium- 1 Introduction Lousal mine (Rodrigues 2005). SAPEC still owns the

understanding of deposits in particular on valuable low tin) mineralisation in African pegmatites and rare metal mine despite the shut down of the operation in 1988. The The Lousal mine was an important massive sulphide grade elements. The industrial and academic communities granites: constraints from Ta-Nb oxide mineralogy, geo- urban structure of the Lousal village is centred on the chemistry and U-Pb geochronology. Ore Geol Rev 64, 667-719 deposit of the Iberian Pyrite Belt located in its NW will also benefit from traceability monitoring, which will buildings related to the mining activity – headframes, Oghazi P, Palsson B, Tano K (2009) Applying traceability to sector, in an area limited to the N, E and S by the provide regular quantitative data throughout mineral workshops, stores and laboratories –, which spread out grinding circuits by using Particle Texture Analysis (PTA). Tertiary sediments of the Alvalade basin (Schermerhorn processing potentially improving its efficiency. Finally, Minerals Engineering 22:710-718 over the entire mining perimeter. Besides the mining et al. 1987; Matos and Oliveira 2003). The deposit the establishment of traceability methods based on minor Oliveira JV (1990) South Portuguese Zone. In : Dallmeyer RD, buildings, there are two other groups of structures in the consists of several ore lenses that are lined up along 1.5 element contents will have an effect on mineral resource Garcia EM, Pre-Mesozoic geology of Iberia. Springer pp334- area: the social support buildings – medical ward, 347 km length in strike (Strauss 1970). It consisted of about management especially for strategic (critical and school, church and market – and the housing buildings, Savu-Krohn C, Randtitsch G, Auer P, Melcher F, Graupner T (2011) 50 Mt of ore at 1.4% zinc, 0.8% lead and 0.7% copper valuable) elements which are sensitive to market including accommodation for the miners and for the Geochemical fingerprinting of coltan ores by machine learning (Strauss 1970). The massive sulphide mineralization fluctuations. technical personnel, and the administration building. In on uneven datasets. Nat Resour Res 20 :177-191 occurs in close dependence to felsic volcanic centres, 1958, Frédéric Velge, son of Antoine Velge, the main where intense ore-forming hydrothermal activity led to Acknowledgements holder of Société Anonyme Mines et Industries, SA, extensive chloritic/sericitic alteration and stockwork became director of the Lousal Mine and opened an mineralization (Fernandes 2011). The mine was active The authors are grateful for the financial support by epoch of great expansion for the mine. With the help of for sulphur between 1900 and 1988 and part of its convention n° 200800034766 of the ‘‘Région Centre’’ the on-site geologist Günter Strauss, he modernized the surface infrastructures are rather well preserved. (France). Furthermore, we also thank Alexandre Felicio management and introduced new methods of mechanised In the past, the safety, environmental and social risks of the SOMINCOR company for Neves Corvo samples mining production. The closure of the Lousal Mine, in arising from badly conducted mine closures resulted in and Valery Maslennikov for Urals samples and for all 1988, followed the unsustainability of sulphur severe distress for communities due to environmental, their complementary information provided. production out of pyrite. social and economic collapse, as in most cases very little

1550 MINERAL RESOURCES IN A SUSTAINABLE WORLD • 13th SGA Biennial Meeting 2015. Proceedings, Volume 4