The concept of gamification is being increasingly explored and applied to offer new teaching or training tools to teachers, students or employees. The field of geology and geometallurgy wasn’t particularly discussed in the topic of gamification. With the objective of creating a synthetic geometallurgical database and a game structure for a gamified simulation of a metal mine, the eastern part of the Malmberget deposit in Sweden was simplified and modelled.The geological model was obtained with assumptions of continuity and proximity, and the lack of data was reconciled using targeted randomization and regular statistics to achieve a smoother and realistic result. A rule book was created to establish the framework that a geometallurgy game should follow,using a slightly adapted version of the Desing thinking framework by the Nielsen group, which consists of elaborating ideas and concepts, implementing them and testing the results before integrating feedbacks to the creation of future elements. The accent was put on obtaining an interactive experience where the player can try various things with a reasonable difficulty, and an accessibility to feedbacks.The purpose of this project is to elaborate a mining simulation game, that could be a valuable tool in the understanding of the interdisciplinary concept of geometallurgy, as well as raising the awareness about sustainable development and how mining can be a part of it. The starting point of this project is another attempt at gamifying geometallurgy by P. Lamberg. The simulation of mineral processing was done using the HSC Sim utilizing 8 different flowsheets that were designed to offer a variety and enable strategic choices. The events occurring at a real mine and beneficiation plant were translated into simple rules. The outcome is a realistic geological and processing model, which through the addition of mining, economics and market strategy, becomes a comprehensive geometallurgy database.

This paper presents the results of a mineralogical and metallurgical study of supergene ores at the Mike Cu-Au(-Zn) deposit on the Carlin trend of Nevada, USA, currently held by Newmont Gold Corporation. With a metal endowment totaling >8.5 M oz. Au, 1027 M lbs. Cu, and 809 M lbs. Zn, Mike is one of the largest deposits on the Carlin trend, but it is currently uneconomic to develop. It contains an unusual and complicated suite of metals and ore minerals. This study was undertaken as a first step to investigate process options for recovering both its Cu and Au by 1) comparing the metal recoveries achieved from the supergene ores by six different lixiviants, and 2) identifying which minerals failed to dissolve in each lixiviant. The reagents selected were sulfuric, sulfurous, and methanesulfonic acids, to recover Cu, and cyanide, thiourea, and glycine, to recover Cu and Au. QEMSCAN and SEM study of six samples of different ore types and grades indicate that the Au occurs as varieties of native gold, including auricupride and electrum. Major Cu minerals are native Cu, cuprite, malachite, chrysocolla, and conichalcite (Ca-Cu arsenate), with locally significant Cu in jarosite and goethite. Gangue mineralogy is dominated by quartz, sericite, chlorite, alunite, smectite and kaolinite, K-feldspar, jarosite, and iron oxides. Bottle roll testing indicates that no single-step leaching process is likely to provide economic recovery of both Cu and Au. Sulfuric and methanesulfonic acid both recovered > 70% of the Cu except from the samples dominated by conichalcite, which was not leached effectively by any of the reagents tested. Only cyanide and thiourea recovered significant Au. Reagent consumption for cyanide, sulfuric acid, and methanesulfonic acid was generally within acceptable levels. Glycine and sulfurous acid are both uneconomic based on low recovery. Further work will focus on developing an economic process in two steps. Mineralogical study of QEMSCAN residue indicates that the non-leaching ore minerals are conichalcite and Cu-bearing Fe oxides. In addition, native Cu and cuprite do not leach well in glycine and chrysocolla does not leach well in thiourea or cyanide. Other observed mineralogical changes include the total loss of dolomite and partial loss of alunite and iron oxide from all samples, with apparent gains in jarosite.

A geometallurgical model is the combination of a spatial model representing an ore deposit and a process model representing the comminution and concentration steps in beneficiation. The process model itself usually consists of several unit models. Each of these unit models operates at a given level of detail in material characterization - from bulk chemical elements, elements by size, bulk minerals and minerals by size to the liberation level that introduces particles as the basic entity for simulation (Paper 1). In current state-of-the-art process simulation, few unit models are defined at the particle level because these models are complex to design at a more fundamental level of detail, liberation data is hard to measure accurately and large computational power is required to process the many particles in a flow sheet. Computational cost is a consequence of the intrinsic complexity of the unit models. Mineral liberation data depends on the quality of the sampling and the polishing, the settings and stability of the instrument and the processing of the data. This study introduces new tools to simulate a population of mineral particles based on intrinsic characteristics of the feed ore. Features are extracted at the meso-textural level (drill cores) (Paper 2), put in relation to their micro-textures before breakage and after breakage (Paper 3). The result is a population of mineral particles stored in a file format compatible to import into process simulation software. The results show that the approach is relevant and can be generalized towards new characterization methods. The theory of image representation, analysis and ore texture simulation is briefly introduced and linked to 1-point, 2-point, and multiple-point methods from spatial statistics. A breakage mechanism is presented as a cellular automaton. Experimental data and examples are taken from a copper-gold deposit with a chalcopyrite flotation circuit, an iron ore deposit with a magnetic separation process. This study is covering a part of a larger research program, PREP (Primary resource efficiency by enhanced prediction). / PREP

Previous studies have suggested that Davis tube (DT) experiment can used to study wet low intensitymagnetic separation (WLIMS) for magnetic iron ores. But DT process has never been used to mapWLIMS process, specifically in a geometallurgical framework. This thesis work is a step towardsfulfilling this gap by studying the Davis tube experiment performed on 13 different samples fromLeveäniemi iron ore deposit. The methodology adapted to map WLIMS concentrate quality includesstudy and analysis of feed, DT and WLIMS. Analyses were made using experimental data, processingdata using some analytical tools, some data-processing tools and post processing tools. For coveringthe geometallurgical aspect the analysis was done for both elements and minerals. The results fromthis study has reviled that DT can be used to predict WLIMS concentrate quality to an acceptablelevel of confidence. Furthermore, results show that a combination of DT and WLIMS informationproduce very accurate and highly reliable models for predicting and mapping WLIMS concentratequality. This work serves as the first step towards studying an unexplored field pertaining to magneticiron ore concentrate and has opened door to possible future work that could take this work a stepfurther. Supplementing this study with more data from different sample is required not only tovalidate the model but also to make it better. A better modal mineralogy of the samples is needed tounlock the full potentials of mineralogical modelling approach used in this work. / <p>I am a graduate from the of Erasmus Mundus masters in Georesource Engineering, 2017.</p> / Primary Resource Efficiency by Enhanced Prediction (PREP)

The demands for efficient utilization of ore bodies and proper risk management in the mining industry have resulted in a new cross-disciplinary subject called geometallurgy. Geometallurgy connects geological, mineral processing and subsequent downstream processing information together to provide a comprehensive model to be used in production planning and management. A geometallurgical program is an industrial application of geometallurgy. Various approaches that are employed in geometallurgical programs include the traditional way, which uses chemical elements, the proxy method, which applies small-scale tests, and the mineralogical approach using mineralogy or the combination of those. The mineralogical approach provides the most comprehensive and versatile way to treat geometallurgical data. Therefore it was selected as a basis for this study. For the mineralogical approach, quantitative mineralogical information is needed both for the deposit and the process. The geological model must describe the minerals present, give their chemical composition, report their mass proportions (modal composition) in the ore body and describe the ore texture. The process model must be capable of using mineralogical information provided by the geological model to forecast the metallurgical performance of different geological volumes and periods. A literature survey showed that areas, where more development is needed for using the mineralogical approach, are: 1) quick and inexpensive techniques for reliable modal analysis of the ore samples; 2) ore textural characterization of the ore to forecast the liberation distribution of the ore when crushed and ground; 3) unit operation models based on particle properties (at mineral liberation level) and 4) a system capable of handling all this information and transferring it to production model. This study focuses on developing tools in these areas. A number of methods for obtaining mineral grades were evaluated with a focus on geometallurgical applicability, precision, and trueness. A new technique developed called combined method uses both quantitative X-ray powder diffraction with Rietveld refinement and the Element-to-Mineral Conversion method. The method not only delivers the required turnover for geometallurgy but also overcomes the shortcomings if X-ray powder diffraction or Element-to-Mineral Conversion were used alone. Characterization of ore texture before and after breakage provides valuable insights about the fracture pattern in comminution, the population of particles for specific ore texture and their relation to parent ore texture. In the context of the mineralogical approach to geometallurgy, predicting the particle population from ore texture is a critical step to establish an interface between geology and mineral processing. A new method called Association Indicator Matrix developed to assess breakage pattern of ore texture and analyze mineral association. The results of ore texture and particle analysis were used to generate particle population from ore texture by applying particle size distribution and breakage frequencies. The outcome matches well with experimental data specifically for magnetite ore texture. In geometallurgy, process models can be classified based on in which level the ore, i.e. the feed stream to the processing plant and each unit operation, is defined and what information subsequent streams carry. The most comprehensive level of mineral processing models is the particle-based one which includes practically all necessary information on streams for modeling unit operations. Within this study, a particle-based unit operation model was built for wet low-intensity magnetic separation, and existing size classification and grinding models were evaluated to be used in particle level. A property-based model of magnetic beneficiation plant was created based on one of the LKAB operating plants in mineral and particle level and the results were compared. Two different feeds to the plant were used. The results revealed that in the particle level, the process model is more sensitive to changes in feed property than any other levels. Particle level is more capable for process optimization for different geometallurgical domains.

The Nkout (Cameroon) and Putu (Liberia) oxide facies iron ore deposits comprise fresh magnetite banded iron formation (BIF) at depth, which weathers towards the surface, forming high grade martite–goethite ores. This study aimed to improve the mineralogical understanding of these deposits in order to predict their metallurgical responses. It concentrated on developing the QEMSCAN® technique and testing its application to these ore types, but also used a variety of other analysis methods. The QEMSCAN® species identification protocol was developed to include three goethite entries: goethite/limonite, phosphorus-bearing and aluminium-bearing goethite. QEMSCAN® was also used to distinguish between the iron oxides using their backscattered electron signals. To test the correlation between the mineralogy and metallurgical characteristics, magnetic separations were carried out. The samples were divided into 4 main groups based on their whole rock Fe content, determined by XRF analysis, and their degree of weathering: enriched material, weathered magnetite itabirite, transitional magnetite itabirite and magnetite itabirite. Quartz and Al oxide and hydroxide minerals such as gibbsite are the major gangue minerals in the magnetite BIF and martite–goethite ores respectively. From the QEMSCAN® analysis it was concluded that the iron oxides are closely associated and liberation of them individually is poor. Liberation increases when they are grouped together as iron oxide. Chamosite concentrations > 6 wt. % significantly lower liberation of the iron oxides. From the metallurgical testing, it was concluded that iron oxide modal mineralogy gives an indication of iron recovery but other QEMSCAN® data such as mineral association and liberation could be important especially if the iron oxide minerals are not liberated. Grain size and instrument characteristics also affect recovery of iron minerals. There is no evidence to show that there is any structural control on the BIF mineralisation at Nkout because metamorphism has significantly affected the lithological characteristics. The BIF mineralised zones occur as stacks with no particular stratigraphic relationship. Alteration and stratigraphy are the main controls on the martite–goethite ores. These results are applicable to most other BIFs so that as direct shipping ores are exhausted, the approach used here can help to develop the lower grade portions of the deposits.

The Björkdal gold deposit is located in the eastern part of the Skellefte district, northern Sweden. Twenty thin sections from four production areas in the open pit and four drifts from the underground mine were analysed for mineral association and grain size distribution of gold. In addition, the texture of gold was investigated in order to find out how that affects the recovery of gold. The overall gold grain size distribution shows an interval from very fine-grained (2 μm) to coarse grained(856 μm) while the overall median size is 7 μm. Gold from the Quartz Mountain production area displays the smallest median size of 4 μm, whereas gold from the sampled drifts at 340m- and 385m- level has the largest median size of 14 μm. Gold at grain boundary is the dominant textural mode of gold from all sampled locations and varies from 62% to 92%. This is followed by intergrown which ranges between 8% and 29%. Of the sulfides, pyrite, chalcopyrite and pyrrhotite are the most common. Galena and was also present in the samples. Gold is significantly and positively correlated with tellurium (Appendix 10.1.1), and weakly positive correlated to silver and mercury. Gold show a close association to bismuth-tellurides in the samples. Apart from native gold, which is the dominant mineral phase of gold, two additional gold-bearing tellurium minerals were detected with SEM-EDS, a Au-Te-mineral and a Ag-Au-Te-mineral. One additional bismuth-telluride mineral aside from the most commonly occurring tsumoite (BiTe) was also detected with SEM, with a elemental composition of Bi-Te-S. Liberated gold in the tailings was optically identified in two thick sections, TB1-02feb-1 and TB1-07feb-1 (Fig. 32A and B), where the flotation circuit failed to float the free gold. One grain of gold was also identified intergrown with bismuth-telluride as an inclusion in silicate (Fig. 33), where the flotation properties of the larger silicate grain likely dominated in the flotation process. This thesis highlights the importance of further quantitative analysis utilizing SEM/QEMSCAN/MLA to retrieve representative mineralogical data to benefit the mineral processing of the ore from the active mine. Keywords: Björkdal gold deposit, gold, gold-telluride, SEM, mineral association, grain size,geometallurgy.

Geometallurgy describes a holistic approach to mining (integrating geological, metallurgical, geotechnical, environmental, and more parameters) with the goal to improve the efficiency and sustainability of a mining operation. The potential of systematic optical petrography in a geometallurgical context was investigated in this study, as well as how petrography may be useful across disciplines in several blocks of the mining value chain. In a case study, twelve boulder samples (non-mineralized and mineralized) from the Rajapalot exploration property in Finland were characterized by detailed optical microscopy and scanning electron microscopy (SEM) with the aim to delineate the origin of the respective boulders. This allowed to demonstrate some benefits and challenges of systematic optical petrography in the mining value chain and geometallurgical programs. The study was performed through the geology department at Mitta AB in Luleå, Sweden, using rock samples supplied by Mawson Gold Ltd, Finland. The Rajapalot Au-Co property lies a few km east of the Rompas Au-U property, both owned by Mawson Gold Ltd and located in the Paleoproterozoic Peräpohja belt in northwest Finland. When determining the boulders’ origin, geochemical gradients of the Peräpohja belt lithostratigraphy; oxidized sodic rocks in the Kivalo group and reduced potassic rocks in the Paakkola group were crucial factors. The mineralization style of the Rompas Au-U association and the Rajapalot Au-Co association (including the “Palokas” Fe-Mg type and the “Rumajärvi” K-Fe type) were further crucial to classify the mineralized boulders. Results show that the rock types (and suggested origin) vary between boulder samples. Most samples are presumed to originate from the Paakkola group, one sample from the Kivalo group, and a few samples are inconclusive. Furthermore, the samples impact on the mining value chain was discussed based on the results of the petrographic analysis. A method description for a more systematic way of examining rock material is presented, including for example quantitative parameters such asmodal mineralogy and grain size distribution. However, the applicability of this method description needs further study.

Aitik is a large copper porphyry type deposit located in northern Sweden, currently exploited at an annual rate of approximately 45Mt. The ore's exceptionally low head grade of 0.22 % Cu and varying degrees of hardness across the entire deposit pose challenges to the two fully autogenous grinding lines, each of which comprises a 22.5 MW primary autogenous mill in series with a pebble mill. The variability in ore grindability frequently leads to fluctuations in mill throughput.  Within the framework of a geometallurgical approach, the present study investigated the relationships between ore grindability and modal mineralogy. For this purpose, drill core samples from different lithologies were subjected to Boliden AB's in-house grindability tests. This laboratory-scale autogenous grinding test generates a grindability index Ks mainly related to abrasion breakage, which is a significant breakage mechanism within autogenous mills. The test results suggested divergent degrees of grindability within and across the selected rock types. Furthermore, subsequent sieve analyses identified a relationship between the grindability index, PSD, and the proportions of fines generated by abrasive grinding. A combination of scanning electron microscopy, X-ray powder diffraction, and X-ray fluorescence analyses was performed for the grinding products and bulk mineral samples. The resulting mineralogical and elemental properties were correlated to the parameters from the grindability tests. It was shown that the main mineral phases, such as plagioclase, quartz, and micas, correlate well with the grindability indices. Similar correlations were found regarding the sample's chemical composition, attributable to the main mineral phases. Derived from the previous findings, two exemplary linear empirical models for the calculation of grindability based on either mineral contents or chemical composition were presented. Careful examination of the mineralogical data revealed that the prevalent abrasion breakage mechanism leads to constant and continuous removal of mineral particles from the sample's surface. No indications for a preferential abrasion of any mineral phases were found.  A further inverse correlation between the sample's calculated average weighted Mohs hardness based on modal mineralogy and the grindability index Ks was established. Hence, it was proposed that a higher Mohs hardness results in a finer grinding product, oppositional to the Ks-values. Since Ks can be interpreted as a measure of abrasiveness, it can be stated that abrasiveness decreases with an increasing average sample hardness and vice versa.  Moreover, mineral liberation information provided by scanning electron microscopy was associated with the parameters mentioned earlier. It was determined that different degrees of mineral liberation were reached within specific particle size classes. The identified relationships between grindability, modal mineralogy, and element grades may help Boliden develop a predictive throughput model for Aitik to be integrated into the mine's block model. Based on this information, a strategy for smart blending could be developed, where run of mine material from ore blocks of varying grindabilities could be blended to attain the target plant throughput.

O Grupo Vazante hospeda o maior depósito de Zn não-sulfetado, hipógeno, conhecido mundialmente, Vazante (>60 Mton @ 20% Zn), que ainda possui concentrações de Pb e Ag. A Mina de Vazante (VZT) e sua continuidade, a Mina de Extremo Norte (EN), são subdivididas em cinco domínios geo-mineralógicos, sendo três deles pertencentes à VZT: Lumiadeira 1 (LUM1); Lumiadeira 2 (LUM2); Sucuri (SUC) e dois à EN: Extremo Norte 1 (EN1) e Extremo Norte (EN2). Estudos de campo, amostragem sistemática, análises petrográficas e com uso de microscopia eletrônica de varredura, incluindo mineralogia automatizada por Mineral Liberation Analyzer, e microssonda eletrônica, e litoquímicas foram empregadas objetivando caracterizar detalhadamente cada domínio, relacionar aspectos geológicos e mineralógicos e apontar possíveis fatores responsáveis por mudanças na qualidade do minério frente aos processos de beneficiamento. Os corpos de minério de Zn não-sulfetado nas minas VZT e EN são compostos essencialmente por willemita (Zn2SiO4), possuem formas anastomosadas e são hospedados por brechas dolomíticas e subordidamente por rochas metapelíticas e metabásicas e brechas hematíticas. Corpos restritos ricos em sulfetos ocorrem, principalmente, imbricados em corpos de minério willemítico ou como veios e vênulas. Os cristais de willemita apresentam texturas de preenchimento, como coloforme e fibro-radiada (tipo I), de reequilíbrio, como granoblástica (tipo II), ou são finamente granulares e preenchem fissuras tardias (tipo III). Desse modo, registram complexa sequência de processos e condições para a geração do minério de Zn não-sulfetado. Zinco, Fe, C, Ca, SiO2, e Mg são os principais componentes químicos do minério. Na mina EN, o teor de Fe (<26,7%) no minério é, em média, mais elevado quando comparado à mina VZT, presente principalmente na forma de hematita. Chumbo e Ag, co-produtos da explotação de Zn, são principalmente encontrados na mina VZT, nos domínios LUM1 e SUC onde são concentrados em corpos ricos em sulfetos. Elementos terrígenos, tais como Al, K, Rb, Sc, Co, Th e La são positivamente anômalos no domínio LUM2 indicando maior presença de metapelitos no setor sul da mina VZT. Quando associado à metapelito, o minério willemítico pode conter até 15% de Zn-talco, podendo assim refletir em menores recuperações de Zn. Quando hospedado por rochas metabásicas, o principal mineral de zinco pode ser franklinita (<25%), mineral deletério para o processamento de minério. Caso hospedado por brechas hematíticas, característica do domínio EN2, a willemita apresenta-se comumente cominuída e os conteúdos de Fe e hematita podem ser limitantes para o beneficiamento. Em síntese, os resultados desse estudo mostram que cada domínio geo-mineralógico apresenta características específicas. Mostrou-se que espessura, formato e profundidade dos corpos, variação da natureza das rochas encaixantes e substituições minerais afetam diretamente a mineralogia e a qualidade do minério de Zn. Tais fatores refletem processos geológicos e características do ambiente formacional do depósito que podem ser restritos ou mais frequentes em determinado domínio, refletindo assinaturas específicas para o minério estudado, que podem ser espacializadas e monitoradas integrando um modelo geometalúrgico. / The Vazante Group hosts the major hypogene, nonsulfide Zn deposit known worldwide (e.g., Vazante; >60 Mton @ 20% Zn), which also contains Pb and Ag concentrations. The Vazante Mine (VZT) and its continuity, the North Extension Mine (EN), are subdivided into five geo-mineralogical domains, since three belonging to VZT: Lumiadeira 1 (LUM1); Lumiadeira 2 (LUM2); Sucuri (SUC), and two to EN: North Extension 1 (EN1); North Extension 2 (EN2). Field studies, systematic sampling, petrography, scanning electronic microscopy, automated mineralogy via Mineral Liberation Analyzer, and lithochemical analyses were carried out aiming to characterize each domain in detail, connect their geological and mineralogical aspects, and point to possible features responsible for changes on ore quality during ore beneficiation. The nonsulfide Zn orebodies at VZT and EN are anastomosed, composed of willemite (Zn2SiO4), and hosted by dolomite breccias and subordinately by metapelite, metabasic rocks, and hematite breccias. Minor sulfide-rich orebodies occur mainly imbricated within willemite orebodies or as veins and veinlets. The willemite crystals show infilling textures, such as colloform and fibrous-radiated (type I), reequilibrium texture, such as granoblastic (type II), or fine-grained textures, when controlled by late fissures (type III). Thus, willemite registers a complex sequence of processes and conditions responsible for the nonsulfide Zn ore generation. Zinc, Fe, C, Ca, SiO2, and Mg are the main chemical compounds of the ore. At EN, the Fe (<26.7%) and hematite contents in the ore are, on average, higher than those of VZT. Lead and Ag, co-products of Zn exploitation, are chiefly found at VZT, in the LUM1 and SUC domains, concentrated in sulfide-rich bodies. Terrigenous elements, such as Al, K, Rb, Sc, Co, Th, and La, are positively anomalous in the LUM2 domain indicating the influence of metapelite host in the south sector of VZT. In this case, willemite ore may contain up to 15% Zn-talc, related to lower Zn recoveries. If the willemite ore is hosted by metabasic rocks, franklinite, a deleterious phase into processing, might be the main Zn-bearing phase (<25%). If hosted by hematite breccias, characteristic of the EN2 domain, willemite is commonly comminuted and the Fe and hematite contents might be a limiting for beneficiation. The results herein presented show that each geo-mineralogical domain exhibits their own characteristics. Ore thickness, format, and depth of bodies, the nature of host rocks, and mineral replacements affect the mineralogy and quality of Zn ore directly. Those factors express geological processes and characteristics of the deposit environment that may be restricted or more frequent at a certain domain, thus creating specific signatures for the analyzed ore, which might be spatialized and monitored integrating a geometallurgical model.