An assessment of tin-skarn resources in the Erzgebirge, Germany, was conducted with the 3-Part Method. For this purpose a Grade-Tonnage Model for this deposit type was established. A literature review produced grade and tonnage data for 23 skarn deposits, of which 9 are in the assessment area. Based on an existing predictive map created with an AI algorithm, seven permissive tracts with a total area of 776 km² were defined. To estimate the number of undiscovered deposits a panel of five experts in the economic geology of the Erzgebirge was assembled. From the expert estimates and the newly developed Grade-Tonnage Model the undiscovered ore and metal tonnages in each permissive tract were evaluated. In four of the seven tracts the probability of the existence of at least one undiscovered deposit is estimated to be greater than 50%, in permissive tract 2 it is even greater than 90%. In each of these tracts, the median assessed undiscovered ore tonnages are several million tons and the tin resources exceed 10,000 tons. For the most perspective tract (Permissive tract 2) the median estimates are 40.6 Million tons of ore with a tin content of 114,000 tons. For tungsten (tonnages calculated as WO3) the numbers are slightly lower. The results verify the high resource potential of tin skarns in the Erzgebirge and can be used to guide future exploration activities to the most economically promising permissive tracts.

Το αντικείμενο της παρούσας διπλωματικής εργασίας είναι η μελέτη, η κατηγοριοποίηση και η ταξινόμηση των ιστολογικών σχέσεων μεταξύ των μεταλλικών ορυκτών. Με την συλλογή πληροφοριών δημιουργήθηκε ουσιαστικά ένας Άτλας Μεταλλικών Ιστών που εμπεριέχει τόσο την θεωρητική προσέγγιση της περιγραφής των κατηγοριών των μεταλλικών ιστών όσο και τη απεικόνιση των ιστολογικών σχέσεων από μακροσκοπικές, μικροσκοπικές φωτογραφίες και δισγράμματα. Ιστός (texture) είναι η αμοιβαία διευθέτηση και σχέση των κρυστάλλων ενός, ή διαφορετικών ορυκτών εντός του χώρου (δηλαδή σε τρείς διαστάσεις). Παρατηρείται με γυμνό μάτι, αλλά κυρίως με το μικροσκόπιο. Οι ιστοί χωρίζονται σε πρωτογενείς και δευτερογενείς. Οι πρωτογενείς ιστοί προέρχονται από καθίζηση των κρυστάλλων από τήγματα και από καθίζηση από υδροθερμικά διαλύματα. Οι δευτερογενείς ιστοί παράγονται από ψύξη (cooling), από μετεωρική εξαλλοίωση (weathering), από τεκτονική καταπόνηση (deformation) και από ανακρυστάλλωση (annealing).Ο ιστός δίνει πληροφορίες για τις συνθήκες γένεσης του κοιτάσματος, για τον μεταμορφισμό, για τον τεκτονισμό , για την εξαλλοίωση, για την ανακρυστάλλωση, για τον εμπλουτισμό του μεταλλεύματος και για τον τρόπο που μπορεί να γίνει η απόληψη του μετάλλου από το μετάλλευμα. Μικροσκοπικές μελέτες των ιστολογικών σχέσεων μεταλλευμάτων χρησιμοποιούνται για να διευκρινιστούν οι ορυκτολογικές παραγενέσεις , δηλαδή η σειρά αποθέσεως των μεταλλικών ορυκτών. / The field of this diploma thesis is the stady, the categorisation and the classification of the ore mineral textures. Collecting informations, we created an Atlas including the approaching description of the categories of ore mineral textures and the texture relations depiction of macroscopic, microscopic pictures and diagrams. Texture is a reciprocal regulation and relation of crystals,one or different minerals in space (in three dimensions). It can be observed with naked eye but mainly with the microscope. Textures can be classified to Primary Textures and Secondary Textures.Primary textures can form by subsidence of the crystals from melts and hydrothermal solutions. Secondary textures can be produced from cooling, weathering, deformation kai annealing. Textures inform you about deposits genesis conditions, metamorphism, pressure deformation, weathering, annealing, about ore enrichment and the way of the ore mineral seperation from the ore. Ore texture relations microscopic reseaches can be used to clarify mineral compositions, thus the ore mineral deposition order.

No description available.

I detta arbete har polerprov framställts för att därefter undersökas med malm- och svepelektronmikroskopi (SEM) med energidispersiv röntgenspektroskopisk analys (EDS). Med dessa metoder har mineralsammansättning, strukturer och texturer identifierats och undersökts. De undersökta proverna kommer från borrkärnor genom malmzonen i Lovisagruvan i Bergslagen, södra Mellansverige. Malmen är en tabulär, silverförande Zn-Pb-sulfidmineralisering.  De kombinerade undersökningarna av polerproven visar att de huvudsakligen består av zinkblände, blyglans, kvarts, mikroklin, granat, amfibol och pyrit, vilka karakteriseras av texturer som visar på omkristallisation, heterogen deformation och lokal remobilisering. De uppvisar småskaliga texturer som sannolikt är direkt relaterade till uppkomsten av s.k. kulmalmstextur. De ingående mineralens inbördes relationer tyder på att blyglans och zinkblände bildades samtidigt och därefter, under regionalmetamorfa förhållanden, tillväxte pyrit och granat som porfyroblaster. Majoriteten av texturerna och strukturerna är sekundära och visar på en kraftig senare överprägling av malmen genom metamorfos och flerfasig deformation under olika tryck- och temperaturförhållanden. / In this project polished sections have been prepared for study by means of ore and scanning electron microscopy (SEM) with energy dispersive x-ray spectroscopy (EDS). The application of these methods allows mineralogy, structures and textures to be characterized. This was done within the EU H2020-funded project X-Mine. The studied samples are from drill cores transecting the ore zone of the Lovisa mine (Lovisagruvan), which is located in Örebro County in the Bergslagen ore province, south central Sweden. Here, a tabular, stratiform silver-bearing Zn-Pb sulphide ore is mined.  Studies of the polished ore sections show that the samples mainly contain sphalerite, galena, quartz, microcline, garnet, amphibole and pyrite, characterized by textures of recrystallisation, heterogeneous deformation and localized remobilization.  The studied samples from the main ore and exhibit textures directly related to the formation off the so-called ball ore. The textural interrelationships of the major minerals indicate that galena and sphalerite formed penecontemporaneously, and then under regional metamorphic conditions, pyrite and garnet formed as porphyroblasts. The majority of the present textures and structures are secondary, representing different stages of metamorphism and deformation under variable P-T-conditions, post-dating original ore formation. / Real-Time Mineral X-Ray Analysis for Efficient and Sustainable Mining, H2020 X-Mine, Projekt-id: 730270

Les roches vulcanogéniques de la Mine de Seival appartiennent à la Formation Hilário du Bassin de Camaquã, d’âge Néoprotérozoique. Ces roches contiennent six mines inactives avec diverses prospections de cuivre–argent. Les minéralisations semblent associées à un contrôle structurel intense du régime ruptile. La compréhension de la transformation chimique de l’hydrothermalisme associé aux paléo-contraintes est assez faible dans la région. Nous proposons de caractériser la chimie des minéraux des phases magmatiques, tardi–magmatiques et hydrothermales ainsi que de comprendre les contraintes structurales et la géochimie des veines tardives de barytine et calcite. Pour ce faire, nous avons effectué des analyses minéralogiques, et chimiques des phases magmatiques et d’altération. La chimie minérale associée à la modélisation thermodynamique a permis de caractériser l’altération comme tardi– magmatique. L’albitisation (650 à 350 °C) s’est produite en association avec une chloritisation (312 à 120 °C) et avec de la pyrite et de la chalcopyrite. Les températures les plus basses (150 à 50 °C) ont été reliées à la formation de smectite et d’inter-stratifié de chlorite/smectite et avec de la chalcocite–covellite, chalcocite–bornite ou barytine. Nous effectuons les analyses structurales des mesures de cinématique et de la direction des failles/fractures. L’analyse structurale a montré trois contraintes principales survenant dans la Mine Seival et dans le District Minier de Lavras do Sul : compression NW–SW ; compression NE–SW ; distension ENE–SWS. La contrainte NW–SE est la principale direction de contrainte associée à la minéralisation et aux filons minéralisés dans ces deux régions. / The volcanogenic rocks of the Seival Mine belong to Hilário Formation from Camaquã Basin, with ages Neoproterozoic. These rocks contain six inactive mines with various prospects of copper-silver. Mineralization are associated with intense structural control in brittle regime. Chemical transformation of hydrothermal alteration associated with paleostress is not very well understood in the region. We propose a characterization of mineral chemistry of the magmatic phases, tardi–magmatic and hydrothermal as well as understand the paleostress and geochemistry of late veins. For this, we realized analyses of mineral chemistry of magmatic and alteration phase. Mineral chemistry coupled with thermodynamic modeling allowed to characterize the alteration as tardi–magmatic. The albitization (650 to 350 °C) occurred in association with chloritization (312 to 120 °C), and with pyrite and chalcopyrite. The lowest temperatures (150 to 50 °C) were related to formation of smectite and interlayered chlorite/smectite, and with chalcocite–covellite, chalcocite–bornite or barite. We perform structural analyzes through kinematic measures and failure/fracture directions. The analysis on faults, fractures and mineralization showed three main stresses occurring in the Seival Mine and Lavras do Sul Mining District: NW–SE compression; NE–SW compression; ENE–SWS distension. The NW–SE paleostress is the main effort related to the dikes and mineralization in both areas.

<p>The aim of this study is to examine the knowledge and experience of the bad breath among high school students in Kristianstad. A further objective was to measure the amount of VSC (Volatile Sulfur Compounds) among those who perceive themselves to have a bad breath. A questionnaire with 21 closed questions was distributed to 120 high school students from Kristianstad municipality who were between the ages of 17-20. The results of this study revealed that most of the students had good knowledge of halitosis. The majority of all participants thought it was important to smell fresh in the mouth and also experienced most of their breath as very good or good. Only a few felt that they had bad breath. However, these persons did think their breath affect their everyday life. Furthermore, they have never felt embarrassed or caught in embarrassing situations due to their breath. The results from the clinical examination was carried out on 8 of the 120 students and was designed to measure the amount of sulphurous gases in the oral cavity which revealed that the average values that emerged in the examination below is the limited values for having a poor breath.</p> / <p>Syftet med denna studie var att undersöka kunskapen och upplevelsen av dålig andedräkt hos gymnasieelever i Kristianstad, ytterligare ett syfte var att mäta mängden VSC (reaktiva svavelföreningar)  hos dem som upplever sig ha dålig andedräkt. En enkät med 21 slutna frågor delades ut till 120 gymnasieelever som var mellan 17-20 år och studerade i Kristanstads kommun. Av resultatet i denna studie framkom att de flesta av gymnasieeleverna hade goda kunskaper om halitosis. Nästan alla 120 som besvarade enkäten tyckte att det var viktigt att lukta fräsch i munnen och dessutom upplevde de flesta sin andedräkt som mycket bra eller bra. Endast ett fåtal (14% ) kände att de ibland hade dålig andedräkt. Hos dessa  påverkades inte andedräkten deras vardagliga liv och de hade aldrig blivit generade eller hamnat i pinsamma situationer på grund av sin andedräkt. Resultatet från den kliniska undersökningen som gjordes på 8 av de 120 elever som besvarade enkäten där mängden av de svavelhaltiga gaserna i munhålan mättes visade att i genomsnitt ligger värden som framkom i undersökningen under gränsvärden för att man skall ha dålig andedräkt.</p>

The aim of this study is to examine the knowledge and experience of the bad breath among high school students in Kristianstad. A further objective was to measure the amount of VSC (Volatile Sulfur Compounds) among those who perceive themselves to have a bad breath. A questionnaire with 21 closed questions was distributed to 120 high school students from Kristianstad municipality who were between the ages of 17-20. The results of this study revealed that most of the students had good knowledge of halitosis. The majority of all participants thought it was important to smell fresh in the mouth and also experienced most of their breath as very good or good. Only a few felt that they had bad breath. However, these persons did think their breath affect their everyday life. Furthermore, they have never felt embarrassed or caught in embarrassing situations due to their breath. The results from the clinical examination was carried out on 8 of the 120 students and was designed to measure the amount of sulphurous gases in the oral cavity which revealed that the average values that emerged in the examination below is the limited values for having a poor breath. / Syftet med denna studie var att undersöka kunskapen och upplevelsen av dålig andedräkt hos gymnasieelever i Kristianstad, ytterligare ett syfte var att mäta mängden VSC (reaktiva svavelföreningar)  hos dem som upplever sig ha dålig andedräkt. En enkät med 21 slutna frågor delades ut till 120 gymnasieelever som var mellan 17-20 år och studerade i Kristanstads kommun. Av resultatet i denna studie framkom att de flesta av gymnasieeleverna hade goda kunskaper om halitosis. Nästan alla 120 som besvarade enkäten tyckte att det var viktigt att lukta fräsch i munnen och dessutom upplevde de flesta sin andedräkt som mycket bra eller bra. Endast ett fåtal (14% ) kände att de ibland hade dålig andedräkt. Hos dessa  påverkades inte andedräkten deras vardagliga liv och de hade aldrig blivit generade eller hamnat i pinsamma situationer på grund av sin andedräkt. Resultatet från den kliniska undersökningen som gjordes på 8 av de 120 elever som besvarade enkäten där mängden av de svavelhaltiga gaserna i munhålan mättes visade att i genomsnitt ligger värden som framkom i undersökningen under gränsvärden för att man skall ha dålig andedräkt.

De sulfidgruvor belägna i Långbantrakten som studien behandlar ligger i den västra delen av Bergslagen utanför Filipstad i Värmlands län. Opaka mineral (malm) från två mindre mineraliseringar, Näset och Getberget, har studerats med malmmikroskop och mikrosond för att beskriva mineralogin i området. Båda områdena domineras av olika (Cu-Fe-Pb-Zn)-sulfider, i Näset av kopparkis (CuFeS2), blyglans (PbS) och zinkblände ((Zn,Fe)S) och i Getberget av blyglans, zinkblände, kubanit (CuFe2S3) och magnetkis (Fe1-xS). I Näset finns en del mindre frekventa mineral, två olika faser av Co-pentlandit (en nickelrik och en utan nickel), gedigen Sb och Bi, (Ni-Co)-sulfid, breithauptit (NiSb) och magnetkis. Kubanit är även ett viktigt mineral som speglar mineraliseringens bildning. I Getberget finns liknande mindre frekventa mineral, kopparkis, nickelrik Co-pentlandit, gedigen Bi och Sb, silverglans (Ag2S), breithauptit och magnetit (Fe3O4). En sen utfällning av kubanit har skett i båda områdena och visar att mineraliseringarna har genomgått en liknande bildning och det stämmer även in på mineralogin, som även den är likartad. / The small sulphide mines, Näset and Getberget that have been investigated are located just outside the main mineralization of Långban, near the city of Filipstad in Värmland County. Opaque minerals have been studied in reflected light microscopy and with an electron microprobe analysis to describe the mineralogy. Both areas are dominated by various (Cu-Fe-Pb-Zn)-sulphides, Näset with chalcopyrite (CuFeS2), galena (PbS) and sphalerite ((Zn,Fe)S) and Getberget with, galena, sphalerite, cubanite (CuFe2S3) and pyrrhotite (Fe1-xS). The sulphides are also accompanied by various accessory minerals, in Näset by two different phases of Co-pentlandite (on rich in nickel and one without), native Sb and Bi, a (Ni-Co)-sulphide, breithauptite (NiSb) and pyrrhotite. Cubanite is also a very important mineral that reflects the formation of the mineralization. In Getberget there are similar accessory minerals, chalcopyrite, nickel rich Co-pentlandite, native Bi and Sb, acanthite (Ag2S), breithauptite and magnetite (Fe3O4). A late precipitation of cubanite has occurred in both areas, suggesting that the mineralizations has been formed in similar conditions. This also holds true when comparing the mineralogy, which also is similar.

No description available.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / A discriminação de fases que são praticamente indistinguíveis ao microscópio ótico de luz refletida ou ao microscópio eletrônico de varredura (MEV) é um dos problemas clássicos da microscopia de minérios. Com o objetivo de resolver este problema vem sendo recentemente empregada a técnica de microscopia colocalizada, que consiste na junção de duas modalidades de microscopia, microscopia ótica e microscopia eletrônica de varredura. O objetivo da técnica é fornecer uma imagem de microscopia multimodal, tornando possível a identificação, em amostras de minerais, de fases que não seriam distinguíveis com o uso de uma única modalidade, superando assim as limitações individuais dos dois sistemas. O método de registro até então disponível na literatura para a fusão das imagens de microscopia ótica e de microscopia eletrônica de varredura é um procedimento trabalhoso e extremamente dependente da interação do operador, uma vez que envolve a calibração do sistema com uma malha padrão a cada rotina de aquisição de imagens. Por esse motivo a técnica existente não é prática. Este trabalho propõe uma metodologia para automatizar o processo de registro de imagens de microscopia ótica e de microscopia eletrônica de varredura de maneira a aperfeiçoar e simplificar o uso da técnica de microscopia colocalizada. O método proposto pode ser subdividido em dois procedimentos: obtenção da transformação e registro das imagens com uso desta transformação. A obtenção da transformação envolve, primeiramente, o pré-processamento dos pares de forma a executar um registro grosseiro entre as imagens de cada par. Em seguida, são obtidos pontos homólogos, nas imagens óticas e de MEV. Para tal, foram utilizados dois métodos, o primeiro desenvolvido com base no algoritmo SIFT e o segundo definido a partir da varredura pelo máximo valor do coeficiente de correlação. Na etapa seguinte é calculada a transformação. Foram empregadas duas abordagens distintas: a média ponderada local (LWM) e os mínimos quadrados ponderados com polinômios ortogonais (MQPPO). O LWM recebe como entradas os chamados pseudo-homólogos, pontos que são forçadamente distribuídos de forma regular na imagem de referência, e que revelam, na imagem a ser registrada, os deslocamentos locais relativos entre as imagens. Tais pseudo-homólogos podem ser obtidos tanto pelo SIFT como pelo método do coeficiente de correlação. Por outro lado, o MQPPO recebe um conjunto de pontos com a distribuição natural. A análise dos registro de imagens obtidos empregou como métrica o valor da correlação entre as imagens obtidas. Observou-se que com o uso das variantes propostas SIFT-LWM e SIFT-Correlação foram obtidos resultados ligeiramente superiores aos do método com a malha padrão e LWM. Assim, a proposta, além de reduzir drasticamente a intervenção do operador, ainda possibilitou resultados mais precisos. Por outro lado, o método baseado na transformação fornecida pelos mínimos quadrados ponderados com polinômios ortogonais mostrou resultados inferiores aos produzidos pelo método que faz uso da malha padrão. / The discrimination of phases that are practically undistinguishable to the optical microscope of reflected light or to the scanning electron microscope (SEM) is one of the classical problems in ore microscopy. With the aim of solving this problem it has been recently used the technique of co-located microscopy that consists in the junction of two microscopy modalities, optical microscopy and scanning electron microscope. The aim of the technique is to provide an image of the multimodal microscopy, becoming possible the identification, in mineral samples, of phases that wouldnt be distinguished by the use of one modality only, overcoming the individual limitations of the two systems. The method of register available so far in literature to the fusion of optical microscopy and scanning electron microscope images is a hard-working procedure and extremely dependent on the operator interaction, once it involves the system calibration with a standard mesh in each routine of images acquisition. Due to this reason the current technique is not practical. This piece of work proposes a methodology in order to automate the process of images register in optical microscopy and scanning electron microscopy in a way to improve and simplify the co-located microscopy technique. The proposed method may be divided in two procedures: acquisition of transformation and register of the images with the use of this transformation. The acquisition of transformation involves, first, the pre-processing of pairs in a way of performing a crude register among the images of each pair. Then, homologous points are achieved in the optical and in SEM images. In order to this, it has been used two methods, the first one was developed based in algorithm SIFT and the second was defined from the sweeping of the highest of coefficient correlation. In the following step it is calculated the transformation. Two different approaches were used: the local weighted mean (LWM) and the weighted least squares with orthogonal polynomials (MQPPO). The LWM receives as entrance what we call pseudo-counterparts, points that are distributed in a regular way in the reference image, and that reveal, in the image to be registered, the relative local dislocation among the images. Those pseudo-counterparts may be obtained by SIFT or by the method of correlation coefficient. On the other side, the MQPPO receives a group of points with natural distribution. The analysis of the images registration obtained employed as a metric the value of correlation among the obtained images. It was noticed that with the use of the proposed variants SIFT-LWM and SIF-Correlation were obtained slightly higher results than the ones from the method with standard mesh and LWM. Thus, the proposal, besides reducing drastically the operator intervention, still enabled more exact results. On the other side, the method based in the transformation provided by the minimum square pondered with orthogonal polynomial showed lower results than to the ones produced by the method that used standard mesh