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

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.

The thesis comprehensively investigates 2 pcs of ferrous and 14 pcs of bronze Celtic artefacts from a region of Zdejciny by Beroun. The study by means of ore microscopy, x-ray fluorescent microspectrometry, chemical microanalysis, Raman microspectrometry and x-ray powder diffractive analysis has showed that the bronze artefacts are made mainly of bronze. The phases present in the studied items correspond to fields and + of the Cu-Sn phase diagram. Content of Sn in bronze ranges between 4 and 33 wt.%. For the bronze selected items there was also Vickers microhardness measured. There were two artefacts where areas with a significant lead enrichment were found. Corrosive products were also deeply analysed and identified.

One of the major challenges in earth sciences and mineral exploration has been to determine with high accuracy and at a fast rate the elemental composition as well as the general chemistry of a rock sample. Many analytical techniques e.g., scanning electron microscopy (SEM) have been employed in the past with a certain degree of success, but their analyses usually require a lengthy sample preparation and time-consuming measurements which produce results at a much slower rate than techniques whichrequire less or do not require any sample preparation at all. SEM images the surface of a sample by scanning it with a high-energy beam of electrons in a raster scan pattern, where the primary electron beam produced under very low air pressure vacuum scans across the sample by striking it, and a variation of signals produce an image of the surface, or its elemental composition together with energy dispersive X-rays. Alternatively, laser induced breakdown spectrometry (LIBS) and multi energy X-ray transmission (ME-XRT) are non-contact measurement scanning techniques, capable of producing faster results than SEM-EDS which makes them suitable for real time measurements and analyses as they do not slow down the pace of a project being carried out. LIBS is a spectroscopic technique used to characterize and detect materials where a highly energetic laser pulse is focused onto the surfaces of solids, liquids or gases resulting in atomic and molecular species to emit light at specific wavelengths which is collected with a spectrometer and analysed using a computer. Comparably, ME-XRT is a sensor-based sorting technique involving the planar projection of X-ray attenuation of a particle stream, distributed on a fast conveyor belt, where they are scanned and evaluated while passing and an image is recorded by a line scan detector.      Eleven rock samples were analysed in this study. They include four rock type samples: granite, basalt, sandstone, and gneiss, all obtained from Luleå University of Technology (LTU) sample storage and seven ore type samples which include a porphyry Cu sulphide ore, a porphyry Cu oxide ore, a porphyry Cu-Au-Ag ore, an apatite iron ore (AIO), an iron-oxide copper gold ore (IOCG), an orogenic gold ore and a volcanogenic massive sulphide ore (VMS).       The SEM results give a semi-quantitative elemental composition of the rocks, which may be usedto discriminate mineralisation. Energy dispersive X-ray spectroscopy (EDS) maps may be used to identifygeological features and secondary electron (SE) images may be used to understand the topography of the rock samples. The SEM has a low penetration depth rate but produces moderate to high accuracy resultsdepending on the settings and calibrations. It requires a lengthy sample preparation, and its analytical time is often too long for routine industrial application. LIBS results also provide rock elemental compositions similar to the SEM, which may be quantitative if the same spectrometer is used for all elements and calibrated against a standard. It also produces element maps similar to the SEM-EDS maps. LIBS analyses yield high accuracy results but at a low penetration depth. There are no standard calibrations for the LIBS measurements, which limits quantification. LIBS measurements do not require any form of sample preparation. ME-XRT analyses result in rock chemical data portraying a light material fraction (aluminium-like) and a heavy material fraction (iron-like) which may be used to distinguish different rock samples based on the closeness of their effective atomic number Zeff to that of aluminium and iron respectively. It’s analysis also produces low-resolution images of the analysed rock samples. The image resolution is too low to allow interpretation of the data in the context of the structures and textures in the rock samples. It has a higher penetration depth than LIBS and SEM-EDS producing more volumetric data but with a lower accuracy in terms of the amount of information obtained. Only two elements are used for ME-XRT calibration measurements, if many elements of varying atomic numbers could be used, it would have the ability to provide a more reliable data. Samples must have a maximum and minimum thickness; thus, sample preparation is required to regulate the rock thickness.      SEM and LIBS provide element compositions of minerals and element distribution maps required by geologist in their daily activities during exploration and mining. This information can be considered the most useful obtained from all three techniques. However, LIBS analyses are faster, and its maps are of higher quality even at the same resolution as the SEM-EDS. This makes the LIBS preferable for real time measurements and analyses. Geological activities like drill core logging, mine mapping and sampling for grade control all require fast results for project continuity and LIBS is suitable for this purpose as it can keep up with the pace of these activities. SEM analytical technique provides semi-quantitative data which is more accurate than the LIBS data and thus, preferable for usage in research institutions and universities.ME-XRT can reveal information on the internal structures or different rock sample compositions. This makes it a suitable technique in distinguishing ore from waste material especially in iron ore mining and processing where the iron needs to be separated from the siliceous waste and sorting is also required prior to beneficiation to avoid equipment destruction by abrasive quartz. LIBS and ME-XRT analytical techniques complement each other in terms of analytical capabilities as LIBS has a low penetration depthrate but high accuracy results while the ME-XRT has a high penetration depth rate but low accuracy results. They are both fast scanning techniques that can be used for real time measurements and analyses and if their analytical prowess can be improved, the combination of these two fast analytical techniques may enable us to obtain high quality data and may as well be what is needed by geologists in the future.