Chuquicamata mine mineralogy has been studied performing both X-Ray Diffraction (XRD) and X-RayFluorescence (XRF) to determine whether there is any influence in the thickener operations. Thetargeted minerals were the clay group because of their detrimental effect on mining operations asmodify the rheology of the suspensions. The operation stages most affected by the presence of the clayminerals are gravity separation, milling, conveyor belts, flotation and specially thickener operations. Inorder to cope with Chuquicamata production, the plant is constantly fed from a neighboring ore calledRadomiro Tomic (RT) ore, a secondary sulfide enrichment. At Chuquicamata, the thickener operatorfeedback has been pointed out that every time the concentrator plant is fed in high ratio with this so-called RT ore the mineral processing is hindered. For this reason, RT ore samples from a criticaloperation day were sent to Sweden for mineralogical analysis. In addition, flotation tailings from thethree Chuquicamata concentrator plants were also sent aimed to perform thickener pilot tests. In thismanner, it was seen if it could be possible to achieve new operational strategies in Chuquicamatathickener operations given the current Chuquicamata mineralogy and physical conditions in the flotationtailings.From the XRD analysis, the following clay minerals were identified in order of abundance: Illite>>Kaolinite>Smectite Thus, illite reached up to 23.3vol% being the highest clay amount, followed by lower case kaolinite up to2.5% and up to 1% of smectite values correspond for the RT sample. However, the clay content in theflotation tailings samples were less than expected. Also, clay Crystallinity was also assessed for its abilityto interfere negatively with the pulp rheology, and the results showed that there is a strong link amongpoor crystallized smectite clay with the semi-autogenous mill compare to those samples where themilling was performed in the traditional steel media. Along with the three clay minerals found, quartz,potassic feldspar, and plagioclase were also identified, accounting for up to 76% of the representativesample. The silicate minerals are thought to be problematic in Chuquicamata thickener operations givenits high amount, especially in <2 µm size.For the thickener tests, three types of polyacrylamide were used plus the current Chuquicamataflocculant. Prior to the sedimentation batch test, the rheology of the flocculants was measured in arange of 0.02%w/w to 1%. It was found that flocculant concentrations between 0.02 to 0.05%w/w themost suitable in terms of avoiding suspension rheology increase. After establishing suitable flocculantconcentrations solutions, these were used in the thickener pilot tests at conditions similar to thoseperformed in Chuquicamata thickener operations. Two criteria were used to analyze the bestsedimentation conditions: Initial settling rate (ISR); and Turbidimeter. At pH in a range of 11-12 and 15%solid, bridging flocculation probed to be the most suitable conditions for Chuquicamata thickeneroperations. Moreover, a polyacrylamide blend was tested aiming to achieve high sedimentationperformances. The flocculant blend reached both the highest initial sedimentations rate up to 48m/hand turbidity values below 20NTU at addition rate 5g/t and 7g/t. On the other hand, Chuquicamatacurrent flocculant only reached the highest values of 36m/h and turbidity of 40NTU at an addition rateof 5g/t. In this way, the current work established that conditions at Chuquicamata thickener operation 4can be improved by understanding the absorption process among particle-polymer and mineralogy ofthe mine.Hence, the implication of this work to Chuquicamata mine is a better knowledge of its mineralogyespecially concerned with it is believed that clay minerals are not the only mineralogical factors thatcould be hindering thickener operations in Chuquicamata. Other factors that also could be problematicare: high content of silicates; clay crystallinity, particle size and mixed clay. In addition, the improvementin the thickener sedimentation operations will bring better use of the water by increasing therecirculation towards the concentrator area in a friendly way with the environment and communitiesthat also demand water in the arid region of the Atacama Desert.

Premenstrual syndrome (PMS) is characterized by the presence of physical and psychological symptoms restricted to the late luteal phase of the menstrual cycle and associated with substantial impairment in life activities. In the U.S. about 8 to 15% of women of reproductive age suffer from PMS. Many micronutrients are potentially involved in the development of this disorder due to their role in the synthesis of neurotransmitters and hormones or in their regulation, but few previous studies have evaluated the effects of micronutrients on PMS. The first study examined the association between B vitamin intakes, and PMS development among women participating in the Nurses' Health Study 2 (NHS2). We found that high thiamin and high riboflavin intake from food sources were associated with lower risk of PMS. There were not significant associations between niacin, vitamin B6, folate, and vitamin B12 dietary intake and incident PMS. Intakes of B vitamins from supplements were not associated with lower risk of PMS. The second study evaluated the association between selected mineral intakes and PMS development in the NHS2. In this study, high iron intakes were associated with lower risk of PMS. Although there was no association between zinc and PMS risk, high intake of zinc relative to copper was associated with lower risk of PMS. There were no associations between of magnesium, copper, and manganese intakes and PMS. We observed a significantly higher risk of PMS in women with high intakes of potassium from food sources. The third study focused on the association between dietary intakes of B vitamins, zinc, magnesium, iron, potassium, and sodium and some biomarkers and PMS prevalence among younger women. In this study, we found an association between zinc intake and lower prevalence of PMS. Each 1 mg/d increase in vitamin B6 from foods was associated with a lower PMS symptom score. Blood magnesium levels were higher in women with PMS compared to women without PMS. We observed that intakes of some micronutrients were associated with lower risk of PMS, but further studies should be conducted. This dissertation contributes to the research on modifiable risk factors for PMS.

Ni-laterites have the potential to become unconventional ore deposits for platinum group elements (PGE). This study was conducted to determine enrichment trends of PGE as a result of the Ni-laterization process. 6 samples were selected by mine workers from the protolith, saprolite, and limonite horizons of the Ni-laterite profile from the Acoje ophiolite block, Luzon, Philippines, and sent to Luleå University of Technology (LTU). 2 samples representing the protolith are described as dunite having undergone serpentinization, 1 sample is a massive chromitite from the saprolite layer of the laterite profile, 1 sample is a massive chromitite from the limonite layer of the laterite profile, and 2 samples are limonitic soils. Total PGE contents of the investigated Acoje samples range from 161-1180 ppb with the highest contents of PGE occurring in the limonite hosted chromitite, and the lowest contents in the saprolite hosted chromitite. C1 chondrite-normalized patterns reveal distinct trends of the PGE in the different sample types: dunite samples have a positive trend from Ir-Pd, the chromitite samples have a negative trend from Ru-Pd with a negative Ir anomaly and the limonite samples have a strong positive trend from Ir-Pd. Rare earth elements (REE) chondrite-normalized patterns of the samples show a negative Ce anomaly in the limonite while the dunite and saprolite-hosted chromitite have negative Eu anomalies. Cr# (Cr/[Al+Cr]) and Mg# (Mg/[Fe2++Mg]) were analyzed using automated mineralogy and produced Cr# values ranging from 0.67 – 0.77 and Mg# values from 0.46 – 0.59.  17 platinum group minerals (PGM) were identified from the Acoje samples: 9 from the dunite, 1 from the saprolite-hosted chromitite, 6 from the limonite-hosted chromitite and 1 from the limonite. Laurite ((Ru,Os)S2) was identified in samples A-02 and A-07 and is the only primary mineral identified. Secondary PGM, thought to have formed due to alteration processes during serpentinization, were identified as alloys composed of: Cu-Pd, Cu-Pt, Pt-Ni-Cu, Pt-Fe, Ir-Ni-(Pt,Fe), and Cu-Pt-Au-(Pd-Ag). PGM are small, measuring consistently <10 µm in diameter. Laurite occurs as inclusions in unfractured chromite. PGM alloys in the dunite samples occur along the boundary of sulfide minerals or within serpentine. PGM identified in the limonite-hosted chromitite occur along interstitial fractures within chromitite or in a Fe-Al oxide matrix within pore spaces.

Raman spectroscopy has been used to characterise both organic and geological samples in order to build a database for the future characterization of biomarker molecules that are of astrobiological relevance. Characteristic geological features and hydrated minerals recently found on the surface of Mars by the NASA planetary rovers Spirit and Opportunity suggest that a possible biosphere could have once existed there. Analytical instrumentation protocols for the unequivocal detection of biomarkers in suitable geological matrices are critical for future unmanned explorations, including the forthcoming ESA ExoMars mission scheduled for 2018. Several geological features found on the surface of Mars by planetary rovers suggest that a possible extinct biosphere could exist based on similar sources of energy as occurred on Earth. For this reason, analytical instrumental protocols for the detection of isolated biomarkers preserved in suitable geological matrices unequivocally and non-destructively have to be evaluated for future unmanned missions. Raman spectroscopy is currently part of the Pasteur instrumentation suite of the ExoMars mission for the remote detection of extant or extinct life signatures in the Martian surface and subsurface. Terrestrial analogues of Martian sites have been identified and the biogeological modifications resulting from extremophilic survival activity have been studied. Here we present the Raman spectral characterization of several examples of organic compounds which have been recorded using 785 nm, 633 nm and 514 nm laser excitation -polycyclic aromatic hydrocarbons (PAHs), organic acids, chlorophyll and carotenoids. Experimental mixtures of ß-carotene in usnic acid, PAHs in usnic acid and PAHs in mineral matrices have also been investigated. Organic compounds and PAHs located under crystalline minerals samples were identified using a 5x objective lens and 785 nm III excitation. The pure compounds and compound mixtures were also analysed using X-ray powder diffraction and scanning electron microscopy (SEM). The results of this study indicate that near infrared laser at 785 nm provided the clearest and the most informative spectra due to the reduction of fluorescence emission. Higher energy lasers operating in the visible region have resulted in the emission of significant background fluorescence. Few samples fluoresce even with the use of 785 nm excitation and FT-Raman spectroscopy remains the instrument of choice for the analysis of these samples.

Cancrinite specimens from Ontario were studied. Chemical and thermogravimetric analyses were made. Non-Bragg reflections were observed in x-ray photographs. These reflections have the same symmetry as the main lattice reflections, but the intensities, abundance and the relative positions of them with respect to the main lattice reflections are different from one specimen to another. In the heated specimens, the superstructure reflections decrease in intensities, shift in position and are streaked in a direction parallel to the a*-axis on the a* c* reciprocal lattice plane. Phase changes in the heated cancrinites show that the sodalite group of minerals occur as transitional phases in the cancrinite break down reactions. It is shown that the non-Bragg reflections are very similar to the main lattice reflections. There is a probable relation between the non-Bragg reflections in cancrinite and the sodalite group of minerals. / Thesis / Master of Science (MSc)

<p> A textural and mineralogical study of the magnetite, hemoilmenite and minor sulfide phases of the Whitestone anorthosite, Dunchurch, Ontario, was carried out. The composition of magnetite and hemo-ilmenite was determined by chemical analysis, X-ray diffraction and electron probe microanalysis. A modification of the solvus shape in the hematite-ilmenite system consistent with the composition of hemo-ilmenite lamellae, as well as a mechanism for formation of metamorphic magnetite porphyroblasts from ferrianilmenite is proposed. Buddington and Lindsley's experimental data cannot be used directly to obtain f02 and T of formation of the anorthosite because compositions fall in the highly oxidizing and as yet undetermined portion of their diagram. </p> / Thesis / Master of Science (MSc)

<p> A sequence of metasedimentary rocks comprising the George River Group, Cape Breton Island, Nova Scotia, was studied. A petrographic examination of the five different rock types present -- marbles, amphibolites, paragneisses, skarn xenoliths, and granitic bodies was carried out. A petrochemical analysis, using X.R.F. methods was also completed.</p> <p> The GRG has undergone three distinct periods of metamorphism. The first was a period of kyanite grade regional metamorphism, believed related to the Grenville orogeny. High grade metamorphic minerals developed in the various lithologies present in the GRG. These minerals were kyanite, diopside, forsterite, hornblende, and muscovite.</p> <p> A chlorite grade regional metamorphism followed, creating such low grade minerals as chlorite, sericite, and serpentine. These minerals formed by the hydrolysis of higher grade metamorphic minerals.</p> <p> Following this low grade metamorphism, the GRG was subjected to a period of wollastonite grade contact metamorphism. This metamorphic period resulted from the injection of smaller granitic bodies believed related to the Acadian orogeny. The formation of contact metamorphic minerals such as, wollastonite, vesuvianite, phlogopite and sphene characterize the assemblages formed by this metamorphic event.</p> <p> The petrochemical analysis shows that these meta-sedimentary GRG rocks had protoliths of several types, including siliceous dolomitic limestones, siliceous limestones, greywackes, and basic volcanic sills. The amphibolites present crossing the GRG formed by the metamorphism of the basic volcanic sills.</p> / Thesis / Bachelor of Science (BSc)

<p> The Lake Shore Mine has accounted for over a quarter of the gold produced in the Kirkland Lake camp. Petrography suggests that gold is a later phase in the paragenesis of ore minerals. Sulphides precipitated first followed by tellurides and gold. Wallrock alteration adjacent to the quartz veins was studied by thin section and geochemical analysis. Petrography enabled an alteration facies scheme based on predominant alteration minerals to be established. The alteration assemblages suggest the fluid had a high K and CO2 content, low Na, and reduced S content. Geochemical analysis of these samples confirm petrographic observations and suggests major additions of K2O, SiO2, Rb, Sb and Au to the wallrock, and losses of Na2O, Ba and Zr from the wallrock.</p> / Thesis / Bachelor of Science (BSc)

<p> Magnetization associated with the emplacement or a rock body may be thermo-remanent magnetization (TRM) in an igneous body or detrital-remanent magnetization (ORM) in a sedimentary deposit. At the time or Formation the acquired remanence will tend to lie in the ambient field direction. This primary remanence may not remain unchanged through geologic time. Viscous demagnetization may progressively destroy the remanence in the primary direction or it may be reset as VRM in a later different ambient field direction. The amount or acquired VRM will depend on the temperature the rock is heated to and the length or time the heating lasts as well as the magnetic properties or the remanence carriers.</p> <p> The remanence may also be changed by chemical reactions taking place in the magnetic minerals. The remanence acquired during these chemical changes (CRM) is round, by this work, to be a determining factor in the stability or and initial NRM during thermal remagnetization. </p> <p> Synthetic samples were stored for up to 32 days at 400 C it is possible to access geologic time. To simulate viscous changes over geologic time elevated temperatures applied for laboratory times are related to longer times at lower temperatures using the thermal activation curves. Changes in remanence during the storage were observed at various times throughout the experiment. The remanence in samples with an initial NRM was diminished, remanece in samples with a weak initial NRM increased in intensity but the remanence direction lay in the Field direction after as little as l/2 a day storage time. </p> <p> Thermal demagnetization allows separation of the magnetization on the basis of blocking temperature spectra. During the storage the initial magnetite was oxidized to cation deficent magnetite with significantly higher blocking temperatures than those found in the magnetite. Hysteresis measurements, and thermomagnetic mesurements indicate that this change results primarily From the shirt in Tc due to cation deficency. Apparently the change in T did not significantly affect the mechanisms responsible for blocking remanence but merely shifted the blocking temperatures by a similar amount. In samples with a weak initial NRM the chemical change completely reset the magnetization and in samples stored for times as short as only 8 days the initial remanence direction could not be recovered. </p> / Thesis / Bachelor of Science (BSc)

Although alpacas are not used for milk production a detailed knowledge on the composition of the colostrum and milk is needed for development of colostrum and milk replacers. The aim of the present study was to measure the concentration of fat, protein, lactose, and minerals in alpaca colostrum and milk. Colostrum samples were taken daily over four days after parturition from 20 multiparous alpaca mares. Milk samples were obtained monthly, during the first four months of lactation from 17 alpacas. Composition of colostrum and milk differed in numerous indicators. The concentrations of fat and lactose increased from day 1 (0.5%, 4.0%) to day 4 (5.3%, 5.0%), protein decreased from 20.4% on day 1 to 8.3% on day 4. In milk these three indicators did not change during the lactation. Minerals have been little studied in alpaca colostrum and milk in the past, many of which had the highest concentrations in colostrum immediately after birth. The results of the present study do not support that goat’s milk is the preferred substitute for feeding crias. This study contributes to the knowledge of the composition of alpaca colostrum and milk which can be of particular use in developing replacers.