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An optical microscope coupled to a flow cell was used to investigate ice nucleation on five atmospherically relevant mineral dusts at temperatures ranging from 233 to 247 K. Kaolinite and muscovite particles were found to be efficient ice nuclei in the deposition mode, requiring relative humidities with respect to ice (RHi) below 112% in order to initiate ice crystal formation. Quartz and calcite particles, by contrast, were poor ice nuclei, requiring relative humidities close to water saturation before ice crystals would form. Montmorillonite particles were efficient ice nuclei at temperatures below 241 K, but poor ice nuclei at higher temperatures. In several cases, there was a lack of quantitative agreement between these data and previously published work. This can be explained by several factors including mineral source, particle size, observation time and surface area available for nucleation. Heterogeneous nucleation rates (Jhet) were calculated from the onset data. Jhet values ranged from 60 to 1100 cm-²s-¹ for the five minerals studied. These values were then used to calculate contact angles (θ) for each mineral according to classical nucleation theory. The contact angles measured for kaolinite and muscovite ranged from 6 to 12º; for quartz and calcite the contact angles were much higher, ranging from 25 to 27º. The contact angles measured for montmorillonite were less than 15º at temperatures below 241 K, and above 20º at higher temperatures. The reported Jhet and θ values may allow for a more direct comparison between laboratory studies and can be used when modeling ice cloud formation in the atmosphere. The roles of H₂SO₄ and (NH4)₂SO₄ coatings on the ice nucleating properties of kaolinite were also investigated. Onset data was collected for H₂SO₄ coated and (NH4)₂SO₄ coated kaolinite particles at temperatures ranging from 233 to 247 K. In contrast to uncoated kaolinite particles, which were effective ice nuclei, H₂SO₄ coated particles were found to be poor ice nuclei, requiring relative humidities close to water saturation before nucleating ice at all temperatures studied. (NH4)₂SO₄ coated particles were poor ice nuclei at 245 K, but effective ice nuclei at 236 K.

There has been considerable research over the years regarding the relationship between natural resource abundance and economic growth, yet much less is known about the link between natural resource abundance and prevalence of poverty. This thesis examines the question of whether mineral resource rents have helped to reduce poverty rates in countries with an extensive mineral base in a cross country case study analysis involving Botswana, Nigeria, Zambia, Bolivia, Chile, and Venezuela. The link between mineral rents and poverty is studied in the context of four major mechanisms; (1) the redistribution of resources across sectors of the economy (‘Dutch Disease’), (2) the distribution of rents between the domestic country with the natural resources and foreign extraction firms, (3) the allocation of resources among citizens, and (4) the reallocation of rents over time (for precautionary saving). While none of the countries have achieved substantial economic diversification, Chile emerges as the best performer in this case study. Chile has utilized its extensive mineral base to achieve strong economic growth as well as significant poverty reduction. Facilitating an encouraging private investment climate or a mix of public and private ownership that does not sacrifice productivity and efficiency seems to work in appropriating a stable and fair share of mineral rents. Rents that are prudently invested in the domestic economy, in foreign assets for precautionary saving, and in targeted policies designed to redistribute resources more equally among citizens can significantly reduce poverty, and increase social and economic development.

The Abhainn Srathain copper mineralisation with at least 10 million tonnes of rock containing copper was worked during the Eighteenth Century and is situated 1-2km to the south of Meall Mór, South Knapdale. The mineralisation is hosted by epidiorites, quartzites and schists of the Upper Erins Quartzite Formation in which the levels of copper reach up to 2%, 1.3% and 0.8% respectively. The main suiphide phases, pyrite and chalcopyrite, occur in disseminations, in layers and as large crystals in quartz and/or calcite cross-cutting veins. The observed opaque mineral textures are due to recrystallisation, deformation and limited mobilisation indicating a premetamorphic origin for the mineralisatlon. Microscopic compositional variation of the minerals and isotopic geothermometry of analysed pyrite-chalcopyrite pairs suggest disequilibriun conditions during the regional metamorphism. Sulphides contain low minor element concentrations with a high Co:Ni ratio in pyrite (12.5:1). The mineralisation is associated with the local development of epidote, Mn-rich garnet, chlorite, muscovite and calcite and/or quartz cross-cutting veins which all resulted from premetamorphic alteration during ore formation. During this alteration CaO, Fe₂0₃, CO₂, MnO, Cu, S and some trace elements were added, Al₂0₃ was diluted and MgO, FeO, alkalis and some trace elements were removed. The isotopic composition of bacteriogenically reduced sulphur from sulphides throughout the Knapdale Pyrite Horizon ranges between o³⁴s=+4.5 and 12.8 per mil. The consistent isotopic values of the suiphides from the Abhainn Srathain copper mineralisation with an average of around +7 per mil regardless of location, depth, lithology and style of mineralisation suggest that the source of the hydrothermal sulphur is a mixture of inorganically reduced downward percolating Dalradlan seawater sulphate and sulphur leached from interbedded basic igneous rocks. Weak exhalative activity caused by the shallow intrusion of sill bodies into the wet unlithified sediments of the Lower and Upper Erins tiartzite accompanied the deposition of the Upper Erins Quartzite and is expressed by weak disseminated and stratiform pyrite with traces of chalcopyrite and sphalerite (Knapdale Pyrite Horizon). Increasing intensity of this exhalation was due to the creation of a geothermal system centred at the site of the present copper mineralisation. During this stage the hot ascending water reacted with the rocks causing local alteration and precipitation of pyrite and chalcopyrite as disseminations, layers and cross-cutting veins. At the same time cold water descended into the hot intrusives and altered the rocks by dissolving silica and precipitating calcite and oxides.

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