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The alteration at the low-sulphidation epithermal Banderas Au-Ag prospect, Guatemala, was characterized using a portable infrared mineral analyzer (PIMA) spectrometer and shown to comprise illite, buddingtonite and, on surface, kaolinite associated with gold mineralization. The Spextract python program, developed by the author, was used to measure variations in the short-wave infrared spectra (SWIR) which were then mapped as equal-area-of-influence or voronoi diagrams. Voronoi maps of the 2200 and 2350 nm absorption features, position and depth, respectively, for illite and 1560 and 2120 nm feature depths for buddingtonite indicate that illite crystallinity and ammonium alteration intensity increase towards gold mineralization. The latter observation suggests that gold transport and deposition may have been controlled by ammonia complexation. At conditions likely to have prevailed during mineralization, i.e., temperatures between 150° and 250°C, a pH between 5 and 8.5, an oxygen fugacity ( fO2 ) near the hematite-magnetite buffer, a chlorinity of 0.5 m, a total sulfur activity of 0.001 m, and a total nitrogen activity of 0.004 m, AuNH3 +2 is the dominant ammonia complex and gold solubility at optimal pH- fO2 conditions reaches ∼65 ppm at 250°C. In contrast, the maximum solubility of gold as AuHS -2 , the species normally assumed to control gold transport in epithermal systems, is approximately four orders lower at 250°C; at 150°C the solubility of AuNH3 +2 and AuHS -2 are essentially the same, i.e., ∼9 ppb. A model for Au-Ag mineralization is proposed in which hydrothermal fluids were focused along NW-SE extensional faults and at the contacts of rhyolite domes and tuffs, and gold transport and deposition were controlled mainly by ammonia-dominated complexation and boiling-induced temperature decrease, respectively.

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Abstract 150 years ago, the carefully-planned Presbyterian settlement of Dunedin was torn apart by the discovery that nearly every stream in Otago was laden with gold. The population exploded, adding the accents of Greece, Tipperary, Victoria, California, Guangdong and the King Country to the Scots burr which had been predominant. Almost immediately a myth of identity emerged, typified by goldfields balladeer Charles Thatcher’s ‘Old Identity and New Iniquity’ and boosted by the histrionics of a press enamoured of the romanticised machinations of the Otago goldfields ‘digger’. This popular mythology conflates the imagery of California, Victoria and early Gabriel’s Gully to perpetuate stories of desperate, gold-mad miners swarming across the province fighting, drinking and whoring away sparse winnings in a vast and lawless land, where bodies float down the Clutha, diggers battle corrupt police and vast fortunes are won and lost. This thesis seeks to construct a de-mythologised account of the rush for Central Otago gold, examining the engineering processes, social dynamics and communal relationships implicit in the development of claims, the construction of goldfields structures, the growth of towns and the emergence of financial networks. This explains and reveals the social, technological and economic developments of the gold rush that wrought a profound change on the Otago landscape and to New Zealand’s history. Focussing on the New Zealand Department of Conservation’s historic reserve at Bendigo as an exemplary site, this thesis focuses on the people of the goldfields who left traces of themselves in archives, letters, newspapers, court records and in the heritage landscape to explain their mining, commercial and family lives, and concludes by exploring the remnants of their existence in the relic-strewn ghost-town. By elucidating the depth and breadth of relationships, processes and lives of the residents, miners and merchants, I refute the pervasive myth of innocent simplicity around the era to replace it with a surprisingly complex reality. This complexity is revealed in the new conclusions I draw around the myriad processes behind identity formation, rush events, water race construction, quartz mine development and labour relations, merchant finances and heritage remnants.

Currency carry trade is an investment strategy that recently started gaining a lot of interest not only among investors and financial institutions but also academically. One of the underlying theoretical assumptions regarding the mechanisms of the foreign exchange market, the Uncovered Interest Parity has frequently been disproved in practice which has led to the conclusion that carry trade is profitable in practice. The function of a carry trade strategy is that a short position is taken in a low interest rate currency to finance a long position in another currency offering higher yields. This thesis is adding to the existing literature that is explaining the characteristics of currency carry trade but is adopting a different approach than most other recent researches that has focused on identifying especially risk factors. Gold as a financial asset has also received much attention largely due to its, contrarily to other asset classes, low dependence on macroeconomic factors. This makes gold desirable to diversify portfolios and decreasing overall risks. By investigating how the returns of currency carry trades and gold relates to each other an increased understanding in how carry trades can be beneficially included in managing portfolios are developed. Looking at a currency carry trade index, Deutsche Bank’s G10 Currency Future Harvest index, and the development of the gold price at the London bullion market for the 20 year period of 1993-2013 this research is exploring correlation, mean and volatility spillover effects. Spearman’s correlation, Vector Autoregression and a diagonal BEKK GARCH model are employed to test these effects. It also investigates if gold possesses hedge, diversifier and safe haven characteristics when combined with carry trades as it has been found to do with stock markets. This is determined by a regression analysis and supplemented by a portfolio simulation. This thesis found that there is a low positive correlation between the returns of gold and currency carry trades and that there is spillover effects as well between the two in both returns and volatility. This in addition to the regression analysis and portfolio analysis determined that there are diversification benefits by adding gold to a portfolio consisting of currency carry trade in the form of higher risk adjusted returns. However special caution has to be taken to the spillover effects as these complicate the relationship between the returns of the two variables and especially the volatility spillover effects slightly decreases the potential diversification benefit. The regression analysis concluded that gold work as a diversifier for carry trade but could not determine if it also exhibited hedge or safe haven characteristics. These findings pushes the existing understanding of carry trades forward and adds to focus of matching carry trades within a portfolio which could have implications to more efficiently match risks and returns by combining several asset classes in portfolio management.