A Metallurgical Study of Gold Ores

Gold is widely distributed in the earth's crust in small quantities. Gold is found in nature in two forms; the element itself and the compound gold telluride. In all cases, silver in some proportion is an alloying constituent.

The Inhibitory Effects of Carbonaceous Materials on the Cyaniding of Gold Ores.

Carbon and carbonaceous material have been known to have a deleterious effect upon the cyanidation of gold and silver ores since the very beginning of the process. Organic matter is a common source of impu­rities in cyanide solution, its reducing effect being notorious.

Stakeholder engagement and asset management : a case study of the Gold Coast airport, Queensland

One of the fastest growing industries – aviation – faces serious and compounding challenges in maintaining healthy relationships with community stakeholders. One area in aviation creating community conflict is noise pollution. However, current understandings of the factors that affect noise annoyance of the community are poorly conceptualized. More importantly, the way community needs and expectations could be incorporated in airport governance has been inadequately framed to address the issue of aircraft noise. This paper proposes the util-ity of adopting an integrated strategic asset management (ISAM) framework [1] to explore the dynamic nature of relationships between and airport and its surrounding area. The case of the Gold Coast Airport (OOL) operator and community stakeholders is used. This paper begins with an overview of the ISAM framework in the context of airport governance and sustainable development – as a way to find a balance between economic opportunities and societal concerns through stakeholder engagement. Next, an exploratory case study is adopted as a method to explore the noise-related complaints, complainants, and possible causes. Fol-lowing this, the paper reviews three approaches to community stakeholder engagement in Australia, Japan, and UK and discusses their implications in the con-text of OOL. The paper concludes with a contention that airport governance is likely to be much more effective with the adoption of ISAM framework than without it.

Strategies for efficient start-up of continuous biooxidation process for refractory gold ores

Strategies for efficient start-up of a continuous process for biooxidation of refractory gold ore and concentrate obtained from Hutti, Gold Mines Limited (HGML), India are discussed in this work. The biooxidation of the concentrate at high pulp density (10%) with wild strain of Thiobacillus ferrooxidans isolated from HGML mines is characterized by significant lag phase (20 days) and incomplete oxidation (35%) even after prolonged operation (60 days). Two strategies, biooxidation with concentrate adapted cells and a step leaching strategy, in which the pulp density is progressively increased from 2% to 10% were considered and the latter resulted in efficient biooxidation of concentrate. Conversion of such a process from batch to continuous operation is shown to result in complete biooxidation of the concentrate and gold extraction efficiency in excess of 90%. (C) 2002 Elsevier Science Ltd. All rights reserved.

Gold Ores Related to Shear Zones, West Santa Comba Fervenza Area (Galicia, NW Spain): A Mineralogical Study

Recent research has discovered high-grade Au ores in NNE-SSW trending shear zones in metamorphic proterozoic and palaeozoic terranes, some 40 km NW of Santiago de Compostela (NW Spain). The orebodies are bound to late-stage Hercynian structures, mainly due to brittle deformation, which are superimposed on earlier ductile shear zones, cutting through various catazonal lithologies, including ortho- and paragneisses, amphibolites, eclogites, and granites. Ore mineralogy, alteration, and ore textures define a frame whose main features are common to all prospects in the area. Main minerals are arsenopyrite and pyrite - accompanied by quartz, adularia, sericite, + (tourmaline, chlorite, carbonates, graphite), as main gangue minerals - with subordinate amounts of boulangerite, bismuthinite, kobellite, jamesonite, chalcopyrite, marcasite, galena, sphalerite, rutile, titanite, scheelite, beryl, fluorite, and minor native gold, electrum, native bismuth, fahlore, pyrrhotite, mackinawite, etc., defining a meso-catathermal paragenesis. Detailed microscopic study allows the author to propose a general descriptive scheme of textural classification for this type of ore. Most of the ores fill open spaces or veins, seal cracks or cement breccias; disseminated ores with replacement features related to alteration (mainly silicification, sericitization, and adularization) are also observed. Intensive and repeated cataclasis is a common feature of many ores, suggesting successive events of brittle deformation, hydrothermal flow, and ore precipitation. Gold may be transported and accumulated in any of these events, but tends to be concentrated in later ones. The origin of the gold ores is explained in terms of hydrotherreal discharge, associated with mainly brittle deformation and possibly related to granitic magmas, in the global tectonic frame of crustal evolution of West Galicia. The mineralogical and textural study suggests some criteria which will be of practical value for exploration and for ore processing. Ore grades can be improved by flotation of arsenopyrite. Non-conventional methods, such as pressure or bacterial leaching, may subsequently obtain a residue enriched in gold.

Notes on the treatment of gold ores.

Mode of access: Internet.

Type of housing predicts rate of readmission to hospital but not length of stay in people with schizophrenia on the Gold Coast in Queensland

Accommodation is considered to be important by institutions interested in mental health care both in Australia and internationally. Some authorities assert that no component of a community mental health system is more important than decent affordable housing. Unfortunately there has been little research in Australia into the consequences of discharging people with a primary diagnosis of schizophrenia to different types of accommodation. This paper uses archival data to investigate the outcomes for people with schizophrenia discharged to two types of accommodation. The types of accommodation chosen are the person's own home and for-profit boarding house. These two were chosen because the literature suggests that they are respectively the most and least desirable types of accommodation. Results suggest that people with schizophrenia who were discharged to boarding houses are significantly more likely to be readmitted to the psychiatric unit of Gold Coast Hospital although their length of stay in hospital is not significantly different. (author abstract)

The Effect of Temperature on the Rate of Dissolution of Gold in Cyanide Solutions which have a Constant Oxygen Content.

Since the development of cyanidation into a highly efficient process for treating gold ores, many papers have been written on its various aspects. Although, there has been much work done on it, the chemistry of the reaction is not yet completely understood.

Resembling Florida : transpacific transfer of ideas from one Gold Coast to another

Despite different political structures and planning systems, striking physical similarities exist between the tourist destinations of the Gold Coasts of Queensland and Florida. Both have been fast developing sub-tropical coastal areas, subject to massive land booms, speculation, and entrepreneurs’ grand visions throughout their history. As a result, both have become tourist destinations of international renown. Drawing on historical sources, the present research seeks to investigate the extent to which these similarities result from taking American cities as a model for newer development in Australia; in this case from transferring planning and marketing ideas from one Gold Coast to another, with the development of the Florida Gold Coast setting precedent for the development of the Queensland Gold Coast.