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The Northland region of New Zealand has a complex geological history which has long been the subject of considerable controversy. Small mineral deposits have been discovered in the past, and some have been mined. Except for aggregates and very high quality china clay, mining is virtually nonexistent at present. Mercury mining is proposed from small deposits in the Kaeo area. Intensive exploration for epithermal precious metals deposits in the past seven years, combined with some recent geological mapping undertaken by the Geological Survey and University thesis students has added greatly to an understanding of Northland's geology. Mapping of the Whangaroa-Kaikohe map sheet at a scale of 1:100 000 by Brown and Laurenson Limited has enabled new geological information to be collated for the first time since 1961, when the last geological map was published. The 'Northland Allochthon' is now observed to be a series of four or more thrust sheets each containing predictable formations. High angle faulting contemporaneous with overthrusting has modified the thrust sheets, and established a series of horsts and grabens. The Pirau Fault is considered to be a major earth fracture.

Jan 1, 1987

By R J. Merchant

The Hauraki goldfield is located east of Auckland in the North Island of New Zealand. It includes Great Barrier Island, the Coromandel Peninsula and the Coromandel and Kaimai Ranges as far south as the town of Te Aroha and south east to Te Puke. It has a total north-south extent of about 180 km and an area of 3000 km2. The goldfield is the most productive in New Zealand, and while production at present is negligible, the area has undergone continuous exploration over the last seven years.

Jan 1, 1984

By Nye P. B, Fisher N. H

At the second Empire Mining and Metallurgical Congress held in 1927, the Empire Council of Mining and Metallurgical Institutions was formed and it was proposed that the Council take steps to prepare a "Review of the Mineral Resources and Industries of the Empire." At the third congress in 1930, it was resolved that the proposal to institute the review should be submitted to the Imperial Conference held in 1930. This was done, and the Minerals Committee, of the Imperial Economic Committee compiled, an interimreport which was based on statistics of imports and exports, and did not consider resources and consumption.In 1942 the Institution of Mining and Metallurgy, London, wrote to the Empire Council and stated that it was desirable that the Council should be in a position to take part in decisions affecting the future of the mining and metallurgical industries. The Council communicated with the constituent Institutions regarding the nominations of two members then in England. Subsequently the Mining, Geological and Metallurgical ,Institute of India prepared a review of the mineral resources and industries of India and their post-war development, and the Empire Council forwarded a copy to the Australasian Institute of Mining and Metallurgy and asked if that Institute would submit a review on simjIar lines for Australia. The Australasian Institute arranged that the Australian review should be prepared by...

Jan 1, 1946

By D Giurco

As part of global systems of mineral production and consumption, the Australian minerals sector is facing sustainability challenges across technological, social, ecological, economic and governance domains, as well as between local, national and global scales. To ensure that the Australian minerals sector progresses towards sustainability, it is imperative to understand the possible ways in which AustraliaÆs mineral resources could support sustainable futures. A significant research gap exists between the complex nature of questions concerning minerals sustainability and the reductionist methods available to deal with them. This paper argues the need for broader, more integrated approaches to questions concerning minerals sustainability, which can address multiple human perspectives, complex and æmessyÆ patterns and processes across multiple organisational, temporal and geographical scales and whole systems of mineral production and consumption. To inform the development of a new approach to minerals sustainability, this work reviews the contemporary understanding of the Australian minerals sustainability problematic, from the perspective of the Australian minerals sector (Minerals Council of Australia), the Australian research sector (Mudd 2007a, 2007b; Mudd and Ward 2008) and a multi-scale international project (MMSD 2002). This review shows the focus of current responses to the minerals sustainability problematic, identifies the need for an integrated approach to questions of minerals sustainability and addresses how different approaches are informed by underlying and unarticulated assumptions about the tolerability of tradeoffs between different societal goals, the treatment of uncertainty and the application of different conceptual geographical, organisational, temporal and life cycle scales to define the minerals sustainability problematic. The Mineral Resources Landscape proposed, offers an expanded conceptualisation of minerals sustainability, to link minerals production and consumption in an integrated assessment across the entire minerals supply chain, connecting social, ecological, technological, economic and governance domains across local, national and global scales. The key leverage points governing change in the Mineral Resources Landscape are identified as: the material source, extraction and production technologies, level of service and value, and consumption patterns. Mapping the key challenges facing the minerals sector, as identified in the review herein, indicates that the boundaries defining traditional conceptualisations of minerals sustainability focus on the material source and technology and ignore two very key drivers of the Mineral Resources Landscape û the æservicesÆ minerals offer to society and the æconsumption trendsÆ which assimilate these services into society. Understanding these overlooked aspects of the Mineral Resources Landscape, along with the conventional areas of focus, is essential for identifying the Australian minerals sector as a provider of sustainable mineral services. This insight prompts a reconsideration of the role of minerals services and consumption trends, together with the role of the material source and technology in shaping change and the emergence of sustainable systems of Australian minerals production and consumption, across multiple scales and domains.

Jan 1, 2009

By Glaessner M. F

The island chains of the Western Pacific (Fig. 1), on account of their related origin, and the similarity of the rocks that compose them, constitute in the main a most homogeneous mineral province. They lie in a complex "mobile" zone of the earth's crust, that formed a geosynclinal area separating the continental margins of Australia and South-Eastern Asia (the so-called Sundaland) from each other, and from the margin of the Pacific Ocean proper (FIg. 2). The whole region was drowned at the close of the Ice Age, as a result of the rise of sea-level that accompanied the melting of the great ice caps in the polar regions, leaving only the higher portions as islands and peninsulas, many of them separated only by shallow seas or "shelves."The geosyncline was infilled with Mesozoic and Tertiary sediments that have undergone varying intensities of folding and metamorphism, and has been subject to intermittent periods of volcanic activity, continuing into the present. Midway between the two continental margins there is a narrow belt of pronounced negative gravity anomalies, with an extraordinary S-shaped convolution in the vicinity of the Banda Sea and Celebes, that marks the core of this unstable region. The folding within the "mobile" zonetrends parallel to it, so that the islands in its vicinity, which are regions elevated by folding, are all elongated in the strike direction of the folds. This explains not only the linear shape of Sumatra and Java, but the arc of islands enclosing the Banda Sea, and the peculiar shape of Celebes.Parallel to the belt of negative anomalies, at a close remove from it, is the line of Recent, or active volcanoes, that extends along the whole length of Sumatra and Java...

Jan 1, 1947

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada . The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analysed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

By King D, Dickinson S. B, Matheson R. S

Commencing in 1956, Rio TInto Australian Exploration Pty Limited in association with Electrolytic Zinc Co of Australasia, Limited, has been carrying out a mineral prospecting program in North-West Tasmania over an area of about 4000 square miles.The program has comprised extensive airborne geophysical surveys, detailed geological mapping, ground geophysical and geochemical investigations. Out of the wealth of new data, and the examination of previous records, has emerged a new structural concept of regional ore control and distribution in North-West Tasmania. This roncept stems from the discovery of an ancient 'fossil' rift valley (graben), named the Owen Rift Valley, along which are located the major mines of the area and numerous well-known prospects. The known mines and prospects from north to south include Mt Bischoff (tin); the Pinnacles (zinc, lead, ropper); the Chester (pyrites); Rosebery-Hercules (lead, zinc, ropper, silver, gold); Mt Tyndall (lead, ropper, zinc); Comstock and Tasman (copper, lead, zinc); Mt Lyell (copper, pyrites, gold); Mt Jukes and Mt Darwin (ropper). The identification of the West Coast (Owen Conglomerate) Range as a fossil rift valley is due to Or B Campana, who carried out extensive geological mapping and interpretation work, and who, with S B Dickinson, are the senior authors of this paper.S B Dickinson, who introduced B Campana to the geological problems of West Tasmania, had previously investigated the Mt Lyell and Rosebery mining fIeld, to which reference is made in this work.D King assisted in the regional mapping and in providing numerous data on the mineral distribution of the area.R S Matheson rontributed to the fmdings on ore emplacement and rontrol in the discussions held on this subject. They are accordingly included as joint authors of this paper.Credit is also due to E McCarthy, who interpreted the geophysical results, and to J H Rattigan, who compiled the preliminary geological maps from published documents and by photo-geological methods.G Hall and V H Cottle, of the Electrolytic Zinc Co in Rosebery, provided invaluable geological data and suggestions in the course of the survey, and made a constructive criticism of the manuscript of this work. The airborne geophysical survey carried out by the Adastra-Hunting Geophysics Ltd company, furnished useful data which substantiated many of the fIndings on the stratigraphic and structural relationship. The Mines Department of Tasmania and S W Carey, Professor of Geology at the University of Tasmania, were instrumental in initiating the regional survey and provided the published and unpublished geological literature on the area.The authors also wish to acknowledge the invaluable assistance received from the Mt Lyell Mining and Railway Co in Queenstown, which made available the more recent geological and mining documents rompiled by M L Wade and M Solomon.

Jan 1, 1994

The Kangiara mine is located within the Middle to Upper Silurian Hawkins Volcanics of the Douro Group near Yass, New South Wales. The deposit is a po1ymetallic type within a rhyolitic tuff.The ore minerals comprise pyrite, sphalerite, botryoidal sphalerite, galena, chalcopyrite, marcasite, tetrahedrite, bismuthinite, bismuth, silver, electrum, chalcocite, covellite, and digenite. The gangue minerals are quartz, barite, calcite, and the host rock. Locally sericite occurs.Several distinct ore types can be recognized, mainly on the basis of their macroscopic textural appearance, and it is inferred from these general features that the mineralization had a submarine volcanic-sedimentary origin similar to that of the Kuroko deposits in Japan.

Jan 1, 1976

By King D, Dickinson S. B, Matheson R. S

Graham Hall and V. M. Cottle (Rosebery, Tas.) : In their paper on "The Mineralized Rift Valleys of Tasmania", Campana, Dickinson, King and Matheson have summarized a wealth of data from many sources. In proposing the new concept of a rift valley structure, they claim to have found a new guide to regional ore control and distribution in North-west Tasmania.Although the authors acknowledge suggestions made by us prior to publication of the pa:per, we are still at variance with their conclusions. We are not convinced that a rift valley structure exist~d when the Ordovician conglomerate was deposited. We are unable to find evidence for Cambrian deposition in a rift valley or reason to project the structure to embrace Hercules, Rosebery, and "possibly" Mt Bischoff.That the Great Lyell Fault (the authors' Owen Rift Fault) is a promising place to look for ore is not a new idea, but the existence of important ore deposits away from the structure reveals its inability to provide an adequate explanation of regional mineral distribution. A well-known structure that does have an influence on ore deposition is not discussed by the authors.STRUCTURAL CONSIDERATIONSThe great thickness of coarse unsorted Ordovician conglomerate lying in an elongate but narrow belt of country is presented as evidence of its deposition centrally within a rift valley, the position-of which is now said to be outlined by resistant slabs of the conglomerate. The marginal shears of the rift are said to show up well along the edges of the conglomerate.

Jan 1, 1959

By Van Deventer J S J

The first step in the design of a process to treat a possible economic precious metal deposit should be an examination of the mineralogy of the ore. Using this and other initial tests, the extractive metallurgist can design a process to treat the ore. In the field of precious metal metallurgy, little emphasis is placed on the mineralogical information available to the metallurgist. The information is of far more use to the geologist and the mining engineer. Diagnostic leaching was designed to open up the field of mineralogical analysis to the metallurgist. When a mineralogist looks at the deportment of gold in an ore, he is usually looking for an element which is present in parts per million, so that errors in sampling are multiplied dramatically. Diagnostic leaching offers a cheap, simple, practical alternative. In order to determine with which minerals the desired precious metal is associated, a specific mineral is first eliminated using a selective oxidative leach, and cyanidation is used to extract the precious metal (in this case gold and silver) liberated by the destruction of this mineral. The precious metal extracted can be measured in solution to give a fairly accurate record of the amount of the precious metal associated with that mineral. Furthermore, the residue from this first stage can be subjected to another selective acid leach, and the process repeated. The procedure can be varied to suit the mineralogy of the matrix material. At the end of this diagnostic leach the metallurgist is left with a complete record of the deportment of the precious metal. He can now use this information to design a metallurgical flowsheet to treat the ore. Diagnostic leaching is thus an analytical tool which can be used by the metallurgist not only to examine new ores, but also to look at problems occurring at existing plants. The procedure is not only limited to ores and residues but in fact can deal with any type of intermediary product that occurs on a plant. The information gained from analysing an intermediary product can give a useful indication of how well a unit process is working, eg flotation, roasting, etc.

Jan 1, 1992

The Mineralogical Researches of Gold Ores and Technological Products at Operating Factory in Olympiada Mine (Russia)

Sep 13, 2010

The mineralogy, textures, and genetic significance of a silver-rich siderite vein and an apparently co-genetic galena vein from the South mine, Broken Hill are discussed.Both veins cut sharply across the Main Lode Horizon and appear to be coeval with thc A.B.H. Consols lode.The minerals of thc siderite vein apparently result from the preferential leaching of silver from Main Lode Horizon ore with a demonstrable "breakdown series" commencing with tetrahedrite, passing through silver sulpho-salts, and ending with simple binary compounds or with elemental silver.The siderite vein has been deposited by metahydrothermal fluids along the lines of Schneiderhohn's "secondary hydrothermal" mineralization.

Jan 1, 1968

Several factors contributing to the loss of fibre during treatment are a function of the paragenesis of the veins. The occurrence, of magnetite from the cap rock within the veins prevents complete fiberization. There is a marked similarity between these veins and those in the Koegas-Westerberg area of South Africa.INTRODUCTIONAn investigation of the mineralogy of the Wittenoom Gorge crocidolite veins was undertaken in the latter part of 1962 at the request of the Colonial Sugar Refining Co. Ltd. It was anticipated that such a study might reveal the cause or causes of the lack of recovery of some asbestos during beneficiation. Some interesting features of the mineralogy and paragenesis of the crocidolite veins become apparent, but it is emphasized that the investigation is far from complete, as the study did not extend to the field occurrence.The samples examined were selected from the mill and from the untreated ore.GEOLOGICAL SETTINGWittenoom Gorge is situated on the Fortescue River in the Hammersley Ranges of Western Australia and is one of several gorges in these ranges, on the sides of which 'crocidoIite asbestos is known to occur. The Hammersley, Ranges consist essentially of a series of quartzites, shales, ferruginous quartzites and dolomites. These' rocks are part of the Nullagine Formation (Proterozoic) and are usually either horizontal or gently folded. In some 'areas small beds of riebeckite as well as crocidolite are known to occur interbedded in the sequence.Riebeckite is a monoclinic amphibole, the formula of which may be stated as Na2Fe2"Fe2" (OH) 2Si8O22, and crocidolite is a fibrous variety of this mineral. This formula...

Jan 1, 1963

The Mineralogy and Reactivity of Pyrrhotite from Selected Nickel Ore Deposits and its Effect on Flotation Performance

Sep 13, 2010

In the Massif du Sud ophiolite complex platinum group elements occur predominantly as ultrafine-grained inclusions of rutheniridosmine, laurite and iridosmine. These form primary inclusions less than 5 to 10 um in diameter within chromite in podiform chromitite fringed by dunite, and emplaced subsequent to solidification of the host harzburgite. There is no specific association with trace inclusions of transition metal sulphides. The crystallization of then: Ir. Os and Ru minerals may have occurred concomitant with hromite, perhaps related to more reducing conditions produced by crystallization of the chromite. The Ir, Os. and Ru show pronounced fractionation from Pd, Pt and Rh expected to be also present in the mantle source rock. The dunite shows evidence of metasomatic origin from adjoining harzburgite, and the possibility of selective crystallization of the Ir sub-group elements suggests that Pd, Pt and Rh may have been transported elsewhere.

Jan 1, 1989

By McGhie R. R

The general structural features and the principal mineral relationships of the Black Star ore body, Mount Isa, Queensland, have been described in several previously published papers. But particular reference may be made to the work of Grondijs and Schouten, whose examination of over 200 polished sections revealed some remarkable features in the process of ore deposition. The observations by the present authors are based upon the study of a smaller ·set of specimens complementary to those examined by Grondijs and Schouten and are intended to elaborate certain aspects of the mineral relationships, more particularly those affecting the ore-dressing processes.The work described applies to the primary sulphide ore only, and to the present milling practice of fine-grinding and selective flotation.GEOLOGICAL FEATURESThe Black Star is one of several economic mineral concentrations in the Mount Isa series of thinly bedded carbonaceous shales, which are considered to be of preCambrian age. The nlineralization is apparently connected with pegmatite intrustions located within some miles of the ore bodies, and has been Gontrolled in the main by major folding of the shales and by a shear system which follows approximately the strike and dip of the beds. The detailed "The investigations described in this paper were made in the Metallurgy Department, University of Melbourne, where the senior author was formerly Senior Lecturer in Mining and Metallurgy. A report on a section of the work was submitted by the junior author as a thesis requIred by the University of Queensland.

Jan 1, 1939

The copper deposits at Pernatty Lagoon are predominately djurleite-digenite bodies beneath the permanent water table, and chrysocolla-atacamite-malachite above the permanent water table. The minerals havebeen deposited as sheets, lobes, and pods in zones suggestive of permeability channels or permeability basius with respect to groundwater circulation.Pyrite is deposited in the form of framboids, which reflects its biogenic origin. Copper-iron sulphides deposit by replacement of pre-existent pyrite, and rarely by direct deposition. The latter mode of formation results in complex crustification bandings of chalcopyrite, bornite, sulphur rich bornites, digenite, and blue remaining covellites. The copper-iron sulphides appear to reequilibrate under constrained oxidation, resulting in an iron depletion and associated copper enrichment, the final product of which is a djurleite-digenite assemblage and associated with goethite. Where copper mineralization/ host rock relationships have rendered the rocks entirely impermeable to post ore groundwater movement, then the copper-iron sulphides are preserved as the ore assemblages.Minor and trace minerals observed include sphalerite, carrollite, galena, wittichenite, and possibly tetrahedrite in the primary ores. In the oxidized ores cllprite, tenorite, and trace brochantite have been found.

Jan 1, 1976

While the new Minister of Economic Development sends his apologies at being unable to speak at this Conference, I am delighted to present on his behalf. The Ministry of Economic Development is not only responsible for managing the Crown mineral estate, but also for developing initiatives and policies to promote regional economic development and for managing the GovernmentÆs broader economic development strategy. IÆd like to talk to you today about the critical links that need to exist between these three areas.   I am going to start with a question for all of you. What do these towns have in common? +        Waiuku, +        Thames, +        New Plymouth, +        Nelson, +        Greymouth, +        Arrowtown, +        Reefton, +        Palmerston, and +        Dunedin.   The answer is minerals. These towns were nearly all founded on the back of minerals and mining. In the case of Greymouth it was gold that brought the people to the mouth of the Grey River and it is coal that sustains the town.   In 1870 the town of Shortland had 20 000 people, 90 hotels and was twice the size of Auckland. We now know Shortland as Thames, and of course Auckland is considerably larger. One wonders whether the good folk of Shortland suffered from ætraffic jamsÆ with 90 pubs to navigate between. Gold mining in the Aorere River near Collingwood led early entrepreneurs to develop the land surrounding Nelson as a food basket to sustain the mining population. Nelson is still thriving on this legacy today. The town of Palmerston was founded in 1862 as a stopping point for gold miners heading into central Otago. The gold rush made Dunedin New ZealandÆs first highly industrialised city. Reefton on the West Coast was the first town in New Zealand to have electric lights and in the recent past we were wondering whoÆd be left to turn them off. New Plymouth, and Waiuku are still known as energy and mining centres.   By contrast once thriving towns like Capleston, Canvastown and Blackball are just names on a map now, and at the extreme you have places like Waiuta which has been reclaimed by the West Coast forest. Queenstown was built off the back of the gold rush, but by 1900 with the gold gone, only 190 people lived there yet Queenstown has managed to rebuild itself thanks to some other stunning natural assets. These examples help illustrate three key points that I am sure will each be extensively linked with our minerals and mining industries. First, NZÆs development and that of its regions has been, and continues to be, inextricably linked with our minerals and mining industries.   Second, things change. Sectors, regions and countries must continually adapt and improve if the are to avoid the fate of the Waiutas of this world. And third, the development challenges faced by NZ and its mining industry in the 21st century are vastly more complex than in the past. Governments and industry alike must balance and respond to a range of domestic and international environmental, cultural, economic and other interests and considerations. If you thought of your industry as æjust digging holes in the groundÆ then you may as well simply stick your head in one!

Jan 1, 2005

There is no doubt that the mining sector is considered to be the backbone of many countries. Furthermore, it has played an important role in the prosperity of nations, whether developed or developing. Saudi Arabia is one of these countries that has a large variety of metallic and non-metallic mineral resources that range in size and value occurrences of limited potential to deposits large enough to sustain profitable exploitation. Therefore, the Saudi government needs to reinforce the capacity of the sectoral institutions to better regulate and promote the sustainable development of the sector. The ability to overcome the administrative and legal complications that constrain private sector participation in the minerals sector, through new mining code which will streamline the procedures for obtaining licenses and will add more predictability and transparency to the application process, are proposed for increasing the sustainable development. This paper will outline how the Saudi government is tackling the major challenges that face the minerals industry. This paper provides the background to the Saudi Arabian mineral sector and its industrial base. Finally, the paper identifies the problems and constraints that face the minerals sector in Saudi Arabia and provides an assessment of the effects of government policies and planning efforts in the minerals sector, particularly during the period of the development plans which started in 1970.

Jan 1, 2009