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The only simple sulphide mineral of antimony of importance is stibnite, SbS3, containing 71·8% antimony when pure. It is lead-grey, has a densityof 4·5 to 4·6 and melts at 546°C. It is both friable and sectile (Hardness 2 on Moh's scale) and, as a result, slimes very readily during milling.It is commonly associated with pyrite and arsenopyrite other minerals occurring with stibnite in minor quantities are chalcopyrite, galena, and scheelite. The latter mineral occurs in sufficient quantity at the Yellow Pine Mine, Stibnfte, Idaho, to justify the production of a scheelite concentrate.Stibnite mayor may not contain gold. Other minerals such as pyrite or arsenopyrite may contain gold. At Wiluna at the main mine nearly all the gold is asociated with arsenopyrite the stibnite being almost free from gold, whilst at the Moonlight Mine both arsenopyrite and stibnite carry gold.The mineral, tetrahedrite, which is a complex sulphide of copper and antimony; must also be considered an economic source of these two metals.Part of the copper may be replaced by iron, zinc; silver; or mercury, whilst part of the antimony is often replaced by arsenic.CLASSIFICATION OF ANTIMONIAL GOLD ORESFor the purposes of this paper antimonial gold ores may be conveniently classified as follows: CLASS 1. Ores from which a satisfactory gold extraction may be obtained by fine grinding, followed by cyanidation and which contain insufficient antimony to justify tIie production of an antimonial concentrate.CLASS 2. (a) Ores in which a satisfactory gold extraction may be obtained by straight cyanidation, but which contain sufficient antimony to justify the production of an antimonial concentrate.CLASS 2. (b) Ores from which the gold extraction by straight cyanidation is unsatisfactory. This type of ore requires the production of an antimonial concentrate for reasons which will be considered later.In deciding whether an ore belongs to class 1 or 2 (a) it should be remembered that the normal price of star antimony is about £1.00 sterling per ton and that the value of each 1% of antimony recoverable as metal is worth about £1 per ton.The antimony content of antimonial gold ores is liable to be considerably...

Jan 1, 1944

Some 800 analyses for Cu, Zn, Pb, Ag, Fe, S, CaO, MgO, C02, Si02 and Al203 were used to examine the elemental constitution of the Mount Isa ores, and, for comparison, those of the Northern Leases area.Lead: zinc relations show little order from sample to sample, but means of large zones (Le. individual orebodies) show a highly linear inverse relationship. Lead: silver ratios are fairly constant from sample to sample, and means show a highly linear direct relationship.Sulphide sulphur appears to be related to carbonate and alumina abundance, sulphur decreasing systematically with increase in the ratio CO2:AI203. In all graphs involving members of the group CO2-A203-S the lead-zinc and copper ores conform to the same simple trends, confirming that the two ore types and their host rocks are genetically closely related. The earlier deduction of a volcanic-sedimentary origin for the sulphides of the Black Star orebodies appears compatible with present findings.On the basis of such an origin, the pattern of sulphide occurrence and mineralogy in the Mount Isa district is possibly related to the configuration f the upper surface of the "Eastern Creek Volcanics", the facies patterns of the overlying sedimentary rocks, and to the oldest faults affecting the two.INTRODUCTIONStanton (1962) described and interpreted the chemical constitution of the Black Star No. 2 lead-zinc and the 650750 copper orebodies at Mount Isa. The investigation has now been extended to the other principal orebodies of the area.The earlier study showed that the host rocks of the two adjacent Black Star orebodies were constitutionally closely related, and suggested that this was probably due to their original formation in contiguous zones of sedimentation. On this basis the silica-dolomite of the copper ore appeared to represent the slightly more shoreward, "limey" member, probably a fairly massive algal calcareous sediment laid...

Jan 1, 1963

By R H. Sibson

The gold province of Otago occupies an area of upwarped basement, the Otago Schist, comprising predominantly quartzofeldspathic and volcanogenic metasediments. This assemblage is the product of collisional tectonic deformation and associated metamorphism, mainly to lower greenschist facies, during the Rangitata Orogeny (200-100 Ma). Historically this region has produced 240 tonnes of gold, 4% (10 t.) of which was from the mining of Cretaceous goldquartz mineralised vein systems. Auriferous vein systems in the Otago Schist are mainly hosted within NW trending normal fault-fracture arrays, however NW trending reverse fault-hosted vein systems also occur. We propose that the Late Cretaceous-mid Tertiary Otago Schist structure represents a regional anticlinorium containing flexural folds of at least two wavelengths. The anticlinorium structure has been quantified by determining variations in angular discordance between schistosity and the Otago Peneplain, a Late Cretaceous-mid Tertiary erosion surface covering most of the Otago district. A structural model for the evolution of the post-collisional anticlinorium requires the cooling surficial zone (carapace) of a retrograding metamorphic belt to behave as an elastic lid. Erosion of topographic load on the carapace drove isostatic uplift, which was greatest in the tectonically thickened core of the orogen. In this way differential uplift produced flexural deformation in the elastic carapace, expressed as a large scale arching of the orogenic belt. Flexure created tangential longitudinal strains in the outer-arc, leading to extension and the formation of mineralised normal faults. These structures are separated by a neutral surface from shortening and associated mineralised reverse faults in the inner-arc. Our structural model predicts that the distribution of auriferous lodes should be localised about zones of maximum flexural curvature, where the tangential longitudinal strains are highest. As a result, NW-SE hinge regions separating schistosity dip domains in the Otago gold province may have new found significance as potential exploration targets.

Jan 1, 1995

There is a significant amount of historical mining and exploration information available. This information is often distributed throughout a number of reports or plans, available from a variety of sources, and in many differing formats. The ability to capture paper-based historical information in a modem digital format provides mining and exploration companies with valuable information that can be used in a number of ways; for example, reassessments of exploration or mining work previously undertaken, or used in conjunction with current exploration information.   The purpose of this paper is threefold. Firstly, to present the paper-based historical information; highlighting some of the problems encountered, solutions to those problems, and any assumptions used. Secondly, to present the historical data in digital format, and demonstrate the tools available to analyse geological and associated information, and finally, to illustrate some of the potential future applications of the information, including mining optimisation, mine design and scheduling.   The Glenorchy scheelite/gold prospect has been used as an example. Within the overall prospect two smaller areas were selected. The Mount McIntosh and surrounding areas, focuses on exploration and surface excavation information. The Mount Judah area (State and Kelly-Taylor workings) focuses on underground mining and exploration information.  

Jan 1, 2001

Every automatic citizen is an automatic recipient of a miner's right under the present Mining Act (Chapter 195), but this alone does not entitle any automatic citizen to mine for minerals on any land, even his customary group's land. Without complying with requirements of the Mining Act, any automatic citizen who engages in mining solely on the basis of a miner's right would be mining illegally. He would also be engaged in illegal mining if he mines on customary or other non-government land. Even if mining is legally pursued by an automatic citizen, he does not acquire ownership of minerals without first making the required royalty payments to the State.

Jan 1, 1991

By D Craw

Formation of gold-bearing veins in Otago Schist was intimately linked to the structural evolution of the schist belt. The currently-exploited Macraes gold deposit formed in a regional scale shear zone during latemetamorphic uplift of the schist belt. Further exploration for this type of deposit will be facilitated by an increased understanding of the late-metamorphic structural evolution of the schist belt. To this end, a three-dimensional cross section through the Otago Schist has been drawn using structural data gathered at outcrops in a 20 - 40 km wide transect across central Otago. This is the first continuous detailed structural section to be drawn through the belt. The section spans an area from Textural Zone 1 metagreywacke of the Torlesse terrane in the northeast through TZ 4 schist in the central region and across the Caples-Torlesse boundary to Textural Zone 3 schist of the Caples terrane in the southwest. Two different late-metamorphic structural generations are identified in this section: the long-recognised Manorburn Generation, and a new æPoolburn GenerationÆ. The location of the Caples-Torlesse boundary has been refined on this transect by field mapping combined with whole rock geochemistry.

Jan 1, 2001

By B B. Beamish

Long-hole directional drilling for in-seam exploration was introduced to New Zealand at Huntly West Mine in 1989. Following the success of this initial drilling program the Coal Corporation of New Zealand (CoaICorp) purchased its own drilling equipment and proceeded to adopt the technique with in-housetraining. From July 1991 to September 1992 a total of 15 455 metres was drilled at Huntly West Mine. During this period several modifications were made to the drilling technology to suit the ground conditions. The resulting interpretations of the drill information enabled reliable seam definition to be incorporated in mine planning. Since January 1993, the technique has been transferred to the Huntly East Mine to assist with seam definition for the planned development westwards under the Waikato River. The benefits of this drilling technique to coal mine planning are now well documented in Australia and New Zealand as well as other overseas countries. The possibilities of adapting the long-hole drilling technique to hard rock applications has been illustrated recently with successful cross-measure drilling at Huntly East Mine.

Jan 1, 1993

The material presented in this paper describes experimental work to determine the effect of variations in suction nozzle design upon inlet flow conditions. Four entrance profile shapes were examined under controlled conditions of slurry flow and it was found that the straight ended nozzles had consistently higher entrance losses than the straight taper or the ellipse, and that the circular arc profile nozzles were the most efficient. Subordinate considerations were the measurement of the quantities and the forces involved.As the work progressed, three distinct phases in the pattern of flow were apparent and the static pressures in each were carefully examined. An inlet zone was found to be unstable in changing boundary conditions, a transition zone was largely independent of slurry density and in a zone of stability the pressures were found to be directly related to the characteristics of the flowing pulp. In this zone pressure measurements were reproducible within ± 2 per cent regardless of changing boundary conditions.The effect of varying the "1" parameter of nozzles with a part circular entrance profile was examined and it was found that flow conditions approaching the ideal were obtained when the radius of curvature was between 0·40 and 0·550.

Jan 1, 1966

The author summarizes and extends the relevant results of papers previously published by various authors and presents these results in chart form. The charts are used to demonstrate the theory on a hypothetical mine.INTRODUCTIONRecently a series of articles have dealt with leakage in a mine ventilation system and the problem of its reduction.Theories were developed by Peascod and Keane (1955) for the combined effect of flow in the airways and leakage through the porous barrier between the intake and return of an ideal mine. Later Keane and Peascoa. (1956) extended these ideas to the use of an underground booster fan in increasing the face ventilation and showed how to determine the water gauge and location of the most efficient underground fan.These articles were based on the assumption that Atkin:son's formula:P = R Q2 (1)gave the relation between the pressure drop P lb'/sq. ft., the quantity, Q kilocusecs, flowing in the mine airways and the total resistance, R Atkinsons, to air flow offered by the mine roadway. An Atkinson is defined as a resistance such that 1 kilocusec of air flows due to a pressure drop of 1Ib.jsq. ft. However for conditions prevailing in most mines a more :appropriate relation is that postulated by Reynolds and others (Lamb, 1953) :P=R Qn (2)where n has some value slightly less than 2. It should be noted that Atkinsons may not be used as units when n is not equal to 2.

Jan 1, 1958

Based on relative CO2, N2, and 3He contents, geothermal systems of the Taupo Volcanic Zone, TVZ, can be subdivided into two major groups: arc-type systems, associated with andesitic magmatism along the eastern boundary of the TVZ, and rift-type systems over its western parts. The highly increased N2/3He, CO2/3He and CO2/Cl ratios of the former are ascribed to entrainment of large proportions of volatiles of subducted, marine sedimentary origin. The largely rhyolitic, rift-type magmas are assumed to have formed from volatile-depleted, residual melts. Correlations of Cl and CO2 with heat contents suggest that formation of the two types of source magmas involves mixing of two end member components: a low-volatile melt with a heat/Cl ratio of 25 Ml/mol (0.7 MJ/g), and a low Cl vapor with a heat/CO2 ratio of 5 Ml/mol. On the basis of these values, the heat associated with andesitic magmas is found to be carried in close to equal parts by both vapor and melt; for the rhyolitic melts the proportion contributed from the vapor is only about 2%. The heat/He ratios of the rhyolitic source magmas for the rift-type geothermal discharges from the TVZ of 0.12¦0.05 Ml/pmol is within the range of 0.05 to 0.2 Ml/pmol of the upper mantle. The higher heat/3He ratios for the arc-related magmas of 0.4¦0.2 Ml/pmol are likely to be due to the high proportions of heat carried in the form of a separate, low 3He vapor phase derived largely from subducted sediments.

Jan 1, 1995

By G H. Clark

Batu Hijau is a porphyry copper-gold deposit located onSumbawa Island in the western Banda Arc of Indonesia. The deposit has been evaluated from 54 000 m of drilling in 105 diamond drill holes over a surface area of 1.2 km2 and to a depth of 1000 m below surface (412 m below sea level). A provisional plan is being evaluated to mine 642 million tonnes at an average grade of 0.61% Cu and 0.55 g/t Au (variable cut-off) from an open pit in the higher grade portion of the resource.   The deposit is associated with a calc-alkaline intrusive complex that was emplaced in a thick sequence of andesitic pyroclastic rocks. The oldest and most widespread intrusion is porphyritic to medium-grained, equigranular, quartz hornblende diorite. At Batu Hijau the western diorite contact zone was intruded by two phases of tonalite. The older tonalite is a stock increasing from 200 m diameter at surface to 500 m at sea level. It consists of quartz, plagioclase and hornblende phenocrysts set in a groundmass of similar composition. A younger tonalite intrudes the tonalite stock, quartz and plagioclase phenocrysts are more abundant and it has a finer groundmass than the older tonalite. Brecciation occurs near the older tonalite contacts but there are no breccia pipes or late-stage features such as pebbledykes or postmineralisation intrusive rocks.   Hydrothermal alteration of Old Tonalite and adjacent rocks is centred on the Old Tonalite and is zoned from a core of pervasive potassic alteration grading to an outer propylitic halo. At depth a propylitic assemblage is developed in the low grade core in the Old Tonalite. Phyllic alteration, late stage and mainly fracture controlled, overprints both potassic and inner propylytic zones. Intermediate argillic alteration overprinting is widespread, particularly on the eastern side of the hydrothermal system, where advanced argillic alteration overlies argillic alteration.   Ore grade mineralisation is cylindrical in shape, up to 800 m in diameter, and is centred on the Old Tonalite. A high grade shell (>0.75% Cu) forms an upward tapering cone in and around the Old Tonalite and reaches the surface in the centre of the deposit. Lower in the shell >l g/t Au and >2 g/t Ag accompany >1% Cu. Below 75 m above sea level mineralisation in the Old Tonalite rapidly decreases as a weakly mineralised core develops, but the limb continues to contain mineralisation to at least 412 m below sea level. Fracture and vein-controlled chalcopyrite and bornite are the dominant hypogene copper minerals and are the hosts for most of the gold mineralisation. Gold occurs free and in the lattice of the copper sulphides, and has been observed in quartz.   Weathering, especially where argillic alteration is developed, has produced a strongly leached cap, up to 147 m thick, below which is an irregular copper enriched supergene zone. Where leaching is not developed, such as over the centre of the deposit, an irregular oxide zone and a weakly developed supergene zone may be present.

Jan 1, 1995

Water quality standards for some of the substances likely to be discharged to natural waters by the mining industry are discussed. After briefly examining how uses of water can be affected by discharges, standards for suspended solids and turbidity, pH, and toxic materials are considered. Heavy metals are examined in some detail because of recent public concern regarding their discharge. Caution is given in connection with their analysis at the very low concentrations required for management of natural waters. Finally, the issues of what constitutes a water right concentration compliance breach, and the appropriateness of biological monitoring as a condition on a water right are raised.

Jan 1, 1986

At Appin colliery, geological structural analyses and investigations of roof conditions suggest roof failure may be attributed to vectorial stresses acting on underground openings, and inducing movement along inherent discontinuities in the surrounding rocks. Certain complex joint and fracture patterns tend to exhibit the effect of this movement resulting often in local deterioration in natural support.The following conclusions are drawn.1. Roof failure is related to the inherent nature of the roof rocks, the presence of mechanical discontinuities, and the vectorial stresses imposed upon it.2. Roof failure is not necessarily related to the statistically most prominent jointing.3. Colliery development approximately parallel to the direction of the statistically most prominent jointing sometimes results in favourable roof conditions.4. The maximum principal stress is the resultant of those vectorial stresses acting upon a mine opening and may be inferred from roof adjustments to those stresses after mining.5. Statistical analyses of jointing in the mine workings can provide clues to the tectonic force or forces which have been regionally or locally influential.6. There is a probable relationship between mining induced fracturing, jointing, and micro-fractures in quartz grains, within the sediments of the mine roof.

Jan 1, 1970

A numerical method for discriminating between replacement and sedimentary processes is applied to a folded stratiform sulphide occurrence. It is shown that numerical treatment of chemical analyses from a single diamond drill hole allowed a rapid assignment of the ore to the syngenetic sedimentary class and thereby enabled a revision of the evaluation program concerned with consequent reduction in costs.

Jan 1, 1973

By Sparrow G. J

The effect of polyelectrolyte flocculants on the de-watering of a tailing suspension of very fine clay was investigated.Sedimentation and filtration experiments were carried out in the labqratory to characterise the de-watering properties of the tailing. The results were used to calculate the effect of flocculant additions on the drainage and vaporation components of the de-watering of a clay suspension ponded on to a sand drainage bed.A flocculant increased the drainage rate, but decreased the volume of water that could be removed by drainage leaving more water to be lost by evaporation.The sorptivity values measured in the laboratory were used in the de-watering equation previously established for the tailing to estimate the effect of flocculant additions on the time required to de-water the suspension from 18.2 to 60 per cent solids w/w. The calculated de-watering times were found to increase or decrease depending on the volume of water removed by drainage and the prevailing evaporation rate.

Jan 1, 1980

The State of New South Wales is highly favoured in having vast deposits of coal adjacent to and within easy reach of the coastal Ports. Not only is the quality of the fuel generally superior to any found in the other States, but it is greater in extent than in any other part of the Continent. For interesting and reliable details of the history of the discovery of coal, the geology of the coal bearing strata, analysis of the various coals and other valuable data, the readers are referred to the book recently issued by the New South Wales Government, entitled The Mineral Resources of New South Wales, by Edward F. Pittman, A.R.S.M., etc., by the direction of the Hon. T. L. Fegan, Minister for Mines. The mining community is indebted to the Minister for having had published the most valuable condensed record of the mineral resources of the State extant.For the purposes of this paper we will only give such a general description of the coal fields as will make it intelligible in connection with the subject of the coal mining in the State of New South Wales.

Jan 1, 1904

Development of Process for Beneficiation of Low-Grade Iron Ore Samples from Orissa, India The paper deals with the results of characterisation and beneficiations studies undertaken on two low-grade Indian iron ore samples (IO-1 and IO-2) with a view to develop process for beneficiation of composite of the two samples to a high-grade concentrate, suitable for iron making through pelletisation. Indian iron ores contain relatively high iron but cost effective reduction of alumina within the specified limits has been a challenging task. Characterisation of the samples revealed the ore to be laminated and fine grained with hematite as the major mineral. Clay is the dominating gangue in most of the ore pieces followed by silica. Occasionally goethite and quartz/jasper were recorded. Clay occurs either as patches within the hematite mass or as cavity/fracture fillings. Liberation studies on the representative samples crushed to 2 mm indicated that around 95 per cent of the grains are liberated below 105 micron. Beneficiation of the two individual samples and their composite based on gravity and magnetic separation techniques resulted in products with varying yield and grade of the products. The effects of various process parameters were studied. Granulometry of the feed was observed to be important for improving quality of concentrate. The results of bench-scale studies were validated through pilot-scale continuous trials. Based on the studies undertaken a suitable process was developed for beneficiation of the composite sample, comprising 60 per cent IO-1 and 40 per cent IO-2, to a high-grade product assaying over 65 per cent Fe and material balance was computed. A commercial plant for beneficiation of low-grade iron ore to produce DRI pellet grade concentrate is proposed to be installed.

Sep 13, 2010

By M Carter

The Great South Basin is located beneath the northwest part of the Campbell Plateau, a+broad, nearly level, triangular shaped submarine platform, southeast of the South Island of New Zealand. It encompasses an area of 77 700 square kilometres and contains a sequence of Cretaceous to Tertiary sedimentary rocks which are up to 6000 metres thick near the centre of the basin (Shirley, 1983). The western boundary of the basin is adjacent to the steep Aucklands Slope. In the+ north it merges with the Canterbury Basin and to the south onlaps against the Pukaki Rise, a basement high. The eastern margin of the basin is bounded by the northeast - southwest trending steep linear Antipodes Scarp. In the extreme south the Antipodes Scarp curves westward and joins the north trending Aucklands Slope. The Campbell Plateau is dominated by tensional tectonics. The Antipodes Scarp represents a major region of transcurrent faulting initiated by Cretaceous rotation within the Campbell Plateau. Later movements are associated with the Alpine Fault of the South Island (Sandford, 1980; Anderton, Holloway, Engstrom, Ahmad and Chong, 1982).

Jan 1, 1983

FREQUENTLY the Survey Department is caIled upon to estimate the quantity of material in various dumps, dams piles, etc... and in the carrying out of this work various methods may be employed.The method used will vary according to the particular case in hand, and factors such as accessibility of the top of the dump, steepness of its sides, height, and the condition of the material to be estimated. A certain amount of "give and take" must be adopted in the treatment of small local cavities and mounds.In all cases it is desirable that the surveys made should be tied on to the lease surveys for the purpose of location, and that all levels should be reduced to the mine datum. It is also desirable to obtain levels of the original surface before deposition of the material to be estimated. If these have not been obtained beforehand, levels and transfers round the top will be the next best. If space is availabIe, flat surface is chosen as a site for the dump, etc. This is of the utmost importance in those cases where the material will have to be...

Jan 1, 1925

The use of solid state detector and radioisotope x-ray source for x-ray fluorescence analysis is illustrated by analysis for iron, copper, zinc, tin, and lead in about 700 samples taken from Australian mineral process streams. Limits of detection based on counting statistics (3 standard deviations) range from 0·001 to 0·004 per cent by weight element. The analysis accuracy was usualIy between 2 to 10 per cent (rms) of the mean element concentration and was determined by comparison with assays supplied by mineral companies. In most cases the main cause of error appears to be due to this assay and not the x-ray fluorescence technique.Some potential fields of application of solid state detector and radioisotope x-ray source for analyses in the mineral industry are indicated.

Jan 1, 1974