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THE Broken Hill mining field, approximately 31 miles in length, is at present being exploited by seven companies, viz. : North Broken Hill Limited, Junction North Broken Hill No Liability, Broken Hill Proprietary Block 14 Company, Broken Hill ProprietaryCompany Limited, Sulphide Corporation Limited, Broken Hill South Limited, and Zinc Corporation Limited.The variation in size and shape of the ore-bodies in the mines of these companies, together with the many alterations in pitch and dip, necessitates differences in methods of mining, each company working out its problem in its own particular way.In the matter of chute construction for the handling of the ore broken in the stopes, each mine belonging to the above companies has adopted a style particularly its own, though it may be said that one or two of the types approximate very closely to each other, slight minor differences only being noticed in the design. It is the purpose of this paper to give a brief description of the principal types of chutes now in use in th,e various mines on the field, and in doing so they may roughly be classified into three groups, viz:1. Bulk Chutes, 2. Circular Chutes, 3. Square-set Chutes.The Bulk type of chute is used in the North and British mines of the North Broken Hill Limited, the Central and Junction mines of the Sulphide Corporation, the South Blocks mine of the Zinc Corporation, and the Block 14 mine.The Circular type of chute is used by the Broken Hill South mine and the South Blocks mine.The Square-set chute is used in the Proprietary mine, the Junction North mine, and occasionally in other mines where the square set method of mining is a necessity, and more particularly as mullock passes.

Jan 1, 1925

By Elbridge W. Gresseth

Rock deformational structures in a deep mine were analyzed by petrofabric techniques to learn (1) the relative magnitude and direction of the principal stresses involved in tectonic deformations prior to mining, (2) the preferred orientation of rock planar discontinuities which define rock anistropy prior to mining, and (3) the relationship of mining-induced rock failure to inherent rock stresses and inherent rock anisotropy. Rock fabric elements used for petrofabric analysis consisted of bedding planes, faults, joints, fractures, foliation, sericite plane (001), quartz axis [0001], quartz deformation lamellae, and microfractures. Structures and structural symmetries from different areas within the mine and from different scales of observation were compared to learn the nature of rock anisotropy and the orientation of the principal stresses defined by rock deformations. Analysis of such fabric as regional and macroscopic faults, b-c joints, quartz [0001], sericite (001), and microfractures, indicate that during the epochs of tectonic deformation, the maximum and minimum principal stresses were horizontally oriented and acted along northwest and northeast axes, respectively. This condition of regional stress appears to have continued during folding and the associated period of faulting. The most recent tectonic deformation represents a rotation of the minimum principal stresses into a vertical position, as shown by the development of a tensile joint system, quartz deformation lamellae, and microfractures. Good interscale correlation and statistical homogeneity of tectonic fabric indicate a stress field homogeneity in this area during tectonic deformation. Rock physical anisotropy is genetically associated with tectonic fabric and consists of preferentially oriented planar discontinuities intersecting along a nearly vertical axis. The mining-induced deformations were correlated with the inherent rock anisotropy which either directly controls or greatly affects their development. This phase of rock deformation shows a greater degree of stress field heterogeneity than was the case with tectonic deformations This is explained as a result of nonconfinement afforded by underground openings and the increase in ground stresses due to mining activity"

Jan 1, 1968

Floor heave events in underground mining often happen suddenly and cause risk to workers and equipment. Reducing the risk of floor heave must be addressed in mining layout design. To improve that design one must understand the significant parameters that are correlated to the occurrence of floor heave. To accomplish that goal, researchers from the National Institute for Occupational Safety and Health (NIOSH) completed a numerical study using FLAC3D, taking advantage of its strain softening and ubiquitous joint capabilities to better simulate the floor heave and caving mechanisms involved at an actual mine site.

Jan 7, 2020

By A. Rajan

"Drawing upon the experiences of a gold extraction plant startup in the Southern Pacific, this paper will describe the importance of the commissioning phases to the project outcomes to achieve early target production despite an overall time compression to attain full plant production. Some of the highlights of the paper include: impact of roles played by the Owner’s construction and operations representatives during project commissioning, the formation of a capable and competent “Mod Squad,” availability of trained operating personnel, control over work priorities and the scope of work needed to bring the plant to safe initial operations. The commissioning team comprised subject matter experts skilled in process technology supported by “generalists” thoroughly conversant in overall plant operations. The merits of a structured team approach to brainstorm and resolve commissioning challenges as opposed to direction from individual subject matter experts is discussed. IntroductionStartup or commissioning is a unique period in the life of a project. Each stage of a project-exploration, feasibility, design, construction, commissioning, initial operations and continuing operations-requires special talents, know-how, and practices. Each stage makes particular demands of the people involved. Initial operations are no exception.Having experienced the 1997 startup phases of oxide and sulfide facilities for a gold extraction plant at a remote island in the Southern Pacific, I can attest to the many challenges and rewards. Commissioning for both facilities was extremely successful and brought the entire project on line well ahead of the targeted completion dates. Using this specific project as an example, this paper will highlight some of the key features of project commissioning. In this paper, the term “pre-commissioning” denotes all activities that lead to mechanical completion; “commissioning” occurs when feed is introduced; and “initial operations” are defined as the duration when operations accepts the system/facility and takes over."

Jan 1, 2000

By M. Mikolás, L. Pomothy, K. Špakovská, M. Vanek

"Enterprises are faced with increasing economic competition and managers are obliged to look for methods that will ensure a competitive edge in their companies’ markets. These methods include managerial concepts that employ common sense and are low cost. One of these approaches is the KAIZEN methodology, of Japanese origin; kaizen means continuous improvement (CI) when translated. A mining company, despite some of its idiosyncrasies, is just an enterprise where the application of KAIZEN can be advantageous. The company investigated, OKD, is the only domestic producer of hard coal in the Czech Republic and operates four mines that produce 11 Mt of coal annually. The OKD management team opted for KAIZEN as their principal method of continuous quality improvement. This paper suggests ideas for development and application of processes that provide for continuing improvement of production and management. The authors have taken the OKD Company to be their benchmark in the field of mining activities. The paper also focuses on possible difficulties accompanying the introduction of CI sustainable methods. Three years of application of CI methods has increased the income of the company by almost US$38.1 million, which provides a strong argument for continued application."

Jan 1, 2015

A calibration of the Frantz isodynamic magnetic separator relates the current in the electromagnet and the transverse slope of the chute to the specific susceptibility at which separation is being effected. In addition to providing a rapid measure of the specific susceptibility of minerals and composite grains, the calibration provides a guide to operation of the Frantz isodynamic separator for mineral separation, and to the nature of composite grains. The most sensitive magnetic separation is obtained by using the highest practicable current and transverse slope, and the lowest practicable longitudinal slope.INTRODUCTIONProbably all minerals have a magnetic susceptibility measurable by sensitive techniques. However, magnetic separation between minerals which have low but different specific susceptibilities, and which for many purposes are considered essentially non-magnetic, has only become practicable with the development of the Frantz isodynamic separator.The construction and principle of this highly sensitive separator has been described by S. G. Frantz as an appendix to a description by 'Gaudin and Spedden (1943) of its application to the separation of sulphides constituting mill products.Various publications (e.g. Hess, 1949, Hutton, 1952) refer to its use in separating the mineral constituents of rocks, ores, and unconsolidated sands.As used in this study the Frantz isodynamic separator consists of a vibrating chute mounted centrally between the pole pieces of an electromagnet (Fig. 1). This unit may be inclined in any direction by the universal mounting, and the electromagnet current is continuously adjustable from 0 to 1·5 amperes.

Jan 1, 1957

By Rudolph Emmel

THE mines operated by the South American Development Co. are located in the Zaruma mining district of southwestern Ecuador. They are near the old mining town of Zaruma, which is the only important city in the canton of the same name. The district is situated in the upper end of a valley lying between two spurs of the Cordillera, one of which may be considered the Coast Range and the other an intermediate range. The mining camp proper, known as Portovelo, and the plant are 2.4 km. south of Zaruma, on the north bank of the Amarillo River, a tributary of the Tumbes River, which flows southwestward through Peru to the Pacific. Portovelo is difficult of access; it is reached from Guayaquil by means of river steamers and muleback. Embarking at Guayaquil, the route is down the Guayas River, across the Jambeli Canal, and up the Santa Rosa River to Santa Rosa, a distance of 177 km. From Santa Rosa, the road or trail follows the Santa Rosa River, then across the summit of the Coast Range into Portovelo, a distance of 74 km.-a two-day trip on muleback. The mining property of the South American Development Co. comprises 297 lode claims and 142 placer claims. The combined lode claims cover an area, roughly rectangular in shape, 9000 m. long from north to south by 4000 m. wide; the northern edge of the rectangle is about 3000 m. north of the central plaza of Zaruma. Mineral lands in Ecuador are held by virtue of an annual tax per claim paid to the central government, no surface rights being included.

Jan 1, 1925

Detachment of Particles from Bubbles in a Stirred Cell

Sep 13, 2010

Preparation of MgO Nano-Particles with Magnesite

Sep 13, 2010

By M. Maier

Geographic Information Systems (GIS) has evolved into a powerful tool for analyzing spatial and attribute data in many industries including mining. Modern field data collection techniques add another dimension to the use of data in the field and enhance the utilization of GIS for mining applications. This discussion will review how field data is collected and how office data and maps can be taken into the field to be analyzed and verified using pen-based computers and differentially corrected GPS.

Jan 1, 2001

By M Passmore, N Poznik

Olympic Dam is a world-class deposit and is unquestionably one of the most geologically, structurally and texturally complex orebodies in the world. As development advances into the Southern Mine Area (SMA) the geological understanding is rapidly evolving as underground drill rigs are prioritised to provide the additional data necessary to convert Indicated and Inferred Resources into Measured Resources. The SMA represents approximately 70 per cent of Olympic Dam’s total resource and is significantly more complex when compared to the Northern Mine Area with respect to the diverse nature and origin of lithotypes, rock mass characteristics and the extent of major structures controlling primary mineralisation trends.Recent mine development into the central SMA has been impacted by a major structural gouge zone. Sound geological interpretation allowed mine geologists to successfully integrate their local understanding of the distribution of lithotypes with critical geotechnical data, chiefly rock quality designation (RQD), to delineate and better predict this major structural gouge zone. As a direct result, development rates improved whilst also increasing awareness for the importance of sound geological interpretation utilising all available data. In order to maximise predictability across all systems in place through the mining geology value chain, the integration of geological and geotechnical data in a geotechnical RQD block model provides an additional tool to assist in preventative solutions for complex problems to achieve a proactive mining environment.This paper details the methods used to build the RQD block model, the geostatistical estimation parameters, 3D geotechnical domain wireframes, challenges regarding legacy approaches, and collection of geotechnical information and incorporating/linking geotechnical data with geological features, including the use of grade and lithotype domains. Although the geotechnical block model proved difficult and complex to construct, the resultant product has seen successful integration of geological and geotechnical data into mine planning providing higher resolution of critical parameters for local mining areas.CITATION:Clark, J M, Passmore, M and Poznik, N, 2017. Olympic Dam rock quality designation model – an integrated approach, in Proceedings Tenth International Mining Geology Conference 2017, pp 27–36 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By Wm. F. Netzeband

"The mode of ore occurrence and the methods and costs of mining at one of the zinc-lead mines in the Tri-State zinc and lead district, Oklahoma, are presented in this paper for the information of mine operators in other districts.No. 2 mine property was acquired by lease in 1918 after some 30 holes had been drilled and a shaft had been sunk to the 305-foot level by the first lessees. After acquisition of the lease, the present operating company drilled a rich ore body on the 260-foot level and in 1920 started sinking two shafts. Production was begun late in 1921, and the mine has been operated more or less continuously to the present time.The mill has a capacity of 400 tons in 10 hours, the usual length of the mill shift in the district.The geology of Mine No. 2 is very similar to that of Mine No. 13 except that the Cherokee shale is thicker, ranging from 80 to 160 feet, and all the formations are correspondingly deeper, the Short Creek oolite horizon here being at a depth of about 300 feet. The oolite has not been found on this property, but the lime comes in at about the level at which the oolite should appear.The ore deposits of Mine No. 2 occur in the brecciated and bowlder ground above the Short Creek oolite. The main or 260-foot level is about 40 feet above the oolite horizon, and the lower or 300-foot level is immediately above it.The ore deposition is controlled by a zone of shearing and fracturing, and the mineable areas are divided into two distinct runs which have a northwest trend with a lean or practically barren area dividing them. This characteristic has controlled the mining to a large extent, for it enables the mine superintendent to locate the large pillars in lean ore and leave only small pillars in the richer ore. Figure 1 shows the outlines of the ore body and the pillars.The ore on the main level occurs disseminated throughout the jasperoid breccia as patches or lenses in the jasperoid, or cementing massive bowlders of jasperoid breccia and chert. The ore of the lower level is more of the bowlder type than that on the main level and occurs chiefly cementing the bowlders but also with some disseminated ore in the jasperoid breccia.The gangue minerals are jasperoid breccia, chert, and dolomite. Calcite is found in minor quantities. Sphalerite is the principal ore mineral; galena is found only in minor quantities around the edges of the ore body. When galena is encountered in this ore body, the limit of the ore can be expected.The exploration and estimation of ore reserves at Mine No. 2 are similar in many respects to the methods used at Mine No. 1.4After the mine was opened up and the general character of the ore deposit had been determined, drilling operations were concentrated along the trend of the shear zone. Later drilling has proved what appears to be a parallel shear zone or an offset of the zone now being mined."

May 1, 1929

By R. Schulz, K. King

Concentrating Line 6 just went down again. The control room operator checks the graphic display. Only one piece of equipment shows an alarm. Clicking on the ball mill icon, he discovers the culprit was the low flow lube switch. The flow looks okay now, but it is the third time this week the switch has stopped the line. Maintenance is called, the switch replaced and the line is up running again. Sending the right person to the right spot immediately can save hundreds of hours of downtime every year. This paper discusses the principles behind implementing smart First-Out Fault Detection to dramatically reduce equipment downtime in new, or existing control system architectures. Methodologies are presented to maximize the system benefits, while minimizing development costs. Case histories are presented for a number of successful implementations in mineral processing plants.

Jan 1, 2001

By F. A. Rutledge

The Batesville district in north central Arkansas is one of the important sources of manganese ore and ferruginous manganese ore in the United States, with a history of production dating back to 1849. From studies by the Federal Geological Survey, it was recognized that the district probably still contains substantial reserves of low-grade ore. It was natural, therefore, that the deposits in this area should be among the first investigated by the Bureau of Mines under the Strategic Materials Act of June 1939, by which the Bureau was authorized to explore domestic deposits of strategic minerals, at that time designated as those of antimony, chromium, manganese, mercury, nickel, tin, and tungsten. The field work of the Bureau of Mines in the Batesville district was done in two distinct phases. Under project 308, active from August 1940 to June 1941, carbonate-oxide ores were investigated at five separate areas in which 100 trenches, test pits, shafts, and edits aggregating 4,364 linear feet were excavated and 839 samples were taken and assayed. Under project 323, in progress from February 1941 to January 1942, wad deposits were explored at 10 separate areas by 408 prospect shafts, churn-drill holes, and bucket-drill holes aggregating 23,680 linear feet from which 285 samples were taken and assayed. Processes for beneficiating the wad ores were investigated at ore-testing laboratories of the Bureau of Mines.

Jan 1, 1952

By John E. Tilton

The ability of companies and countries to mine copper and other mineral commodities competitively and in the process to generate new wealth depends on their mineral endowment. Chile, for example, produces and exports copper because it is well endowed with high-quality, low-cost deposits. This production creates wealth that benefits mining companies and their stockholders, the government, local communities, as well as copper consumers around the world. The widespread perception that mineral endowment must largely determine competitiveness, or what economists call comparative advantage, must be true at any particularly moment. Countries with abundant reserves must be competitive. This follows from the definition of reserves — the quantity of a mineral commodity found in discovered deposits that are profitable to exploit under current conditions. As a result, it is a tautology and not particularly interesting. The important question is what causes reserves to change over time, producing in the process new wealth and shifts in competitiveness?

Jan 1, 2003

By Van Sint JanM., M. Prudencio

ABSTRACT We report the results of a model-testing program to evaluate the strength characteristics of non-persistent joints. We describe the conditions under which new tensile cracks generate and propagate to connect existing joints so that the rock mass becomes fractured into several blocks, leading to a low strength. The strength of some models was equal to that along a single joint through the full sample length. In models with two joint sets, failure took place along a composite plane, partly sliding along a discontinuous joint and shearing through the intervening intact block of rock, or else by rotation and sliding of the blocks. This last failure mode could also lead to very low model strength. ZUSAMMENFASSUNG Dieser Bericht beschreibt die Ergebnisse von Versuchen mit Modellfelsmassen um den Einfluâ von unterbrochenen Rissen in ihrer Widerstandsfähigkeit zu untersuchen. Es werden die Umstände beschrieben unter denen neue Zugrisse entstehen, sich verbreiten, sich mit bestehenden Rissen verbinden und die Felsmasse in mehrere Felsblöcke zerlegen und zu einer kleinen Widerstandsfestigkeit führen. Der Widerstand einiger Versuchskörper entsprach der Festigkeit eines Risses der die ganze Länge des Versuchskörpers überquert.Versuchkörper mit zwei Rißfamilien versagten unter einer zusammegesetzten Ebene, zum Teil mit Verschiebungen nach unterbrochenen Rißebenen die sich durch Schnittversagen intakter Felsblöcke verbinden, und zum Teil durch Drehungen und Verschiebungen einzelner Felsblöcke. Die letzte Versagunsart kann zu einer stark verminderten Widerstansfähigkeit führen. RÉSUMÉ Nous présentons les résultats de quelques essais fait sur des modèles évaluant les caractéristiques de résistance des fractures discontinues. Nous décrivons les conditions sous lesquelles des nouvelles fissures de traction peuvent s’engendrer et se propager pour faire la connection avec des fractures existantes, de façon que le rocher se fracture en plusieurs blocs, menant à une résistance réduite. La résistance de quelques modèles fut égale a celle d’une fracture traversant toute la longueur du modèle. Pour les modèles ayant deux ensembles de fractures, la rupture a eu lieu sur une surface mixte, causée d’une part, par le glissement sur une fracture discontinue et d’autre part, par la rupture à travers le pont de matériel intact; ou bien par rotation et glissement des blocs. Cette dernière façon de rupture peut aussi aboutir à une très faible résistance des modèles.

Jan 1, 2003

The Effect of Molecular Weight on the Adsorption and Efficacy of Polysaccharide Depressants

Sep 13, 2010

By Thomas E. Marshall, Michael Dunn, L. J. Prosser, Anthony T. Iannacchione

During the past few years, the Pittsburgh Research Laboratory of the National Institute for Occupational Safety and Health (NIOSH) examined and characterized conditions at a majority of the underground stone mines in the United States. Observations at these mines revealed a limited degree of roof monitoring beyond visual inspection and sounding. When monitors are used, they typically require the miner to measure movement at the roof. If conditions are unstable, the mine rmay be in a hazardous situation while recording data. Based on this scenario, researchers surmised that a simple, inexpensive monitor with the capability of recording data at a distance from the mine roof would be a safer way to gain the information. Additionally, more widespread use of monitors could potentially lead to better understanding of roof movement in general. A monitor to meet this need was designed, tested, and subsequently improved as experience was gained in its’ use at a number of underground stone mines. The Roof Monitoring Safety System (RMSS) can provide an initial indication of movement in roof beams. By understanding and measuring roof movement in underground mines, the potential for injuries and fatalities to mine workers from falls of ground can be reduced. Also, officials at a mine with a history of data are better prepared to make a decision on remedial actions in the event of ground falls. This paper will outline the evolution of the RMSS and how it can be used in a comprehensive proactive ground control safety program. Also included is a case history describing how the RMSS was used in an evaluation of the effectiveness of a mechanical impact scaling machine at an operating limestone mine.

Australia is not capitalizing on the raw gems and precious minerals that it produces in abundance. In particular, there is an unrealised value for diamonds due to lack of processing after mining. Australia could enhance the value of its raw jewellery products by developing and integrated jewellery industry. For instance, initiation of a diamond industry would require training programmes to educate people in the requisite skills, such as diamond sorting, cleaving, sawing, bruting and polishing. Equally important would be the training of people in design jewellery, manufacturing, and appropriate diamond grading and sales techniques. Future technological advances in diamond processing will decide where the major diamond processing centres of the world will be. Australia, for a relatively small investment, could develop a highly productive diamond processing capacity using the new technology available. Australia's geographical position, and advanced banking and communication facilities provide the potential for this country to become a major trading centre for diamonds. KEYWORDS: Argyle Diamond Mine, Diamonds, Diamond Production, Diamond Sorting, Jewellery Industry

Jan 1, 1989

By A. Alonso, J. Daubenspeck

In the nickel extraction process at Nicaro, Cuba, dried and ground nickel bearing laterites are reduced at 1300-1400F in multiple-hearth furnaces. Nickel is leached from the reduced ore by aeration in an aqueous solution of ammonium carbonate. Nickel carbonate is precipitated from the liquor and calcined to yield nickel oxide. The following are the more important modifications of the Nicaro process since plant rehabilitation and expansion. Ten percent increase in tonnage was achieved without decreasing the fineness of the ore by minor mechanical modifications of the grinding plant. Another five percent increase in tonnage was attained by intentionally overloading the ore prepration and leaching circuits in an effort to control cobalt extraction. Modifications at the sintering plant allowed it to handle the entire output of the expanded plant. A fifty percent increase in leach liquor cooling facilities alone provided an increase in nickel production of five percent. Stronger fresh leach liquor for increased nickel washing efficiency was obtained through improved distribution of water to the ammonia absorption towers. Advantage was taken of the reduced calcine's capability to precipitate cobalt, and modifications in the leach liquor circulation provided controlled cobalt solubility with minimum harm to nickel extraction. Several process changes at the drying plant brought about a ten percent reduction in the fuel oil consumption at this pint. Controlled air addition to the reduction furnaces' upper hearths burned formerly wasted combustibles thereby reducing oil consumption by twenty percent. The nickel extraction process successfully emplayed on the extensive but lowgrade lateritic ores of Eastern Cuba at the U. S. Government owned Nicaro plant, has been previously described in various publications. The large mine and plant operated by the Nickel Processing Corporation, located on the northeastern shore of Oriente Province, have been recently expanded to a yearly capacity of about 50 million pounds of nickel. Essentially, the operation involves open pit mining of a limonite-serpentine ore mixture containing 1.3 to 1.4 percent nickel and 34 to 38 percent iron. The comparatively lumpy, wet (25 to 30 percent moisture) ore is first dried and ground prior to chemical treatment, to which the entire 7,000 tons per day feed must be subjected. In the initial chemical action the dried and ground ore is reduced with carbon manoxide and hydrogen at 1300-1400° in multiple-hearth furnaces. The resulting metallic nickel is selectively leached from the reduced calcine by aeration in an

Jan 1, 1961