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By Benito Perez

Newmont Akyem mine in Ghana is committed with continuous improving results. A new environment where the price varies rapidly requires of better understanding of the deposits and the gold contained in the ore. This better understanding allows the mine planners to quick adjust and fast response to economic changes for gold price. Newmont Akyem Mine has approximately 9.4 million tons of ore in the stockpiles. Mine planers are still using average grade in all stockpiles to do a mine plan. The re-handled material is blended with the prime material coming from the mine.

Sep 1, 2017

By Thomas F. Kerr

The La Quinua mill at the Yanacocha mine in Peru has a thickened tailings storage facility that is contained entirely within an active heap leach pad. In this respect, it is unique and unprecedented in the mining industry and provides the operator, Minera Yanacocha S.R.L. (MYRSL), with certain cost, land-use and closure efficiencies. The combined design requires that the leach ore embankments retaining the tailings provide the same high level of stability and security required of major tailings dams. Contrary to standard tailings dam construction, the leach ore in these embankments is placed in thick, uncompacted lifts so that they maintain adequate permeability for leaching. The resultant loose structure makes static and dynamic liquefaction a critical issue, and the key design principle for avoiding a liquefaction related failure is to keep the ore that is saturated or very near saturated when under leach well removed from the outer faces of the embankments and contained behind large unsaturated structural shells.

Sep 14, 2009

By Sridhar Dutta

This paper point out the predictive performance of a relatively new learning model called the support vector machines (SVM) for spatial grade estimation of two grade attributes alumina and silica in a bauxite deposit of India. In developing the SVM model, it was trained with known input-output patterns of training data set which was derived by splitting the entire data set into training and prediction sets using Genetic algorithms (GA). The use of GA algorithms was made because it attempted to divide the data into two statistical similar subsets. The predictive performance of the SVM was also compared with the ordinary kriging technique using the various statistical indices including Mean Squared Error (MSE), Mean Absolute Error (MAE), Mean Error (ME) and the coefficient of determination (R2) on the prediction data set.

Sep 19, 2006

By Rob D. Morrison

The paper point out the opportunities for improved performance from Mine to Product using a range of technologies developed at the JKMRC. There are several underlying themes: Readily available computing power makes possible instrument like SPLIT, JKFrothCam and the JK/FEI Mineral Liberation Analyser, a large research project is underway applying acoustic monitoring techniques to large mills with the object being to more accurately monitor total mill load and ball load on-line. Taking advantage of these opportunities will require detailed ore characterization, good models and accurate measurement of mine and plant performance.

Sep 13, 2001

By Francisco J. Sotillo

"The paper point out the fundamentals of surface chemistry used on the design of this organic polymer, and its effect on the rheology of clayishphosphatic slurries in comparison with other available dispersants. Reducingthe viscosity of clayish slurries increases phosphate particles settling rates, and decreases value losses during desliming using gravitational forces. Also presented the improvement of desliming using centrifugal forces by achieving better separation of the ore from the slimes during cycloning."

Jul 31, 2003

By Jorge Castillo

"El presente trabajo describe las nuevas opciones tecnológicas para optimizar la recuperación de oro libre por procedimientos no convencionales, sobre la base de resultados experimentales realizados por diversos investigadoresy que están al alcance de los profesionales peruanos como alternativas de optimización metalúrgica. "

Sep 9, 2007

By N. Bournas, A. Prikhodko

A new litho-structural map was derived from the airborne geophysical survey and the 3D inversions. The newly identified faulting structures are suggested to have played a key role in the gold mineralization control. Several kimberlite targets, whose magnetic response is similar to known diamantiferous kimberlite pipes occurring within the study area, were identified from the 3D inversion results. Enhanced spectrometric data imaging and their interpretation results helped detect several uranium targets occurring within the Neoproterozoic sediments and the Eburnean pegmatites of the basement rocks.

May 1, 2008

By Sabina Strmić, Fredrik Sahlström, Siv Hjorth et al

Cobalt is critical for the green energy transition, yet the mineralogical distribution and the mechanisms of concentration of Co in different types of hydrothermal ore deposits remain poorly constrained. Here we document ore mineral assemblages from the active Fåvne and Loki’s Castle seafloor massive sulfide deposits located along the Mohns Ridge in the Norwegian Sea, and determine their whole-rock and mineral chemical compositions with a special emphasis on Co.

May 10, 2023

By Zaraí Toledo, Freddy Cáceres, John Hayes, Katherine McKiernan

Facing the rapid proliferation of informal artisanal and small-scale mining (ASM) in the 2000s, states with commodity-dependent economies pursued different strategies to enforce regulations to the activity. This article assesses the effectiveness of these strategies in increasing compliance. We leverage a view of policy effectiveness that considers the type of state-society relations a policy foster. We look at how different state-society relations impact the relevance a policy has to the subject it attempts to regulate. We argue that cooperation helps the state overcome its limitations on the knowledge of ASM and its limited institutional powers to enforce regulations alone. By learning about the activity in question and developing ties with the informal miners, the state can produce feasible regulation that is more likely to be followed.

May 10, 2023

By Rajiv Kalra

"The paper point out at evaluating the merits of oflarge geared mills versus gearless driven mills by evaluating the following factors: The capability of currently available systems in terms of power and milldiameter, efficiency in terms of overall electrical power consumed vs mechanical output power, capital cost, running costs, rooling requirements in terms of air versus water cooling and the installation and delivery time"

Sep 12, 2011

By Patrick P. M. Afenya

"The paper point out the mineralogical aspects about metals processing volcano-related gold, silver and copper ores. The copper group of metals comprises gold, cooper and silver. These metals have been considered together here because of similarities in their chemical properties. Consequently, these metals commonly form minerals with the same elements or group of elements. It is realized that the formation of minerals and final physicaland chemical states of any mineral may depend on many factors such as temperature, pressure, activity of species and pH of the fluid, mode of formation, paragenesis, geological age and post crystallization events. For the purpose of this discussion, attention will be focused on temperature as the principal factor influencing mineral formation."

Jul 31, 2003

By Raúl Castellanos

Las herramientas de modelamiento empresarial fueron diseñadas para apoyar la gestión estratégica de las empresas mineras con el objetivo de especular sobre lo sucedido con las organizaciones. En ese sentido, el presente texto señala un modelo personalizado que se ajuste a la empresa. Es decir, donde la principal función del modelador sea la “simulación”, la cual permita elegir con un menor margen de incertidumbre, la estrategia más conveniente o más rentable, aunque se complique con un número mayor de variables.

May 25, 1998

By J. Scarbrough, J. Barrett

Vector Induced Polarization arrays aim to provide unbiased and minimally low spatial sampling of artificially generated electric fields to efficiently investigate the Induced Polarization and Resistivity variations in the subsurface, generally of use in the exploration of disseminated sulphide systems beneath large covered areas.

May 1, 2008

By Daniel R. Hack

This paper point out the development of optimized routines for the processing and analysis of field data, continually building a framework for further software development. It also describes the possibilities for future development in the realm of 2D variography for surface water heat flow systems using existing proprietary and academic software packages.

Jul 17, 2000

By Edmundo Alfaro

The paper describes the thiosulfate process for gold leaching like the best non-polluting alternative to cyanide. Thiosulfate is a non-toxic lixiviant and has the ability to complex gold and silver. Copper bearing ores are not harmful for the process and does not suffer the preg-robbing phenomenon like in the case of cyanide. Nevertheless, the process is not fully developed, basically because of the poor understanding of the solution chemistry. Upon thermodynamic considerations and experimental evaluations it was found that the system is unstable; thiosulfate oxidation is unavoidable and ammonia is lost by evaporation. Measures to reduce thiosulfate oxidation include the adequate balance of ammonia and thiosulfate concentrations, adequate pH, additions of sulfite and additions of complexing agents like glycine.

Sep 12, 2005

By Guido Huarcaya

El control de costos es una actividad en la minería que se relaciona con la gestión de la empresa en diversos aspectos. En ese sentido, el presente texto plantea los modelos de control de costos empleados en dicha compañía durante el período 2004-2011, donde se reduce los diversos ratios de consumo, de forma que permanezca ubicada en el primer cuartil de las empresas mineras en costos unitarios de producción.

Sep 12, 2011

By Scott Elfen

The degree of saturation in leach facilities and waste dumps can be determined by means of this simple test equipment. A design flow rate is applied to the sample, which is equivalent to irrigation and/or the design storm event. In this sense, the paper point out that the tests were carried out on two different ore sizes from the Pierina Gold mine in Peru. The samples were remolded by using three different densities, simulating different depths within the heap. The ore was subjected to a predefined flow rate, which was equivalent to the design irrigation rate. The flow rate was increased to consider the additional effect of the design storm event during irrigation. In the future, further tests will be performed using different ores samples from operating mines and varying different parameters to help built a database and develop other useful applications from this test, such as general guidelines for maximum irrigation rates for leach facilities.

Jul 31, 2003

By T. L. Gibbs

The paper describes the role of the State in the general regulation of the mining industry in the Republic of South Africa as well to refer briefly to some modern technological aspects in South American gold mining practice. In the same way, the paper categorizes it geographical, historical, the mineral and mining laws, lease consideration and taxation, the department of mines, atomic energy board and modern practices in the gold mining industry.

Nov 20, 1969

By Yvan Guzmán, Víctor Ascuña, Federico Calisaya, Giraldo Carpio

El presente trabajo tiene como objetivo presentar el diseño de un concentrador centrífugo gravimétrico usando aire como fluido, que será usado en la recuperación del oro fino presente en los minerales auríferos. Se utiliza el modelamiento matemático fenomenológico como herramienta para el diseño del concentrador.

Sep 1, 2017

By Edmundo Alfaro

"The paper point out about on the use of ion exchange resins for adsorption of gold from ammoniacal thiosulfate solutions. In this sense, the gold can be recovered from ammonium thiosulfate solutions with strong base resins. The amount of gold loaded onto the resin in a batch process is a function of gold concentration in solution, amount of resin, volume of solution, copper and competing ions concentration in solution. Thiosulfate concentration in leaching solution has influence on gold loadings onto resins; in contrast, ammonia concentration in solutions has no influence on gold loadings. Gold seems to be loaded onto the resin preferentially over copper - thiosulfatecomplexes and also over thiosulfate ions. Polythionate ions strongly compete with gold and copper thiosulfate complexes for resin sites. This causes reduction on gold and copper recoveries from the leaching solutions. Even more, polythionates are produced in leaching solutions when thiosulfate is oxidized by the action of both copper and oxygen. "

Jul 31, 2003