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By J. R. Carr

A crucial concern when implementing computer algorithms for geostatistical analyses on microcomputers is speed of execution. Kriging, in particular, typically relies on a Gauss elimination algorithm to solve for weights. Because such an algorithm is required for each estimate, the solution for weights can result in very slow program execution speed on a microcomputer. One approach to enhancing the efficiency of Gauss elimination is demonstrated herein. The upper triangle plus diagonal of the intersample covariance matrix is used in a modified banded Gauss elimination algorithm. Results show that such an algorithm yields approximately a two-fold reduction in execution time for kriging when the number of nearest neighbors used for estimation is large.

Jan 1, 1990

By Gordon A. Gross

Banded siliceous manganese-iron bearing sediments recognized as distinctive facies of Algoma type iron-formation constitute low grade resources of manganese in many countries. Manganiferous facies associated with oxide and carbonate facies of iron-formation have iron to manganese ratios ranging from 0.2 to 2 and commonly about one. Manganiferous facies up to 30 meters thick occurring separately or with other iron-formation facies are associated with cherts, carbonates, shales, turbidites, tuffs and lavas. Primary cherty manganiferous facies and their gondite metamorphic equivalents represent significant manganese resources and are protores for higher grade deposits derived by secondary enrichment processes.

Jan 1, 1982

By Charles Will Wright

ITALY is by- far the poorest in mineral resources of the so-called great pou7ers of Europe. Before the World War this shortage was not so serious as the essential minerals that could not be mined domestically at a profit were bought in the world markets. In those days tourist trade and remittances from Italians abroad helped to provide Italy with foreign exchange. During the World War, when certain mineral products were scarce and when prices rose in some instances to several times normal, the Italian Government began to regulate consumption and imports. It was not until later, when the Fascist regime established the corporate state, that Italy seriously considered adopting a of self-sufficiency. Private industry was grouped under separate corporations, for the principal industries; including mining and metallurgy and the heads of the large producing companies, became members of these corporations. Industrialists were thus able to regulate their own affairs and to advise the Government as to the measures necessary to meet domestic or foreign trade demands upon their industry. Labor was or-

Jan 1, 1939

By P York

The study commenced in October 2012, to understand the basic ecology of the spotted-tailed quoll (Dasyurus maculatus) and to confirm whether the species utilise previously mined land on the Mt Owen mine site that was rehabilitated in 1996 to 2011, as part of their home range. The spotted-tailed quoll is a widely distributed marsupial carnivore that is listed as rare or threatened in every state in which it occurs. The species is a forest-dependent marsupial carnivore that occupies a wide range of habitat types (Long and Nelson, 2004).The first part of the study involved trapping a spotted-tailed quoll and fitting the individual with a combined global positioning system / ultra high frequency (GPS/UHF) radio-transmitter collar (Telemetry Solution – Quantum 4000E). The benefit of the GPS/UHF collar is that it records locations (or fixes) at intervals programmed by the user. The UHF component allows the researcher to locate the individual at a frequent interval, and the Quantum 4000E also has a remote download function, enabling the GPS data stored in the collar to be wirelessly transmitted between the collar and researcher. The benefit of this new technology is that the animal does not need to be repeatedly captured to retrieve the GPS data.Daytime searches are also undertaken using the UHF receiver to locate the individual and locations of daytime denning and latrine sites. The location of each den site is recorded using a hand-held GPS. Data downloaded from the GPS collar is then imported and mapped using computer software program ARCGIS (geographic information system), to overlay the data points onto aerial photography.Results demonstrate that threatened species will utilise rehabilitation areas post mining. The data presented will be used to develop a greater understanding of threatened species ecology in and around rehabilitated areas, which will assist in the planning and design of native forest rehabilitation areas.CITATION:York, P, 2014. Mt Owen Mine spotted-tailed quoll study, in Proceedings Life-of-Mine 2014 , pp 591–596 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By C. P. Lazzara, R. A. Franks, G. F. Friel, J. C. Edwards, J. J. Opferman

A series of four coal combustion experiments was conducted at the National Institute for Occupational Safety and Health's (NIOSH) Pittsburgh Research Laboratory (PRL) in the Safety Research Coal Mine (SRCM) to evaluate the response of fire sensors to a small 0.61 m square smoldering coal fire which transitions to flaming combustion in the presence of diesel emissions. An optical path smoke sensor alarmed earlier than a point type diffusion mode ionization smoke sensor which alarmed prior to a CO alert value of 5 PPM above ambient. The presence of steady state diesel emissions resulted in a decrease in the optical smoke sensor analog output voltage signal by less than 1.4 pct for the three coal fire experiments in which a diesel engine was operating, whereas the ionization smoke sensor output decreased between 10.8 and 26.7 pct after the initial surge of the diesel engine. A commercial diesel discriminating fire sensor did not alarm for a fire in the one experiment for which it was used. The results of the experiments demonstrated that an optical path smoke sensor might be used to detect a coal fire under the experimental conditions considered of starting a diesel engine followed by a slowly developing coal fire.

By R. R. Klimpel

This paper describes four new families of flotation products which are currently being introduced at the industrial level. A brief summary of the chemical basis behind each product family will be given. This is then followed by a selection of flotation examples which illustrate the more important use characteristics that have been observed to date. It is becoming more apparent with further testing that these four new product families can offer both technical and economic advantages to the industrial flotation process operator.

Jan 1, 1992

By William Cochran

Data on the cost and quantity available were developed for rutile (TiO2), which is potentially recoverable as a byproduct at sand-washing plants in the Southeastern States of Alabama, Georgia, North Carolina, and South Carolina. Baaed on 1969 production data, an estimated 4,300 tons of rutile could be recovered annually from plants that process more than 25,000 tons of sand per year. Rutile prices at which this resource would be available ranged upward from $262 per ton, compared with the current market value of $185 per ton.

Jan 1, 1972

By David S. Young

All pigments and extenders or fillers whether organic or inorganic fall into the following broad general classes: I. Colored II.-White III. Black IV. Metallic A pigment- is any particulate matter that is essentially insoluble and chemically unaffected by the media into which it is dispersed. According to this very broad definition, colored pigments, white pigments, fillers, extenders, and functional pigments would all be included. The particulate size range would also be quite broad ranging from very fine colloidal particles (~0.01µ) to relatively coarse particles (~100.0µ). This broad definition is usually subdivided into more practical divisions which tend to relate the classification of the pigment to its primary function in the system in which it is used. Hence, the word extender implies that its major purpose may be to extend the system.

Jan 1, 1985

By W. N. Hamilton

Industrial minerals are plentiful in Alberta. Although exi ting in variety and in quantity, they constitute a minor segment of the province's mineral industry, which is based on oil and gas. In 1983 Alberta led all the other provinces in value of mineral production with a total of $22,2 18 million, 62 per cent of the total for Canada. Of Alberta's total, $22 million or about 3 per cent came from the indu trial minerals. Nearly two-third of this production is accounted for by sulphur, which is actually a by-product of the oil and ga industry. Alberta ranked third among the province in industrial minerals production for 1983, with about 20 per cent of the national total.

Jan 1, 1984

By Zhongning Shi, Ramana G. Reddy, Min Li, Zhaowen Wang

Electrodeposition of cobalt from cobalt tetrafluoroborate (Co(BF4)2) was investigated using 1- butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) ionic liquid. The experiments were conducted at 353 K. Chronoamperometry experiments confirm that the electrodeposition of cobalt on tungsten electrode proceeds via three-dimensional instantaneous nucleation with diffusion-controlled growth process. The average diffusion coefficient of Co(II) was found to be 7.5 × 10-8 cm2s-1 at 353 K, which is in good agreement with the estimated value from cyclic voltammetry. The electrochemical deposit was characterized using SEM-EDS and XRD methods. The SEM image shows formation of a dense and compact deposit at - 0.75 V. The EDS and XRD analysis confirm that the obtained deposit is pure cobalt metal.

Jan 1, 2015

Maps To Accompany Bulletin 418

Jan 1, 1941

By Alfred L. Ransome

GOLD output in Alaska in 1950, following a 2-year decline, increased to the highest point since 1942. Tills unexpected gain in production of the Territory's greatest value commodity was largely responsible for the increase in the over-all value of mineral output in the Territory to $17,852,000 from $15,549,000 in 1949. Although coal continued to rank second to gold in value of output, production was slightly less than the record production of 1949. The mining of platinum continued to be an important factor in the mineral industry, with production of crude platinum metals exceeding that of 1949. The output of lead was three times the 1949 production, and silver gained 46 percent over the previous year's total. Copper and zinc production-entirely as byproducts from other ores-showed an increase, but remained minor. Production of tin was relatively small, but substantially above the total for 1949.

Jan 1, 1953

By Edward Cadwell

El presente texto señala la clasificación de combinación de minerales a través los desperdicios estériles y altos y concentrados bajos.

Jan 1, 1959

By R Hartner

Digital optical microscopy (DOM) and automated SEM-based (ASEM) mineralogy systems (MLA, QEMSCAN) have experienced significant developments within the last decade. However these developments have been independent from each other and the two mineralogical techniques have so far not yet been integrated to combine the strengths and technical benefits of both analytical platforms. This detailed comprehensive mineralogical information is critical support for geometallurgy.Major hardware and software advances in DOM in the last few years have provided important new capabilities with potential applications to automated mineralogy. These technological advances have been largely driven by sectors outside mining (eg medical pathology) and have not yet been widely adopted within the minerals industry. The advent of DOM offers significantly more automated mineralogy capabilities than traditional expert-mineralogist driven optical microscopy. This is based on advances in automated image acquisition, high resolution cameras for digital imaging, imaging of large areas through mosaic options, integration of multiple layers and application of advanced image analysis techniques.Ongoing research involves combining the outputs of DOM and ASEM-based microscopy to create new capabilities for integrated microscopy based on development of advanced cross-platform image fusion and data integration between DOM and ASEM (exploiting the benefits of both analytical platforms). This requires non-linear image registration and transfer of mineralogical identification from ASEM to DOM systems using sophisticated image manipulation and data analysis software.Examples will be given of image fusion and data registration for a range of different ore types. Image fusion techniques are demonstrated using a porphyry copper deposit sample where sulfides and precious metals are classified using the MLA and gangue mineralogy obtained from DOM images. Data integration enables creation of a library containing optical property variability information for minerals identified by the MLA; thus reducing the reliance on skilled mineral identification by supplementing human interpretation

Sep 5, 2011

By J. H. Fowler

Canada's gypsum industry began over two hundred years ago in the Maritime Provinces when farmers attempted to supplement their incomes by selling "land plaster" to traders bound for the United States. Rising from such humble beginnings, gypsum now contributes significantly to the economies of nine of Canada's ten provinces. Thirteen open-pit and three underground mines produced a total of 8.38 million tonnes of crude gypsum and seventeen processing plants manufactured 2.49 million tonnes of finished products in 1985. Recent economic growth in North America has resulted in steady increases in gypsum production, however, competition from foreign producers and by-product gypsum poses a growing threat to Canada's gypsum mining industry.

Jan 1, 1987

By D. G. Puglio

This Bureau of Mines study covers 25 underground mines that were active in the Upper and Lower Freeport and Lower Kittanning coalbeds in 1976. The coal ranges from low to medium volatile in rank; its primary use is for steam generation. Seven mines emit more than 100,000 cfd of methane gas; those mines are the deepest and largest producers. The methane gas content of three core samples of the Lower Kittanning coalbed was estimated by the direct method. A sample from a depth of 320 feet contained 0.5 cu cm of gas per gram, at 620 feet there was 0.8 cu cm of gas per gram, and at 1,060 feet there was 11 cu cm of gas per gram. These results suggest that methane control problems will be encountered in the future as deeper coal is mined.

Jan 1, 1979

By J. D. Miller

The recent non-equilibrium electro-phoretic mobility measurements by laser-Doppler electrophoresis coupled with the stability and prevalence of collector colloids in soluble salt flotation systems suggest that the selective flotation of alkali halides is due to the adsorption of oppositely charged collector colloids by hetero-coagulation. Previously reported flotation results confirm this surface charge/collector colloid adsorption model. However, the nature of the inter-particle forces responsible for hetero-coagulation of such oppositely charged particles at high ionic strengths remains to be determined. In this regard, atomic force microscopy was used for inter-particle force measurements at high ionic strengths. Model systems such as polystyrene/quartz and silica/sapphire were studied to measure the particle interaction forces prevalent at high ionic strengths. Results from this study indicate that while repulsive hydration forces exist between similarly charged hydrophilic particles, attractive forces exist between oppositely charged hydrophilic particles in high ionic strength solutions. The repulsive forces between similarly charged hydrophilic surfaces at high ionic strengths (2-4 M) are described by a double exponential function with decay lengths of 0.17 and 1.4 nm depending upon the surfaces involved. On the other hand, attractive forces were observed between oppositely charged hydrophilic surfaces at high ionic strengths (2-4M) and were described by a single exponential function with decay lengths of up to 9 nm depending upon the surfaces involved.

Jan 1, 1996

By Bruce I. Thomas

The occurrence of tin-bearing gravels along Tozimoran Creek in central Alaska has been known for a number of years. In September 1944 the Bureau of Mines investigated an area approximately 1,000 feet long and 200 feet wide along Tozimoran Creek to deter-mine the cassiterite content of the stream gravels, which are about 4 feet deep and covered by 3 feet of overburden. Nine trenches and two shafts were excavated, from which samples of the underlying gravels were taken. This report contains a discussion of sampling methods and tables giving the results of analyses.

Jan 1, 1948

By Daniel A. Jones

The Surface Mining Control and Reclamation Act of 1977 establishes a nation-wide program requiring the Secretary of the Interior, through the Office of Surface Mining Reclamation and Enforcement, and the States to protect against the adverse effects of coal mining and to reclaim previously mined lands left without adequate reclamation. The Act requires coal mine operators to: restore the land to approximate original contour, return the land to a condition capable of supporting prior potential uses, protect the hydrologic balance, segregate and restore topsoil, control blasting to prevent damage and injury, establish vegetative cover, and control surface effects of underground mining. The Act also establishes: a reclamation fee on coal, a program to assist small operators, a program to give technical and financial assistance to State programs, State Mining and Mineral Research Institutes., a program for designating areas as unsuitable for mining, and a study on surface mining of minerals other than coal.

Jan 1, 1977

By G. A. Gruber

A flotation process has been developed to successfully treat ore from the Santo Domingo phosphate deposit in Baja California Sur. The ore contained less than four percent P205 with quartz, silicates, and carbonates as gangue minerals. Flotation of the low grade feed In sea water required that the conventioinal Crago Process, comprising direct anionic flotation, deolling, and inverse cationic flotation be augmented by an anionic cleaner flotation step, phosphate depression, and a calcite flotation step.

Jan 1, 1986