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By S. H. Lorain

This paper is one of a series on mining methods and costs being published by the U. S. Bureau of Mines. The operations of the Quartz Hill Mining Co., near Dewey, Mont., afford an interesting example of the cost of mining small bodies of direct shipping ore; they also illustrate the effect of the unavoidable periods of unusually high exploration and development costs in this type of mining upon the cost per ton of producing ore. The importance of skilled geological guidance and the necessity of avoiding unnecessary overhead and capital expense at small mines are shown. Operating conditions at Quartz Hill are typical of those in many other mining districts of southwestern Montana. It is believed that the costs presented here may be of value in the preliminary estimation of costs to be expected by conservative operators under similar conditions elsewhere. The information contained in this paper was obtained during a visit to the Quartz Hill mine in August 1936.

Jan 1, 1937

By Charles H. White

METHODS in colorimetry are based on the assumption that the intensity of the color of a definite volume of solution is directly proportional to the quantity of the color-producing substance' present. In the preparation and examination of colored solutions there are three ways in which the depth of color may be varied. These variables are; (1) the quantity of the coloring matter, (2) the quantity of the solvent, or the dilution, and (3) the thickness or depth of that portion of the solution examined. With these three variables as a basis, three general methods in colorimetry have been devised, all of which have been used in the determination of carbon in steel. In the first method, the quantity of the solution is kept the same for both the unknown steel and the standard, and the sections compared are of equal thickness, while the quantity of the standard is varied until the color obtained is of the same intensity as that produced by a definite quantity of the unknown steel. In laboratories where this method is used there is pre¬pared and kept for permanent use a series of solutions with varying amounts of the standard, representing the percentages of carbon from the lowest to the highest demanded in that laboratory. These standard solutions are kept in bottles, or test-tubes of equal diameter, and are arranged in series from the faintest to the most intense color, so that it is a simple matter to find the place of the unknown steel in the series, when the solution is of a definite volume and is contained in a tube of the same diameter as the standard tubes. In the second method, equal quantities of the standard and of the unknown steel are dissolved, the standard is diluted to a definite volume, and the solution of the unknown steel is di-

Sep 1, 1906

By H. W. McCue, Henry Rogatz

Oil.—In the Texas Panhandle, 502 oil wells were drilled during the year 1940, with a total daily initial production of 139,187 bb1.—that is, 137 more oil wells drilled than in the previous year, with an increase in total daily initial production of 8219 bbl. The total daily potential of the field on Dec. 31, 1940, as determined by the Texas Railroad Commission, was 1,375,502 bbl., an increase of 30,825 bbl. over the previous year. On Dec. 31,1940, a daily allowable of 85,050 bbl., which was a decrease of 35 per cent over 1939, was assigned to the field to be produced from 4788 wells. The total amount of oil produced for the year was 26,788,590 bbl., making a cumulative total of 378,960,728 bbl. during the past 19 years. No new oil-producing acreage was discovered. Gas.—During the year, 92 gas wells were drilled, having a combined open flow of 2,402,900.000 CU. ft.; that is, 6 more than the number of wells drilled in 1939, with an increase in the open flow of 204,900,000 cu. ft. per day. The gas production for the year was 670,435,112,000 CU. ft., and the total gas removed from thc ground during

Jan 1, 1941

By Henry Rogatz, H. W. McCue

Oil.—In the Texas Panhandle, 502 oil wells were drilled during the year 1940, with a total daily initial production of 139,187 bb1.—that is, 137 more oil wells drilled than in the previous year, with an increase in total daily initial production of 8219 bbl. The total daily potential of the field on Dec. 31, 1940, as determined by the Texas Railroad Commission, was 1,375,502 bbl., an increase of 30,825 bbl. over the previous year. On Dec. 31,1940, a daily allowable of 85,050 bbl., which was a decrease of 35 per cent over 1939, was assigned to the field to be produced from 4788 wells. The total amount of oil produced for the year was 26,788,590 bbl., making a cumulative total of 378,960,728 bbl. during the past 19 years. No new oil-producing acreage was discovered. Gas.—During the year, 92 gas wells were drilled, having a combined open flow of 2,402,900.000 CU. ft.; that is, 6 more than the number of wells drilled in 1939, with an increase in the open flow of 204,900,000 cu. ft. per day. The gas production for the year was 670,435,112,000 CU. ft., and the total gas removed from thc ground during

Jan 1, 1941

By P. M. Tyroler

Inco operates a hydrometallurgical plant to treat the residue from the pressure carbonylation process. The main constituent in the residue is cop¬per. The residue is leached under pressure in an acid sulphate solution in two stages and the copper is recovered via electrowinning. The electrowinning tankhouse is fully integrated into the overall plant flowsheet as spent elect¬rolyte is required in upstream leaching steps. In recent years, the amount of residue had increased and copper removal capacity became the rate limiting factor for the entire plant. Consequently, a major program was undertaken to upgrade the tankhouse with regards to capacity, efficiency, cathode quality, working environment and structual integrity and appearance. This paper will describe current facilities and operation, and detail progress in our up¬grading efforts.

Jan 1, 1987

By J. P. Smith

Permian salt measures carry extensive lenses of soluble potash salts in north central Germany. Potash deposits of Oligocene age are found in the Upper Rhine Graben of Alsace (France), and in the Catalonian Basin of Spain. These deposits are found in a wide range of structural settings. Reserves are large, and the production of potash salts is an important phase in the economy of each of these countries.

Jan 1, 1950

The content of the book covers: (1) The theory of the Eötvös torsion balance; derivation of the working formulas; description of the instrument; method of observation; relation of the magnitudes observed to the lines of force and the level surfaces of gravity; corrections or normal effects, near and distance terrane; subterranean effects; effects due to certain mathematical bodies. (2) Notes on the practical employment of the Eötvös torsion balance; initial testing of the instrument and of accessories; hints on planning the survey; work at the station site; office computation and plotting of results; the interpretation of the results: (3) A description of the instrument and instructions for its manipulation. This book was the best discussion in English on the theory and use of the Eötvös torsion balance and is surpassed only by a later paper by the same authors that covers much of the same ground. The book is suitable for a textbook for beginners, and advanced students will find it of use. It should be available as a reference book in all geological libraries and in all torsion balance department offices.

Jan 1, 1929

By H. F. Yancey

Traditionally the Pacific Northwest has relied on hydroelectric power, which has been both abundant and cheap. However, comparatively few hydroelectric sites capable of providing low-cost power remain, therefore the need for supplemental thermal generation, perhaps within the next decade, is generally recognized. Based on the present cost and availability of competing fuels, coal seems to be the logical choice for projected thermal power plants. Power companies and public utilities have become interested in establishing reserves of coal for future use. One deposit explored in 1958-59 lies in southern Thurston and northern Lewis Counties, Wash., near Centralia. Drilling, totaling 22,700 feet, proved the existence of 70 million tons of strippable coal--an ample reserve for the projected power plant. The coal, like most others and particularly those of Washington and Oregon, when mined in full seam section by mechanical methods, would require cleaning to make it suitable for use. The amount and nature of the impurities in this coal dictated a thorough investigation of its cleaning characteristics to establish economic factors and to insure proper preparation-plant design. Therefore, arrangements were made through a cooperative agreement to conduct such work at the Seattle Coal Research Laboratory of the Bureau of Mines. This report describes that investigation. The results are of interest primarily in connection with the utilization of this particular deposit, but some of the information developed is applicable to other deposits of low-rank coals in the West, because the impurities in these coals differ greatly in behavior from those generally associated with the higher rank coals of the Appalachian field.

Jan 1, 1961

By H. S. Martin

This paper, describing the concentrating practices at the plants of the Utah Copper Co., is one of a series being prepared by the United States Bureau of Mines in which the data are given in as nearly uniform c manner as possible. The Magna mill is 19 miles west of Salt Lake City on the routes of the Lincoln and Victory highways, and the Arthur plant is 1 mile west of the Magna mill. Both are on the main road west of the town of Magna and east of the town of Garfield.

Jan 1, 1931

By David Scott

THE MOGOLLON mining district, New Mexico, has received little public attention, although for 15 years it has been the leading silver producer of the state; it is situated in a region remote from the principal lines of travel, and its activities have usually been limited to the operations of two or three companies. The value of the total production of the district in the 44 years of its history has been estimated at $15,000,000. For the years 1904 to 1917, inclusive, the output was: gold, $4,370,000; silver, 10,042,000 oz.; copper, 874,862 lb.; total value, approximately. $10,500,000. In 1913 the district contributed 80 per cent. of the total silver production of New Mexico, but in 1917 only 41 per cent., due to serious interruption in the operations of the leading producer. Since 1914 the silver output has diminished one-half, and the present high value of silver is nearly offset by the increase in cost of production. The output of gold has rarely exceeded 35 per cent, of the total for New Mexico. The ratio of silver to gold, by weight, has averaged 46:1 based on the whole output of the district. LOCATION AND TOPOGRAPHY The town of Mogollon is 75 mi. (121 km.) by a poorly located highway from the nearest railroad terminals, at Silver City and Tyrone. All supplies are transported by motor trucks and teams. The area, sometimes called the Cooney Mining District, lies on the western flank of the Mogollon Mountains, which occupy the western part of Socorro County. The elevations drop steeply on the west to the valley of the San Francisco River, adjacent to the Arizona boundary. The topography is very rugged, the whole area being sharply dissected; deep canyons with steep gradients and rugged walls are characteristic of the whole western-slope of the Mogollon Range. The main canyons run east and west, and usually maintain a flow of water during the entire year. As would be expected in a region of such deep dissection, the

Jan 2, 1920

By P. Malíková, I. Osičková, R. Sousedíková, P. Rys, J. Dvořáček, S. Heviánková

Each mining project goes through the same life-cycle, from prospecting and exploration to closure and post-closure periods. This prompts the question whether the closure of a mine constitutes the end of its life-cycle or whether the decommissioned mine can be employed for some other purpose. Best-practice references indicate that there are many viable options. In our opinion, the production of service water is one such option. Laboratory research was carried out on the water from a flooded underground coal mine in Ostrava- Karviná coal district, Czech Republic, concerning the production of service water from pumped minewater. The research proved the practical feasibility of service or process water production. Given the effect of global climate change with regard to water resources, good prospects for this additional resource can be assumed since the water has to be pumped in any case for safety reasons.

Oct 1, 2022

By Jack G. Hazan

The Critical Path Method is the modern scientific answer for solving the planning and scheduling problems inherent in today's complex projects. With this method, nothing is left to chance. All resources are controlled and kept to the minimum. The various phases are properly planned and strategically determined. Optimum conditions are evaluated for the most economical and fastest way to complete a definite project. The method must be fully understood and implemented with positive data and continuous feedback to obtain the best results. This paper covers the various aspects of the Critical Path Method and mentions some of its applications in the mining and metallurgical fields. T 0 progress to a higher state of human welfare necessarily involves sacrifices. The greatest sacrifice is to relinquish social freedom in favour of economic freedom. In the old days, for example, a cobbler was free to work at whatever time of the day he chose; today, he can't. He is now forced to adapt himself to environment and to work at stand-

Jan 1, 1965

By L. M. Pidgeon

"Part I. - PrinciplesIntroductionIf the oxides of the metals are listed in decreasing order of the magnitude of their heats of formation, the list appearing in Table 1 will be formed. It will be apparent at once that this is essentially the well-known electrochemical series (Table li). The metals at the bottom of the list exhibit great stability and are attacked only by the most violent of chemical reagents. Higher on the list, the metals become more reactive until, at the head of the list, the metals lithium and calcium are unstable in moist air.The reactive metals to be considered lie above manganese. In this group will be found familiar and abundant metals such as aluminium and magnesium, the unfamiliar yet abundant metal titanium, the rare and mysterious metal beryllium, and others of greater or less interest.While these metals exhibit properties as unlike as those of uranium and magnesium, they have in common a specialized and difficult extractive metallurgy. They form compounds of great stability, and their reduction is to varying degrees difficult. The position of a metal in Table 1 (and more particu1arly its position in the free energy column) gives a numerical value to this property.Oxides with low free energies of formation may be reduced with great ease; thus silver and mercury may be produced from their oxides by simple heating in air.Lead, iron, and zinc may be separated from their oxides by heating with carbon to moderate temperatures. Magnesium oxide, on the other hand, .requires a high temperature and very special conditions before it will yield magnesium metal."

Jan 1, 1950

Watershed Jll in Jefferson County, Ohio we instrumented in 1977 as one of three watersheds established for the purpose of investigating surface mining and reclamation effects upon local hydrology, sediment discharge, and sediment and water quality. Each watershed was less than 50-acres in size, and was in a different geologic setting within southeastern Ohio. Surface runoff and ground¬water levels were monitored. Samples were taken for sediment determination and chemical analysis prior to mining. Monitoring and sampling continued through the period of watershed disturbance caused by mining and reclamation activities, which began in May 1980 at Watershed Jll. A psuedo-postreclamation period followed the initial cessation of man-machine activity on the watershed. A second reclamation effort occurred in the fall of 1981 and was to be followed by a third in 1982 after observations ceased. A true final postreclamation period was not monitored at this site, because the erosion control practice (terrace diversions) failed after each reclamation. Watershed Jll was a small pasture and wooded watershed with sandstone and shale above the mined coal seam prior to mining. A clay layer under the coal supported a perched saturated zone, termed the top aquifer for convenience. A lower underclay supported a second saturated zone called the middle aquifer. A lower perched aquifer had been dewatered by previous deep mining. After about three years of premine data and about two and one-half years of mining reclamation and psuedo-postreclamation data, the following general observations may be made: 1. The mining-reclamation phase was very short, and the postmining period was characterized by erosion failures and remedial disturbances that kept the watershed condition and size in a state of change. It was impossible to collect sufficient data to confidently characterize the hydrologic-sediment-chemical aspects of the mining period or of a postreclamation period and, most importantly, of the future watershed after its various properties and characteristics have ceased adjusting to its severe disturbance and reconstitution. 2. A seeding of wheat followed by grasses and legumes was not a particularly successful reclamation practice in terms of stabilizing the new soil. Numerous rills and small gullies developed in spite of installed diversions. 3. Storm runoff rates and yields at the watershed outlet increased from the premine, (phase 1) to the mining-reclamation (Phase 2) periods, and remained at or near the Phase 2 level through the postreclamation (Phase 3a) period. 4. The top aquifer changed in physical and chemical character as a result of mining and was becoming reestablished as the project drew to a close; but it is impossible to predict its final configuration or character. 5. Dewatering of the top aquifer resulted in a complete cessation of baseflow because the middle aquifer water table lay below the elevation of the watershed outlet. 6. The top and middle aquifers were merged in one area of the watershed where the upper coal underclay was disturbed. 7. Failure of the diversion terraces and their outlet obscured the effects of the reclamation practice upon sediment concentration and yields. There was little difference in sediment concentrations between Phases 2 and 3a. 8. Drinking water standards were met by surface waters throughout the period of observation except for two samples that exceeded the nitrate-N allowable level of 10 mg/l. 9. In all Phase 3 surface-water samples, iron concentrations were within the limits established by OSM, and manganese concentrations exceeded the regulation level only once. pH fell below the lower regulation level of 6.0 between 10% and 20% of the time. 10. The chemical quality of sediments was generally about the same after reclamation as before mining, with the exception of organic carbon, which decreased.

Jan 1, 1983

By P. Groleau, O. Tavchandjian, D. Marcotte

In open pit mining, each small mining unit (SMU) is selected for mill processing based on an estimate of its true grade. The estimation is usually done using analyses of cuttings from blast holes within that SMU. One common estimator used for selection is the arithmetic average of within-SMU samples. This estimator is conditionally biased. The effect of a conditional bias is to overestimate the profit really recovered from the deposit. For this reason, a conditionally unbiased estimator is preferable. Increasing the number of samples generally improves the accuracy of the estimation (and diminishes the conditional bias, if present, of most estimators). However, there exists a practical limit where an additional sample does not improve the estimation sufficiently to cover the expense of making the analysis. This limit is specific to each deposit and depends on geostatistical parameters, economic factors, and mining parameters. This study examines how the number of samples affects the recovered reserves and the resulting profit. Also, the effects on optimal profit of varying the different factors are examined. Globally, the number of samples required increases with the selectivity of the operation. For a given ore deposit, the greater the number of SMUs selected for processing, the fewer samples are required and vice-versa.

Jan 1, 1998

By I. Barin

The thermodynamics of cyclone smelting of sulphidic copper ores is described using as example the production of copper matte with 75 wt % Cu. Equilibrium calcualtions and material and energy balances show that an increase in process temperature from 1600 K to 1900 K results in the extensive transfer of minor elements such as As, Sb, Bi, Pb, Zn,.... to the gas phase. A pilot plant for carrying out the cyclone smelting process is described. Calculations of material and heat transfer for the reaction of ZnS show that the smelting reactions of sulphides in the cyclone take place very rapidly at high temperatures. The dissociation of the sulphides with subsequent oxidation reactions in the gas phase plays an important part in. the process and is mainly controlled by heat transfer.

Jan 1, 1983

By Zhaohui Xie, Bin Xu, Qian Li, Yongbin Yang, Tao Jiang

A high carbon low-grade gold ore, in which gold mainly occurs in carbonaceous matters, is a typical refractory gold ore whose conventional cyanide leaching extraction is only 12.9 %. In this paper, by the process of flotation-roasting-leaching, gold was effectively enriched and extracted. The flotation results showed that the enrichment ratio of gold was relevant to that of carbon, indicating that gold occurred in close association with carbon. A concentrate containing gold 7.26 g/t and carbon 12.37 % was obtained, with gold recovery 83.10 % and carbon recovery 90.24 %. Subsequently, the roasting of flotation concentrate favorably made the removal rates of carbon and sulfur reach 99.81% and 98.79%, respectively. After roasting, the gold in the roasted product was further enriched to 29.70 g/t and the optimal gold cyanide leaching extraction reached 93.66%.

Jan 1, 2015

By Peng Lv, Shiqian Liu, Bin Xu, Qian Li, Yongbin Yang, Tao Jiang

The treatment process of a low-grade refractory gold ore containing sulfide minerals and carbonaceous matters was studied in this work. The gold extraction of this ore by all-sliming cyanidation was only 11.75%. Hence, a pretreatment was necessary. In this paper, a flotation-preoxidation-cyanide leaching process was developed. The concentrate from the flotation procedure was processed using different preoxidation methods. A concentrate containing 34.08g/t of gold with the gold recovery ratio of 81.20% was obtained by flotation. After roasting, microwave heating or alkaline pressure oxidation, the gold cyanidation ratio reached 82.37%, 81.26% and 71.09% respectively. Roasting was an effective, reliable and mature technique to oxidize sulfide minerals and carbonaceous matters. Roasting and microwave heating both produced dangerous environmental pollutants while alkaline pressure oxidation was eco-friendly.

Jan 1, 2015

By Charles A. Sorrell

This Bureau of Mines publication reviews the structural characteristics of crystalline phases and phase equilibria data for the system NaC1-KC1-AlC13-NaF-KF-AlF3, which encompasses a large number of molten salt fluxes currently used in aluminum recycling. Its purpose is to provide guidelines for research into the relationships between molten salt compositions and their physical properties, notably vapor pressures, densities, surface tensions, and viscosities, knowledge of which is essential to maximizing fluxing efficiencies and metal recovery and minimizing hazardous emissions and disposal problems. In addition, this report describes experimental determinations of sub-solidus compatibility relationships in the system, which is of the quaternary reciprocal type, containing 12 different stable 4-phase assemblages in the solid state. The compatibility diagram serves to define the important compositional planes across which important changes in properties are likely to occur.

Jan 1, 1986

By H Esterhuizen

The Ernest Henry Mine (EHM) in Queensland, Australia is a Sub-level Caving operation that started production below the previously mined open pit at a depth of 535m. Current Production mining has progressed to a depth of 730m, with planned production mining to extend down to at least 1000m below surface. The inclined nature and geometry of the orebody combined with geological structures provides for challenging mining conditions. Over several years, Ernest Henry Mine has introduced measures to improve outcomes based on observations, monitoring and data analysis. As mining progresses deeper, EHM will continue to proactively take steps to ensure future outcomes are anticipated and mining can continue safely and uninterrupted. The focus of this paper is on the changes in seismic- and stress-driven behaviour of the rockmass experienced at EHM, the ground control measures implemented, and the anticipated future conditions and controls required. CITATION:Esterhuizen, H, 2018. The evolution of seismicity and ground control measures at Ernest Henry Mine, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 20–41 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018