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By A. G. B. Hayes, C. L. Renzoni

"AbstractThis paper provides a rough outline of economic expectations for the near future and then goes on to discuss their effect on the expected demand for metals, using zinc, copper, nickel and aluminum as detailed examples.IntroductionMINING, as you are all painfully aware, is a cyclical business. We believe that it will remain so as long as there are economic cycles.The fortunes of the industry are tied to those sectors of the economy where decisions can be postponed until more favourable times: automobiles, housing, appliances, inventory building and capital spending. Over the past two years, while U.S. GNP fell by 3.8%, automobile production declined by 31 %, from 9.7 million units in 1973 to 6.7 million in 1975. Housing starts plummeted some 43% from 2.1 million units in 1973 to 1.2 million in 1975. Little wonder that U.S. copper consumption fell by 37% and zinc consumption by 38% over the same period.With the rest of the world's economies moving in unison with that of the United States, it is also not surprising that times have been tough for mining.Arthur Burns, chairman of the U.S. Federal Reserve, contends that each recession sows the seeds of its own recovery. The worse the recession, the better the subsequent recovery. If this is true, then the lot of the mining industry should improve significantly over the next two to three years."

Jan 1, 1977

By J. M. Stuve

Calorimetric data for the dissolution of scandium sesquioxide and scandium trichloride in 4.360 molal hydrochloric acid were used to evaluate the standard heat of formation of ScCl3(c). The heat of reaction for Sc(c) + 1.5Cl2(g) = ScCl3(c) at 298.15° K was computed as -225,440 ±340 cal/mole.

Jan 1, 1965

By A. Eslami

When producing high grade mattes in smelter plants, copper losses in the slag are inevitable. Hence, the recovery of copper from slag has been the focus of many research projects, copper flotation being a widely used process. In the Khatoonabad converter, 200 t/d of slag are presently produced with a grade of 2.3% Cu. Assuming a 85% recovery by flotation, about 3.9 t/d copper could be produced, which is of prime importance economically. In the present work, a sample of this slag was crushed and ground in the laboratory to liberate the copper-bearing minerals. Following mineralogical studies, optimum laboratory flotation parameters were obtained, resulting in 90.27 % recovery and 9.42% of copper grade for the rougher stage. At pilot scale, a pulp of 28% solids was floated at ph 10.5 using 40 git of Z6, 25 git of R407 and 20 git of MIBC and A65. A recovery of 83.52% was obtained for a concentrate grade of 28.36% Cu. In the rougher cells, the feed consisted of particles 94% finer than 74 microns whereas in the cleaning stage, particles were 95% finer than 44 microns. Based on the obtained results, the Sarcheshmeh Khatoonabad converter slag is presently being fed to the Chargonbad flotation plant, where a concentrate of 32% copper at 86% recovery is being produced.

Jan 1, 2007

By N Akizawa, A Tamura, S Arai

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Reaction products between high-temperature hydrothermal solution/uppermost mantle peridotite or lowermost crustal gabbro have been reported along Wadi Fizh of the northern Oman ophiolite; they are named as ‘mantle diopsidite’ and ‘crustal diopsidite’ respectively (Figure 1).The mantle diopsidite contains Cr-rich minerals like chromite, Cr-rich diopside (<2.5 wt per cent Cr2O3) and Cr-bearing grossular (<7.0 wt per cent Cr2O3). The chromites are varied in shape in the mantle diopsidite, euhedral to anhedral chromite grains contain globular inclusions of grossular and chlorite, and film-like chromite veinlets branch off from partially dissolved coarse chromite grains. In the crustal diopsidite, fine chromite grains are included in oscillatory-zoned skeletal uvarovite, especially in its high-Cr zones. The uvarovites are rich in rare earth elements (REEs). Direct laser ablation – inductively coupled plasma – mass spectrometer (LA-ICP-MS) analysis of the primary fluid inclusions detected Na, but not K.Our detailed studies of Wadi Fizh diopsidites clarify that the high-temperature hydrothermal solution dissolves chromite grains at the uppermost mantle section and precipitates hydrothermal chromite at the lowermost crust section. In addition, REEs were mobilised in the hydrothermal solution together with Cr. The hydrothermal solution involved in the diopsidite formation is assumed to have been rich in NaCl, and could mobilise appreciable amounts of Cr and REE.CITATION:Akizawa, N, Arai, S and Tamura, A, 2015. Chromium and rare earth elements mobility by sodium-bearing high-temperature hydrothermal solution – an example from mantle diopsidite and crustal diopsidite, in Proceedings PACRIM 2015 Congress, pp 291–296 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

President Robert M. von Storch, General Superintendent, Coal Mines and Quarries, Columbia-Geneva Steel Division, United States Steel Corporation, Dragerton, Utah, called the meeting to order at 9:30 a.m. in the absence of John Peperakis, Past President, who was usable to attend because of a mine fire. He welcomed the members with a paper entitled "With Serene Confidence." He also showed a short movie, "The Waiting Harvest," with his speech. Following the president's speech, the first business meeting of the Institute was held. Secretary-Treasurer Fred Whiteside presented the Treasurer's Report. Motion made by Mr. Whiteside, second by Stan Shubart that this report be accepted. Motion carried. Because the minutes of the last meeting were published in the Institute's booklet, the reading of the minutes was dispensed with, and the President announced the members of the various committees: General Chairman ? Charles M. Schloss

Jan 1, 1958

By S. A. Willis

For over 150 years gypsum from Nova Scotia has been shipped via water to the United States east coast. The history of the movement has been one of continual improvements in quarrying, loading, and shipping. At the start, man-size rock quarried by hand auger and black powder was loaded into horse-drawn carts, hauled to the waterfront, and dumped into 100-ton sailing schooners. Last year the Canadian Gypsum Company completed the latest and most modern of these successive installations for the movement of this Nova Scotia product. The new system loads crushed gypsum into 11,600-ton vessels at Hantsport in two hours' time at high tide. At the head of the bay of Fundy are located vast deposits of gypsum. The tidal rise and fall of 45 feet twice a day, with its attendant swift currents, has always presented major navigation and shipping problems. When the tide is low, the Hantsport ship-loading pier is high and dry, with no water within 400 feet. Three hours later a large river has flooded in (running up hill) and large steamers can dock at the wharf. Before high water, the ship has been loaded and -there is a depth of 30 feet or more of water around the wharf. At high water, the ship sails away on the ebbing tide as the river runs in the other direction. Tides are caused by the gravitational attraction of the moon and sun on the ocean. When both celestial bodies are pulling together the 'spring tide' results, which means a 50-foot variation from high to low. This occurs at new and full moon. A week later, when the sun and moon work in opposition, the difference is only 32 feet between high and low water. The bay of Fundy, having a funnel shape (150 miles wide at mouth from Yarmouth to Portland, while the upper estuary at Hantsport is only one mile wide), builds up a tidal influence from 10 feet at the mouth to an average of 45 feet at Hantsport.

Jan 1, 1948

By R. G. Davies

Isothermal annealing of quenched Fe3Al reveals that the superlattice forms by the nucleation and growth of ordered domains. The activation energy for isothermal ordering and initial domain growth is -29 keal per mole, which is thought to he the activation energy for vacancy migration. Domain growth, in the absence of excess vacancies, has an activation energy of -100 keal per mole. A maximum in the hardness is observed when the structure consists Of ordered domains, -35-4 in size, growing into a short-range ordered matrix and, also as a function of degree of order, S, with an infinite domain size at S = 0.4 to 0.5. It is proposed that both maxima are due to a transition from deformation by unit dislocations to deformation by superdislocntions. FE-AL alloys containing more than -23 at. pet Al, when quenched from above the critical temperature for the Fe3A1 type of order, always contain the maximum possible amount of FeAl (B2) type of order' (see Fig. 1). Thus when the Fe3A1 superlattice forms, in a 25 at, pet A1 alloy, it does so from an imperfect FeAl structure. The formation of the Fe3Al superlattice has been the subject of several recent X-ray,1, 2 electrical-resistivity,3"6 and dilatometric3 investigations. McQueen and Kuczynski3 concluded that the isotherma1 ordering of Fe3Al, after quenching from 800°C (T,, the critical temperature for order, is 55O°C), takes place by the nucleation and growth of ordered domains. However, Feder and Cahn4 found that the isothermal ordering was complex but more like a homogeneous nucleation process than a nucleation and growth process. Lawley and Cahn2 reported that the degree of order is a continuous function of temperature which is a characteristic of a homogeneous nucleation process. Thus, the evidence is conflicting as to the nature of the Fe3Al ordering reaction. Lipson7 was the first to suggest that ordered domains should exist in the Fe3A1 structure since, as

Jan 1, 1964

By Paul E. Richardson, Edwin E. Maust

Cyclic voltammetry and surface potential (photovoltage) measurements have been carried out on galena electrodes in sodium tetraborate solutions with added HC1 and NaOH to adjust the pH over the range 2 to 13. The first technique shows that the surface species formed on moderate anodic polarization and reduced on subsequent cathodic polarization are the same over the entire pH range. At anodic potentials, a soluble metal species and excess sulfur are formed; at cathodic potentials, sulfur is reduced to a soluble species. More importantly, excess surface sulfur is formed spontaneously under zero current conditions in alkaline solutions. This has been shown to occur on both polished surfaces and on virgin surfaces produced by in situ cleavage under the electrolyte. The photovoltage gives some insight into the charge and potential distribution at the galena surface. This is found to depend on past electrochemical history and the n- or p-type semiconducting character of the electrode and is interpreted in terms of changes in the surface stoichiometry that occur during reduction or oxidation. The effect of surface stoichiometry on subsequent xanthate interactions is discussed.

Jan 1, 1976

By T. Kalliomäki, A. T. Aji, M. Lundström, J. Aromaa

The settling properties of anode slime in copper electrorefining have crucial effect on copper cathode quality. Anode slime settling is affected by electrolyte composition and temperature, electrolyte circulation, and the sizes and density of the slime particles and agglomerates. Typically, the industrial copper electrolytes contain 40–60 g/dm3 Cu2+, 130–220 g/dm3 H2SO4, 0.04–25 g/dm3 Ni2+, 0.005–30 g/dm3 As, and have operating temperature of 55–70°C. In optimal electrorefining process, the settling rate of anode slime is sufficiently high to avoid the risk of getting the slime entrapped in copper cathodes. In this research the settling properties of copper electrorefining bottom slimes, mainly consisting of Cu, Ni, Ag, Se, Pb, As, Bi, Sb and Ba compounds, were studied by settling rate tests. The tests were conducted in water and synthetic electrolytes with known viscosities and densities. In addition, the effect of agglomeration was taken into account – it was observed that breaking the agglomerates which existed in the as-received slimes decreased the particle sizes on average 56–73%, which decreased the settling rate. The results of this study provide detailed information of anode slime settling and thus clarify the conditions causing cathode contamination risks in copper electrorefining. INTRODUCTION Settling rates of Cu-ER anode slimes affect the purity of cathode copper and faster settling rate decreases the contamination risk (Davenport et al., 2002; Shi & Ye, 2013). The settling rates are affected by the properties of anode slime particles (Wills & Napier-Munn, 2011; Aaltonen, 2014; Kiviluoma, Aaltonen, Aromaa, Lundström & Forsén, 2016) as well as viscosity and density of the electrolyte (Davenport, King, Schlesinger, Biswas, & Robinson, 2002; Shi & Ye, 2013). Thus, it is crucial to find out how the viscosity and density affect the settling rates. Small spherical particles with diameter below approximately 50 µm obey Stokes’ law (Equation 1) (Wills & Napier-Munn, 2011). v = gd 2 (ρS – ρF) (18η) -1 (1) where v is terminal velocity (m/s), g acceleration due to gravity (m/s2), d diameter of particle (m), ρS density of particle (kg/m3), ρF density of fluid (kg/m3), and η dynamic viscosity (Pa∙s). The approximate effects of kinematic viscosity (ν = η / ρS), density (ρS) and particle sizes on settling rates defined for small anode slime particles based on Stokes’ law are presented in Figure 1. However, Stokes’ law does not take into account other than spherical shapes, and it is only applicable for small particles. Consequently, the real settling rates of the particles are lower than these (Wills & Napier-Munn, 2011). Moreover, some of the anode slime particles are larger than 50 µm (Aaltonen, 2014).

Jan 1, 2019

By Brinton C. Brown

This paper describes the methods and equipment developed at the Bureau's Experimental Oil-Shale mine near Rifle, Colo., for placing men in position to scale loose rock from the walls, pillars, and roofs of high stopes or rooms. The equipment developed at Rifle has application not only in oil-shale mining but in most of the country's underground limestone mines and in the exploitation of other mineral deposits mined in high stopes by room-and-pillar methods. Equipment in use at Rifle includes: 1. A boom-type scaling rig with a self-leveling platform constructed on a small "cat"-mounted crane. Men working from the platform on this machine can efficiently scale mine walls and roofs 27 feet above the floor. 2. A conventional fork-lift truck modified to provide a remotely controlled working platform from which men can scale to heights 27 feet above the mine floor. The platform on this unit is larger than on the boom-type rig and allows the men to inspect larger areas of the mine wall from a single setting of the machine. 3. A third rig, consisting essentially of a platform mounted on a tele-scoping tower, designed and built to elevate men 65 feet above the mine floor. Versatility of this machine permits men to work from the platform at heights of 5 to 65 feet. In the operating position, the unit requires a minimum clearance of 25 feet. In the nonoperating position the tower of the machine folds to an over-all height of 15 feet 10 inches to permit travel through haulageways. 4. An industrial gun, lightweight scaling bars, and mechanical scalers, which have been tried for removing loose rock from the mine walls with varying degrees of success.

Jan 1, 1950

By R. A. Guidotti

The Federal Bureau of Mines studied the thermal decomposition of the nitrides of the Group V A metals (CbN, Ta3N5, and VN) with the goal of preparing high-purity metals. Solid-state purification and arc and electron-beam melting were examined. Electron-beam melting proved to be the most efficient means of nitrogen and oxygen removal. Columbium and tantalum of 99.9-pct purity were prepared by this technique; in the case of vanadium, however, nitrogen could not be reduced below the solid-solution level.

Jan 1, 1976

By Wang Ding-heng, Wang Zhi-yuan, Nolan B. Aughenbaugh

The People's Republic of China has abundant coal resources with proven reserves amounting to 582 Gt (641 billion st). Recognizing coal as a major energy source on which to build the country's industrial and economic base, there has been a rapid increase in production since the founding of the People's Republic. In 1949, only 29.4 Mt (32.4 million st) of coal was mined. Production has increased to 576.5 Mt (635.5 million st), exclusive of Taiwan, at present, making China the third largest coal producing country in the world. Plans call for a 4-5% increase in annual production for the next 20 years. Coal constitutes 70% of the primary energy consumption in China. The remaining 30% is divided between petroleum and natural gas with 26% and hydropower with 4%. Coal use and consumption is divided as follows. General industrial use comprised 48.9%, power generation uses 20.1%, and coking accounts for 10.5% (6.3% for metallurgy and 4.2% for chemical industry). Domestic use such as home heating and cooking makes up 17.8% and coal-fired steam engines for railways uses 4.7%. Coal Districts Coal underlies about 1/18 of China's land area. It occurs in 30 provinces, autonomous regions, and municipalities. In addition, the western interior region, which has not been explored, may contain sizable reserves. Based on geology, geography, and administration, the coal fields can be grouped into five districts as shown in Fig. 1. The north China district, the heart of the industrial base for the country, has the most extensive and largest deposits of the five districts. This amounts to almost 40% of the country's total reserves. The largest coal basin with proven reserves of 181.4 Gt (200 billion st) and the most exploitable seams is located some 300 km (186 miles) southwest of Beijing (Peking) in Shanxi Province. Centered around Taiyuan, the compound field extends from Datong in the north to Xian in the south. Its western extension is not known fully. The Northwest and Northeast districts contain the second and third largest deposits. The biggest coal field in South China is located in the Sichuan and Guizhou Provinces near Chongqing. At present, it is not known if sizable coal measures exist in the Tibetan district. Coal Types China's coal varies widely both in age and rank. Geologically, coal measures were deposited from the lower Carboniferous (Pennsylvanian of the US) and Permian of late Paleozoic, mainly during the Jurassic of the Mesozoic and peri¬odically throughout the Cenozoic. Collectively, coal from the lower Carboniferous, Permian, and Ju-

Jan 3, 1983

Recognizing the fact that the problems of the committee named by the Board to prepare the "official ticket" for officers ' and Directors of the Institute are various and difficult; and desiring to assist this committee by setting forth some of the principles that should guide the committee and some of the qualifications that should be required of candidates, the following instructions are formulated and the Secretary is directed to publish them in MINING AND METALLURGY concurrently with the publication of the names of each newly appointed Nominating Committee and to send a copy to each member of the Committee.

Jan 1, 1944

By R. J. Burgess

During World War II the shortage of ore revived interest in eastern iron deposits, among which -!2..c "Ile Massachusetts and Connecticut limonites. The Cheever mine, in the Richmond-Salisbury area of Massachusetts, was formerly a large producer of limonite ere. The Bureau of Mines investigated the lateral and downward extensions of the Cheever ore body, which was mined from about 1850 to 1892, by ap open cut 1,000 feet long and also by underground workings. even holes aggregating 1,723 feet, were drilled by the Bureau during the winter of 1943-44. They comprised three diamond-core drill holes, two churn-drill holes, and two rotary-drill holes. A geophysical survey of the Cheever mine area and adjoining ground was made in conjunction with the drilling program. Although this survey did not locate the limonite ore beds, the data were of considerable assistance in locating the limestone contact which forms the footwall of the ore beds. Drilling disclosed two beds of limonite with a heavy overburden of glacial till.

Jan 1, 1949

The primary use of coal in the US is for electric generation. The problems associated with the use of this vast amount of coal is the central theme of these sessions. The problems discussed include: production capacity, mining problems, coal cleaning, transportation, combustion, and various environmental problems, such as health effects of coal combustion, water and air pollution, and solid waste disposal.

Jan 1, 1979

By JOHN MARKLE

JOHN MARBLE, mining engineer, coal operator, philanthropist, member of the Institute since 1879, vice-president in 1903-04, has been paid the well deserved tribute of Honorary Membership. The presentation of the diploma was made at a luncheon in New York on Feb. 13, the citation reading: "In recognition of his work as an engineer and administrator of mines and his services to mining engineering education." Within the last month Lafayette University dedicated the new John Markle Mining Engineering Building, the gift of the eminent alumnus for whom it is named. In addition, Mr. Markle has contributed a maintenance fund for the carrying out of far-reaching plans for improving the mining courses to be given at the Institution. One of his theories is that quality rather than quantity of engineering graduates is the need of the profession. John Markle was born in Hazleton, Pa., in 1858. He received his degree of M. E. at Lafayette in 1880, and married Mary Estelle Robinson in New York City in 1884. Since 1880 he has been associated continuously with the firm of G. B. Markle & Co., and its successor companies. He has also been an official of numerous other important companies, although he is now retired from active business life.

Jan 1, 1930

By T. McCallum, C. Cooper, C. Lewis

"Following a successful solvent extraction (SX) pilot plant demonstration in 2016, CYANEX® 600 has been used commercially to recover molybdenum from concentrate leach liquor since March 2017. Consistent with the piloting results, the commercial plant has achieved expected molybdenum recovery, a significant reduction in base consumption, and a step-change improvement in physical performance. This paper highlights the optimization activities and plant performance from startup through normal operation. INTRODUCTION Historically, tertiary amines have been the most commonly used extractant for molybdenum and rhenium recovery. Tertiary amines utilize a protonation of the ligand combined with an anion exchange mechanism as proposed in equations (1-2). R3N + H+ ???R3NH + (1) 4R3NH+ + Mo8O264- ???(R3NH+)4Mo8O264- (2) In addition to the transfer of Mo and Re, the amine transfers acid and other anions to the strip liquor. The undesirable transfer of other species increases base consumption during stripping, impacting operating costs. Additionally, lower solubility of molybdenum-amine complexes create operational challenges, resulting in diminished physical performance. The presence of colloidal Si in concentrate leach liquors and the formation of Pickering Emulsions adds to the physical plant performance challenges with the amine extractant. CYANEX® 600, a phosphinic acid-based extractant, uses a cation exchange mechanism proposed by equation (3). 2(H2R2) + MoO22+ ??(HR2)2MoO2 + 2H+ (3) The cationic exchange mechanism eliminates chemical transfer of acid and other anionic impurities and avoids some of the physical challenges of the amine extractant (emulsion and 3rd phase formation). In addition, the reagent offers high selectivity for Mo over Re, which may be desirable in certain moly pressure oxidation (POX) flowsheets. Alkali base (ammonium hydroxide, sodium hydroxide, sodium carbonate, etc.) is used for molybdenum stripping. Therefore, reduction or elimination of chemical acid transfer from extract can significantly reduce base consumption in strip. Extensive laboratory and pilot plant testing was completed to evaluate the use of CYANEX® 600 for molybdenum recovery at Freeport-McMoRan’s Bagdad operation. The test work and pilot demonstration confirmed a reduction in base consumption along with improved selectivity. In addition, the evaluation highlighted a step-change improvement in physical performance over the incumbent amine extractant. The decision was made to convert the commercial operation to CYANEX® 600 in March 2017."

Jan 1, 2018

Elected Died 1882 *ABBOTT, ARTHUR V 1906 1903 * ADAMS, CHARLES C. 1905 1884 *ADDY, MATTHEW 1896 1894 *ALLFN R B 1896 1874 *AMIOT, H 1892 1886 *AMSLER, CARL 1894 1895 *ÅNGSTROM, CARL 1901 1895 *ARMSTRONG, JOHN F 1898 1882 *ARNOLDS, HUGO 1886 1875 *ASHBURNER, CHARLES A 1889 1872 *ASIIBURNER, WILLIAM 1887 1883 *ATKINS, C M , JR 1885 1897 *AYERS, WILLIAM 1898 1885 *BABCOCK, GEO H 1893 1884 *BAILEY, EDWARD 1889 1880 *BAILEY, JACKSON 1887 1900 *BALLOU, FRANKLIN 1903 1886 *BARNES, F W 1892

Jan 1, 1910

By Pat McCarran

WHEN this Government was founded, the framers of the Constitution wrote into that instrument a provision that Congress should "coin money and fix the value thereof;" and the Constitution prohibits making anything but "gold and silver" lawful money. So silver is written into our basic law. Shortly after President Washington took office in 1789 the Congress passed the first Mint Act, setting up the U. S. Mint. In that Act, signed by President Washington on April 2, 1792, the weight of the American dollar was fixed, and it was provided how much silver should be contained in a silver dollar and how much gold should be contained in a gold dollar. It was decided that 371 1/4 grains of pure silver was to be the standard dollar of America. That standard with respect to the pure silver content of the dollar has never changed.

Jan 1, 1947

By Zhiyuan Ma, Yong Liu, Xianjin Lyu, Jianfang Lyu, Jikui Zhou

A stable and continuous leaching process for niobium and tantalum extraction from ferrocolumbium tantalum (FT) was developed. The effects of initial concentration of HF and H2SO4, grinding fineness, leaching time, and temperature on the leaching rate of Ta, Nb, Fe, and Si were studied. Experimental results show that the leaching rates of Ta, Nb, Fe, and Si were enhanced by the increase of acid concentrate, fineness, leaching time, and leaching temperature. The optimum process conditions are HF initial concentration of 5 mol/L, H2SO4 initial concentration of 2.5 mol/L, − 74 μm percentage of 65%, leaching time of 20 min, and leaching temperature of 25 °C. Continuous leaching of FT was carried out by feeding ore and acid every 20 min. By leaching with HF − H2SO4 for 4 h, then adding appropriate amount of HNO3 into the solution and keeping for another 1 h, a high Nb extraction rate of 99.8% was achieved. The established method provides a promising technique for the high-efficiency separation of niobium and tantalum from FT.

Jun 5, 2022