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To Install Waste Heat Boiler at White Pine White Pine Copper Co.'s smelter 18 miles southwest of Ontonagon, Mich., will have a six story high boiler utilizing what otherwise would be waste heat from a copper reverberatory furnace. Designed and under construction by the Babcock & Wilcox Co., the boiler will supply steam to a turbo-generator furnishing power for the projected development. The boiler will be in line with and following the reverberatory furnace. Using waste heat from the furnace in place of fuel for steam generation, about 50 pct of heat in the fuel originally supplied to the furnace will be recovered by the waste heat boiler. Exploration conducted over the past 15 years at White Pine, wholly owned subsidiary of Copper Range Co., has disclosed reserves of 309 million tons averaging 21.3 lb of copper per ton. Ore mineral is chiefly chalcocite (Cu2s).

Jan 5, 1953

By I. N. Zavarine

THE observations presented in this paper were recorded during a study of the spheroidizing process. Spheroidization of cementite in steel is either brought about to develop a set of desirable mechanical properties or is an incidental result of mechanical and heat-treating manipulations. Physical properties of steel are materially influenced by the state of the cementite. Conversion of cementite from the lamellar to the spheroidal state is usually accom-panied by a decrease of hardness and of strength and by an increase in ductility. The spheroidized structure is usually considered as an ultimate step in the process of the softening of steel. The unorthodox hardening of a 3.5 per cent Ni steel (SAE No. 2330) after a heat-treatment that previously proved entirely suitable for a complete spheroidization of cementite in carbon steels led to the observa-tions that constitute the subject of the present paper.

Jan 1, 1939

SEC. 1. The membership of the Institute shall comprise seven classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6. Rocky Mountain Members; 7. Junior Foreign Affiliates. All shall be equally entitled to the privileges of membership, excepting that no member of any class whose residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the class of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain Members.

Jan 1, 1946

U.S. Signs Pact With Miami Copper Miami Copper Co., of Arizona has agreed to mine lowgrade copper ores in an extension of its Globe-Miami mining district operations at a guaranteed price of 27.35[] per lb, under a contract signed with defense Materials Procurement Agency. Terms of the contract call for delivery of 230 million lb of refined copper between 1955 and 1962. DMPA said highgrade ore in the de posit will soon be exhausted and it is considered advisable to have Miami continue the operation. The Government has an option to buy 120 million lb of refined copper from present production at market prices. Miami will develop the new ore- body at its own expense-estimated at $3 million. If losses under the new contract reach a specified point, Miami may cancel the agreement. The company plans to use the block caving method in the underground operation.

Jan 4, 1953

SEC. 1. The membership of the Institute shall comprise seven classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6. Rocky Mountain Members; 7. Junior Foreign Affiliates. All shall be equally entitled to the privileges of membership, excepting that no member of any class whose residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the class of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain Members.

Jan 1, 1946

By Richard F. Miller

The investigations of large-grained specimens carried out by Polanyi and Schmid,l Sykes,2 Goucher,3 Yamaguchi,4 Gough, Cox, and Sopwith,5 Carpenter and Elam,6 Aston,7 and others have shown qualitatively that grain boundaries restrain the deformation of adjacent crystals. But whether or not the influence of the grain boundary is confined to the glide planes intersected by the boundary has not been demonstrated in any of these investigations, nor has there been carried out any quantitative analysis of the influence of a boundary on the deformation of a crystal. Indeed, the specimens employed in the previous work contained so many complicating factors that it would have been difficult to observe any variation of the extent of the influence of the grain boundaries in relation to their sizc. The specimens were small, the grain boundaries irregular and at no particular angle to the specimen axis or the

Jan 1, 1934

By Horace Pops

THE martensitic transformation occurring at cryogenic temperatures in the bcc ß-phase Cu-Zn binary alloys has been discussed in a number of publication~.1-3 Addition of a second solute element to the binary Cu-Zn alloys enables the ternary martensitic phase to be stable at temperatures above room temperature, and the variation of the MS temperature with third element content has been determined recently4 for a series of Cu-Zn based alloys in which either the zinc content or the electron concentration was maintained at a constant value. The present paper describes some characteristic growth features of martensite observed in ternary alloys. Alloys were prepared by adding small amounts of Ni, Ag, Au, Cd, Ga, In, Si, Ge, Sn, or Sb to a a -brass Cu-Zn master alloy. Details of the melting and casting technique, homogenization, examination by cold-stage microscopy, and the determination of the

Jan 1, 1968

By T. B. Counselman

WHEN one thinks of Minnesota iron ore, one thinks of big open pits, where high- grade ore is simply scooped up with a power shovel, loaded into cars, and hauled away for shipment to the blast furnace. On the western end of the Mesabi range, however, are large tonnages of iron ore which contain too much silica to be used directly in the blast furnace, and these ores must first be concentrated to a purer form. The Mesabi range is about 100 miles long and a maximum of 3 miles wide. The iron formation, which in its unaltered form is called taconite: consists of a banded iron- bearing chert. Where the high-grade ore bodies occur, these have resulted from folding and cracking with sub- sequent leaching out of the silica, leaving the iron oxide behind. The big open pits and the underground mines are situated in these concentrations.

Jan 1, 1941

By Henry Emmett Gross, David R. Mitchell, H. E. Oehler

THE production of fluorspar is one of the smaller nonmetallic industries in the United States with a capital investment-about $10,000,000. Shipments from United States mines' in 1936 totaled 176,231 short tons valued at $3,111,268, an average price of $17.65 per ton. The United States produces about 40 per cent of the world's fluorspar, of which about 90 per cent comes from the Illinois and Kentucky deposits along the Ohio River.2 Further detailed information on the fluorspar industry in the United States is given by Hatmaker and Davis.28 Fluorspar is marketed according to the following relative quantities and specifications : [ ] The concentration of the coarser sizes presents relatively little difficulty, good recoveries being obtained with jigs and tables. However, sizes smaller than about 10 mesh cannot be successfully treated by ordinary gravity separation methods and so have been accumulating as

Jan 1, 1938

By Laszlo Valentyik

To separate minerals on a small scale according to their specific gravity, heavy liquids are used, but because of high costs and health hazards they cannot be used in large scale plants. In order to substitute heavy liquids, finely ground solids like magnetite and ferrosilicon mixed with water and clay for the required specific gravity are employed. The clay present in the medium acts as a stabilizing agent since the coarse heavy media solids would sink very fast to the bottom of the container if they were mixed only in water. The optimum amount of clay varies for different processes, but it is generally between 3-6% by weight concentration of solids. As the pseudo-plastic nature of polymer solutions has excellent suspending properties, investigations were conducted at the Institute of Mineral Research to ascertain whether polymers could be used commercially as suspending agents for finely ground heavy media.

Jan 1, 1973

By Guy T. McBride

The 1970's have been considered a pivotal decade for the mineral industries. Undergraduate mineral engineering education is relevant to this theme; in particular, there are three interrelated problems: 1) The goals, and therefore the course requirements, of the under- graduate curricula are in question; 2) The unit costs of undergraduate education appear excessive to those who bear the charges; and 3) The present social ambience detrimentally affects the work attitudes and career motivation of both prospective and in-course students. Any discussion of these problems must bottom upon recognized national needs for minerals and a technologically sound minerals industry staffed by competent engineers, particularly at the exploration, development and production levels. Fortunately, these needs have been recognized and to some extent quantified, and they are even now under further intensive study by some of the most competent members of society and the profession.

Jan 3, 1973

Three years ago, when Sun Energy Development Co. (Sunedo) dedicated its Cordero mine in Wyoming, the company noted that its decision to venture into the coal industry was prompted by the need for domestic energy self-sufficiency. Now, as the energy situation assumes crisis proportions and the cry For coal intensifies, Sunedoo has begun a $21 million expansion program that will double the mine's productive capacity by the mid-1980s. When the Cordero come was originally conceived, Sunedoo obtained permission from permitting authorities to produce up to 11 million t/y (12 million stpy) of coal. But seeing opportunities in the coal market, Sunedoo returned to the agencies in 1976 and came away with permission to produce 22 million t/y (24 million stpy). Of that total permitted capacity, Cordero is expected to produce about 3.6 million tons (4 million st) this year.

Jan 9, 1979

By Phil Hulse

The Atlanta mine is located in east-central Nevada, approximately 360 km (225 miles) from Las Vegas. It lies in Lincoln County, 116 km (72 miles) south of Ely and 80 km (50 miles) northeast of Pioche. The property is currently operated by the Standard Slag Co. under a joint venture agreement with Bobcat Properties Inc, of Fort Lauderdale, Fla. Operations began in May 1975, and the mill is currently processing 109 000 to 122 500 t/y (120,000 to 135,000 stpy) of gold- and silver-bearing ore. Open-pit mining takes place in a breccia zone that occurs between Ordovician limestones and dolomites on the footwall and Tertiary rhyolites on the hanging wall. The quartz breccia ore is among the most abrasive in the world-shovel teeth must be replaced every week, 19-mm-thick (3/4-in.) steel chutes last about a month.

Jan 9, 1978

By K. R. Y. Simha, W. L. Fourney, D. C. Holloway

An experimental investigation was performed to evaluate the role of stress waves in the pre-splitting operation. 3D birefringent Plexiglas models and the dynamic photoelastic technique were used to visualize the stress waves generated by the detonation. Simultaneous as well as sequential detonation of the explosive charges were investigated. The development of fractures and stress waves were recorded using a high speed multiple spark gap camera of the Cranz-Shardin type. The experimental data was analyzed and displayed-on a Lagrangian diagram to present an overall picture of the entire dynamic event. It was repeatedly observed in the tests that the time required for the completion of the pre-splitting operation as practiced in the field is of the same order as that for the transit time for the stress waves between the blastholes thereby revealing the highly elasto-dynamic nature of the event.

Jan 1, 1982

By M. C. Fuerstenau, D. W. Fuerstenau

Long-Chained aliphatic amine salts have been used for the separation of sylvite (KC1) from halite (NaC1) by flotation. It is puzzling how these two minerals, which are so similar chemically and crystallographically, can be separated by this method. Gaudin as postulated that the difference in floatability of halite and sylvite with salts of primary amines depends on ionic size: In the case of amine flotation, the cation would attach itself to the chloride. I have a speculation there, which I cannot prove, that the ammonium group, that is the –NH3 group in the amine, floats potassium chloride because the dimensions of this group as it has been measured in other compounds is almost identically the dimensions of the potassium ion, quite different from the sodium ion, and so it fits where potassium had been, in place of it and not attached to it.

Mar 1, 1956

By Garth M. Crosby, F. McIntosh Galbraith, Bronson Stringham

THE Hercules mine is located in the northeastern section of the Coeur d'Alene district, approximately 1 1/2 miles north of the town of Burke, Idaho. Surface indications of the ore deposit were first discovered in 1886, but regular mine production was not started until 1902 and was continuous until April 1925, when the known ore had been extracted. Incomplete records show that from 1912 until operations were suspended the mine produced 2 1/2 million tons of ore containing 9.4 pct lead and 7.7 oz of silver per ton, together with an estimated 2 pct zinc, 0.3 pct copper, and 20 pct iron. This operation was the first in. a series of mining enterprises culminating in October 1947 with the consolidation of Day Mines, Inc. In the same year it was decided to unwater the levels below the collar of the Hercules shaft in the hope of finding some indication of a recurrence of ore. The unwatering operation has been described in a. previous paper.' The initial exploration, following recapture of the workings, showed sufficient promise to warrant a detailed study of the mineralogy with modern techniques. The general geo1ogy of the Coeur d'Alene district, including a detailed description of the rock types encountered, has been comprehensively treated by Ransome and Calkins' in their classic paper, and only local background description, therefore, is felt to be appropriate here. The Hercules deposit transects a portion of the trough of a broad south-trending synclinorium which has been greatly complicated by faulting. More locally, it lies within a block of ground bounded on the east; by the O'Neil Gulch fault, a steep north-south overthrust of considerable magnitude, and on the west by a monzonite stock, the outcrop of which is 1/2 mile or more wide and 5 miles long. The country rock is composed of thin to medium-bedded argillites and argillaceous quartz-ites of the Prichard and Burke formations, the oldest members of the Pre-cambrian Belt Series of sediments in the area, believed to be of Algonkian age. The contact between them is a conformable gradation. The argillite is colored gray to tannish-gray and is fine-grained, compact, and generally massive in structure. Under the microscope the unaltered argillite is seen to be composed principally of anhedral quartz and a few feldspar grains which were at one time presumably partly rounded sand grains, but as a result of recrystallization and cementation by silica, the interstices are now almost obliterated and quartz grains show crenulate boundaries. The sizes of these crystals vary from 0.5 mm down to 0.1 mm in greatest dimension. In all specimens sericite comprises 10 to 20 pct of the rock and is present abundantly between most of the grains as flakes or shreds which vary considerably in size. Sometimes they form a fine felt-like mat or aggregate, and sometimes flakes are seen which appear to be good muscovite. In some specimens, separated rhombic-shaped carbonate grains are abundant, and in some instances these have been changed to sericite. Mining operations to date have explored the Hercules vein to a maximum vertical depth of 3600 ft below its outcrop, and along a maximum strike-length of 3600 ft on certain of the lower mine levels. The main orebody is irregular in outline, extending over a variable strike-length of 400 to 1500 ft; and it is intersected by a strong transverse fault that has been traced from the surface to the bottom level. This has been named the Hercules fault, and apart from the vein itself, it is the most prominent structural feature in the mine. There is good evidence that it existed prior to the introduction of ore solutions and may have influenced ore deposition, but it was also the locus of important post-ore displacement and shows a progressive right-handed horizontal component reaching 200 ft on the deeper levels. Its vertical component is not definitely known but may be considerably greater. The fault strikes 20° N to 50° E and dips westerly at angles of 70" to 45", flattening in dip where it crosses the original orebody from east to west between 1000 and 1600 ft below the surface. At about 3000 ft in depth the Hercules fault is joined by a vertical fault of similar strike, and the major post-ore dis-placement below their junction is taken up along this vertical branch of the structure, now called the Mercury fault. Recent work has been concentrated in this vicinity. Another structural feature of special geologic interest, though of little economic importance, is the occurrence of a porphyritic dike in this area. This lies a short distance above the Hercules fault, essentially parallel to it, and is 5 to 15 ft in thickness. It appears at first glance to cut the mineralization, suggesting push-apart relationship, but small stringers of the vein minerals have been observed to penetrate the dike for a matter of inches at several points. The dike is thought to be related to the monzonite intrusion. A vertical longitudinal projection of the mine is shown in Fig. 1, which illustrates most of the features discussed above. The Hercules vein was deposited along the course of a strong, persistent shear zone that now appears as a braided network of gouge seams running through more or less crushed and shattered country rock. It strikes 70° N to 80° W and dips southerly at an average of 75". Barren parts of the structure vary in width from less than 1 ft to more than 15 ft. The width of mineralized segments may be double that. Although the evidence is not conclusive, pre-mineral, normal movement along the zone may be 1000 or 1500 ft. The horizontal component is unknown. Post-ore movement appears to have been

Jan 1, 1954

By Francois E. Heuze

Today, the favored option for disposal of high-level nuclear wastes is their burial in mined caverns. As an alternative, the concept of deep disposal by rock melting (DRM) also has received some attention. DRM entails the injection of waste, in a cavity or borehole, 2 to 3 kilometers down in the earth crust. Granitic rocks are the prime candidate medium. The high thermal loading initially will melt the rock surrounding the waste. Following resolidification, a rock/waste matrix is formed, which should provide isolation for many years. The complex thermal, mechanical, and hydraulic aspects of DRM can be studied best by means of numerical models. The models must accommo¬date the coupling of the physical processes involved, and the temper¬ature dependency of the granite properties, some of which are subject to abrupt discontinuities, during [a]- ß phase transition and melting. This paper outlines a strategy for such complex modeling.

Jan 1, 1982

By Heath B. Fowler

The surface mining operations of the Simplot Fertilizer Co. are on the Fort Hall Indian Reservation approximately 16 miles east of Fort Hall, Idaho (Fig 1). The Phosphoria formation outcrops in sec. 2, 3, 11, 14, 15, 22 and 27, T 4 S, R 37 E, Boise Meridian. The ownership of these phosphate-bearing lands is divided between individual Indians and the Bannock-Shoshone Tribe, and the royalties are paid to the respective owners on a tonnage basis, as the rock is mined. The geology and mineral resources of the Fort Hall Reservation were studied by the U. S. Geological Survey in 1913 and reported on in 1920. † However, it was not until the winter of 1945 that exploratory work was undertaken by private enterprise. Diamond drilling was begun by the Simplot Fertilizer Co. in April 1946, and stripping operations were started in June. A camp was established near

Jan 1, 1950

By B. W. Veal, B. S. Chandrasekhar

THE Laue method of orienting single crystals requires the use of tables of angles between crystal-lographic planes, and between zone axes. Such tables have been published for cubic crystals, and some rhombohedra12 and hexagonal3 crystals. A table of angles between planes in ß-tin has also been published;4 these angles refer to only low-index planes, and are not particularly helpful in the actual indexing of spots on a Laue photograph. Furthermore, it is often useful to know the angles between zones which share a common low-index plane. We have calculated such tables of angles for ß-tin and indium, both between planes in principal zones, and between zones passing through principal planes. The results are given in Tables I and 11. The standard formulas were used, with c/a = 0.54554 for 0-tin, and 1.07586 for indium.

Jan 1, 1962

By J. R. Hillebrand

From the abstract, "A realistic ore deposition model to serve as a conceptual framework." Further, on page 246, "The first area of study was the Josephine peridotite, now identified as an ophiolite terrane, located in northern California and southwestern Oregon (Fig. 3). Here, it was felt that we could test the models shown in Figs. 1 and 2 and, if successful, expand the model and test it in other chromite districts in the US and around the world." My comments refer only to chromite deposits in Europe and the Middle East. First, I question that may chromite deposits occur in the idealized ophiolite section shown in [Fig. 1]. Second, although some podiform deposits (referring to morphology) have been important (Gulernan, Turkey, for example), the stratiform deposits are of greater importance in tonnage and frequently grade. Examples include Nada, Yugoslavia; Bulqiza, Albania; Xerolivado, Greece; Saranovsk, Russia; and Abdasht, Iran.

Jan 1, 1984