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By D. Hanson

Fox most of their practical applications metals are required to with-stand stresses of appreciable magnitude: indeed, it is because they possess the quality of resisting stress without becoming permanently deformed that they find such extensive use in the service of man. Metals and alloys must, in service, usually behave as elastic substances-or nearly so. It is not difficult to satisfy this condition at ordinary temperatures. Iron and its alloys, especially the steels, are at normal temperatures excellent elastic bodies, capable of satisfying most of the mechanical requirements of the engineer: where electrical, chemical or other properties are impor-tant, which cannot be met by steels, it is usually possible to find a non-ferrous alloy such as nickel, copper or aluminum, which will prove satisfactory. When the metals or alloys are not inherently sufficiently elastic, cold-working or heat-treatment may develop elastic properties to a sufficient extent for practical needs. By means of relatively simple, rapid tests we can measure such properties as elastic modulus, limit of proportionality and proof stress, upon which design can be based with confidence. The case of the soft metals, such as lead and tin, is well known to be exceptional. They possess no definite limit of elasticity, and the value of proof stress or tensile strength depends to a great extent on the speed with which the test is carried out. Design here must be based on other considerations than a well-established theory of the proportionality of stress and strain. It is now generally recognized that steels and non-ferrous alloys possess at temperatures not greatly exceeding that of the atmosphere, characteristics quite different from those existing at ordinary temperatures, and that they assume qualities similar to those of the soft metals. Not only have they no limit of elasticity, but the proof stress and the ultimate stress depend on the time of application of the load. Flow under load may persist for long periods of time, possibly indefinitely, and the determination of a true maximum stress becomes a matter of great difficulty.

Jan 1, 1939

"7.1. Glossary of the Platinum-Group Minerals7.1.1. IntroductionA glossary of the platinum-group minerals (POM) serves as a useful introduction to a chapter on their mineralogy. Earlier glossaries (Cabri, 1972, 1976) were prepared for different purposes and composed in a different manner. As for most mineralogical textbooks, from Dana's System of Mineralogy, 3rd Edition (1850) , to Fleischer's Glossary of Mineral Species (1980), this glossary is primarily a chemical classification, arranged here in two tables. Table 7.1 groups the mineralforming compounds of the six platinum-group elements (POE) according to their essential anion(s) or according to the nonPOE element in intermetallic compounds. Table 7.2 is a similar listing for the native metals and alloys of the POE. Both tables include unidentified POM considered to be bona fide new minerals requiring additional study for complete characterization and recognition (see Chapter 9*). Some information on the chemistry of the POM is given in the sections on X-ray data (7 .2) and ore microscopy (7 .3). Because the overwhelming majority of POM have been characterized by the electron microprobe, a more detailed account of representative analyses is given in Chapter 8**. The total POM listed in Tables 7.1 and 7.2 is about 100, after deleting some which would not qualify as discrete species if found today, but which are still recognized on historical grounds; e.g. iridosmine, osmiridium, platiniridium. Tables 7.1 and 7.2 also include 28 unnamed POM; included because they are considered to be probably new species (Cabri 1981 b). The referral scheme for unnamed minerals is the same as in Chapter 9. There are considerably more palladium minerals known than other POM; the proportion of total species (listed in Tables 7.1 and 7 .2) for the POE is: Pd 48%, Pt 21 o/o , Ru and Ir 9% each, Rh 8% and Os 5%. These proportions are in marked contrast to the estimated cosmic abundance, as compiled for average type C1 chondrite by Naldrett and Duke (1980): Pt 29%, Ru 20%, Pd, Ir and Os 15% each, and Rh 6%."

Jan 1, 1979

This paper discusses recent ore reserve methodology at the Woodlawn base metal Mine in New South Wales. The ownership of the Mine changed hands in 1987 and a number of revisions to ore reserve practice were instigated by the new operators. While the overall modeling and calculation procedure remained essentially unaltered, the modifications and revised assumptions significantly increased the ore reserve. While general ore reserve procedures are discussed in this paper, it is the impact of these changed assumptions on the reserves which is our main focus.

Jan 1, 1990

By Thomas J. O’Neil

From the time of its emergence as an independent state until the late 1950's, the Republic of Ireland suffered from chronic unemployment, the lowest living standard in Northern Europe, and-most serious of all-an aggravated emigration problem which drained off most of its talented young people. In 1958, however, there was a drastic legislative reaction to these problems, and this in turn ignited the current mining boom in Ireland. Paving the Way to Prosperity In order to reverse the tide of emigration, the Irish government now realized, challenging domestic employment opportunities had to be increased and living standards had to be raised. It was also apparent that future industrial and economic growth in Ireland had to be based on producing goods for export. The home market could not sustain large-scale expansion, and consequently Ireland's chronic balance-of-payments deficit could best be minimized by producing export goods. These considerations, together with the limited amount of accumulated wealth in Ireland, combined to set the objectives of the country's First Program for Economic Expansion in 1958. The general objectives of this program were (1) to stimulate all segments of the economy, (2) to develop foreign trade and (3) to attract foreign capital.

Jan 1, 1970

By John Mathews

SOMEONE has divided mankind into two groups: (1) those who have the willingness and imagination to weigh the future gain over against a present indulgence, and (2) those who cannot do so. The former have self-control, patience, foresight and a capacity for sustained effort. Those having these homely virtues become the, possessors of capital and hence employers of others. Those lacking these qualities and owning no capital must seek it from those of the first class, and therefore are employed by others. The human qualities, which divide men into two classes-employers and employed-are, however, capable of change by education, training, environment and by all agencies which tend to develop character. These words of the economist have stuck in my mind for many years and the more I see of men in my business contacts the more firmly I am convinced of their truth. The earth in some respects resembles its inhabitants. When we stroll over the fields and hills we are impressed by the unorganized masses of sand and rock which make up the ground beneath our feet. When by chance we come upon a bit of mineral matter in crystalline form we are impressed by its beauty and symmetry and probably have it polished and call it a gem. Gems constitute a minute portion of the earth's crust, and those intellectual gems, worthy of polish, who brilliantly reflect the incident rays of education and experience that have fallen upon them are few among the masses of mankind.

Jan 1, 1931

SUMPEARY OF CURRENT PRACTICES History The outcrop and surrounding area of Comincots Sullivan Mine was originally mined by small open cuts on surface and small open stopes underground to which shafts and adits were driven for access. When it was established that a commercial grade of ore was available, an adit was driven on the 4600 level (feet above sea level), and OM was extracted by larger scale open stoping leaving supporting pillars where necessary. After the depth of the ore body was proven to the 3900 level and an adit driven at this level, many miles of drifts, crosscuts, raises and sublevels were driven for the extraction of the ore above this level. Larger open stopea were extended from this development. The mining method was, and to a very limited degree still is, a benching method. Due to the strong hanging wall in this area of the mine, stopes with a width of 100 feet or more were opened. In 1931, because the orebody was proven to extend below the 3900 level, a winze was sunk from the 3900 level to the 3350 level. From this winze three intermediate levels were opened. Following a plan of development well in advance of production requirements, further sinking was done by winzes and eventually a large shaft was raised to surface. Prior to 1958 the 2850 level was bottom which since that time has been extended to the 2500 level. Open stopes were developed and mined as this area was opened up.

Jan 1, 1970

By Horace Winchell

IT IS OFTEN interesting to look backward and review the world's progress in any line of human endeavor. Our pride is flattered by our achieve-ments and our imagination stimulated by the compari-son between our present productivity and prosperity and those of the relatively unenlightened days of our recent ancestors. We love to reflect on the progress of the last quarter of a century in the art of metallurgy, in. the production and consumption of the various metals and minerals which constitute the basis of our industrial and commercial supremacy. We dwell complacently on the figures which prove that we are the world's leader in nearly all departments of mining and that our production of necessary minerals over-shadows that of other countries. We recall the days when it was considered the proper thing, if not indeed indispensable, to go abroad for the rounding out of a mining engineer's education. We had no mining schools equal to those of Germany. Our schools of technology were elementary and their equipment limited. RISE OF AMERICAN MINING SCHOOLS Now we point with true American pride to institutions which, are unsurpassed in all the world in their standard of efficiency. We know full well that the American engineer is in demand in many foreign parts and when we read recent scientific treatises published abroad we are amazed to find them unfamiliar with many of the more advanced ideas which have here already come to be an everyday part of our professional knowledge and equipment. Blessed with a country of unrivalled natural resources, dwelling in a latitude whose climate is most conducive to enterprise, peopled with races of inventive and organizing genius with equality of individual opportunity, our industries have grown and expanded until our output has reached staggering proportions and the draft upon our mineral reserves is appalling. Coupled with this development has arisen a demand for engineers which has brought into our schools of technical science larger and larger numbers of young men whose imagination has been stimulated by the success of their predecessors who happened to be contemporary elements in the recent industrial expansion and prosperity.

Jan 1, 1923

By M. N. Dunlap

Tries article summarizes the successful incorporation of a flash-flooding stream into the tailing-disposal system at the St. Joseph Lead Company's Federal Division mill, in St. Francois County, Missouri. The mill was built in 1906, by the Federal Lead Co., as its No. 3 mill for the concentration of southeastern Missouri lead ores, and damming Davis Creek was first considered in 1908. Plans were made also in 1925 and in 1937. Dam layouts varied from a reinforced concrete structure to a barrier built of tailings alone. All were abandoned because of liability that would be incurred by flashflood rupturing of an incompleted dam. By 1942 mill capacity had reached 12,000 tons daily and increasing tailing-disposal costs again focused attention on the Davis Creek basin. This time the problem of riskless dam building was solved. Moreover, most of the items that appeared in the answer were materials that normally required wasting and the major portion of labor involved performed functions that it would normally have done, without constructive benefit, elsewhere. The new layout also made possible advantageous changes in mill-water supply pumping; static head being reduced from 514 ft to 95 ft, friction head from 4900 ft to 2860 ft, and pumping can be done now at periods of low power demand. The following facts about the Davis Creek watershed explain the 36-year reluctance to reach these, and other, benefits. Size: 3600 acres. Outline: roughly pear-shaped, 2 1/2 by 3 miles at the largest dimensions. Topography: mostly hill land with steep valleys. Relief : 760 minimum to 1153 maximum. Maximum rainfall: 3.36 in. per hour. Permanent water: none natural. Now 2200 gpm discharged through 16-in. drill hole from mine pumps underground. Geology: the 17 acres near dam centerline is Bonne Terre dolomite covered with sand and gravel eroded from Pleistocene beds that cap some of the hills. The remainder of the pond basin is on Davis shale. Soil cover: mostly second-growth timber with some abandoned fields; all subject to careless burning, which reduces water-retaining ability. Flood history: flash-flooding that had taken at least one life. Downstream values: two railroad bridges before creek intersection with Flat River. Immediately below confluence, a highway bridge, a low-water crossing, a few business establishments and several blocks of residences. In July 1942 the following segments of an ingenious plan were put into operation. A ditch 270 ft long, 16 ft wide and 5 1/2 ft deep was excavated to bedrock in the gravelly soil along the proposed dam's centerline. This excavation, which exposed many gravel-filled channels, was run full of slimes drawn from a riser set in the top of an adjacent tailings-disposal

Jan 1, 1947

By BLAllEY STEVENS

(Canal Zone Meeting, November, 1910.) I. INTRODUCTION. TEH object of this paper is to show how igneous intrusion is governed by definite mechanical laws. A distinction is made between dikes and fissures, and the various characteristics of intrusions are explained on an exact scientific basis. The modification of rock-stresses by intrusion is then considered and extensive isostress regions are recognized. Finally, a complete classification of intrusions is constructed covering all pos-sible cases. The generalizations of observed data, taken from Geikie's Textbook of Geology, conform to the laws of intrusion herein stated, and the deductions based upon these laws. No authority, however, is quoted for the type which I have named a corrugated intrusion. Its existence is a necessary deduction from the laws of intrusion, and even the entire absence of examples in technical publications cannot disprove its reality. In all probability, corrugated fissures would have remained undiscovered, but for the working of mineral veins. As intrusions of tabular form are seldom worked for commercial purposes, it has been left for theory to anticipate the discovery of corrugated dikes. In the light of these laws of intrusion and the corresponding laws of fissures,1 there seems to be a remarkable uniformity of stress-distribution in rocks at moderate depths. This renders .possible the mathematical calculation which should help us to approximate exact science in this and kindred branches of applied geology.

Jan 1, 1911

By F. Habashi

Lead is an ancient metal. The alchemists related it to the planet Saturn. It was largely obtained by smelting galena which generally contains small quantities of silver. That is why the metallurgy of lead was closely related to that of silver and in some cases the ore was treated only for its silver content. It was also known during the Roman time that lead vapors were toxic. Lead has been produced exclusively by pryrometallurgical methods. Lead refining is a complex process because of the presence of deleterious impurities such as arsenic, antimony, and bismuth. In the nineteenth century lead played an important role as a material of construction in the manufacture of sulfuric acid. In the twentieth century tetraethyl lead was used exclusively as an anti-knock reagent. In recent years lead is mainly used for making batteries.

Jan 1, 2008

The necessary funds have been provided for the award in 1915 of three prizes, respectively of $50, $30, and $20, for the best essays, or other papers, submitted in competition by Junior Members and Members of Affiliated Student Societies. The following rules for the competition are therefore established in accordance with the instructions of the Board of Directors May 22, 1914: (1) A competitor for the President's Prizes must be, at the time of submitting his essay, either a Junior Member or a Member of an Affiliated Student Society of this Institute.

Jan 1, 1917

By Tinto R

Aims of the Forum A contribution from Dr Robin Batterham, Vice President, RIO TINTO Research & Technology and a member of The AusIMM Standing Technology Advisory Qroup. Dr Robin Batterham is of view that the inevitability of automation in the minerals industry and the importance of addressing the human implications. He also outlined Rio Tinto's approach to automation. The progressive introduction of automation into mining operations will be revolutionary in its effects. This is the experience in other industries and it will be no different in mining. Mining companies most successful at implementing the new technologies will gain relative competitive advantage and those manufacturers who produce the most desirable automated equipment for miners will also gain market share.

Jan 1, 1997

The Warner Process has been devised to produce zinc metal directly from sulphide, thereby reducing the requirements for purchase of large amounts of energy in a special form. The process conditions for a practical process have been evaluated in an extensive program of research and development at the University of Birmingham. Recorded data now exists to take the process forward to commercial use within the next five years. The industrial economics have been evaluated. The cost of making zinc metal from zinc sulphide ore can be substantially lowered due to the reduced energy cost, locating zinc production in the neighbourhood of the mines and increasing ore to metal recoveries - particularly for fine-grained and pyritic ore. Integration of a Warner Furnace with a zinc mine and concentrator can result in a highly attractive return on capital Invested.

Jan 1, 1993

By A. A. Mathews

INTRODUCTION When Palmer King asked me to prepare a paper for this conference, it seemed quite appropriate, since I am Chairman of Subcommittee No. 4 of the U. S. National Committee on Tunneling Technology and we are presently making a detailed study of contracting practices. Before the end of this year, we expect to publish our report containing guidelines aimed at improving our contracting practices and minimizing the problems which develop therefrom. The American construction and mining industries today are glowing examples of the ingenuity of man pitting his wits against the unknown. Without the promise of rewards commensurate with the perils faced and the effort expended, it is doubtful that these industries could have reached their present state of advancement. Nevertheless, these industries are still primitive compared to many others such as aerospace and electronics. That our present contracting practices leave something to be desired is evidenced by the fact that many of our underground projects wind up with tremendous increases in estimated cost, financial disaster, and costly dispute and litigation. The situation is aggravated by the current economic uncertainty, energy crisis, and shortage of materials. At the same time, if our industries are to develop their maximum technologic potential, we must employ contracting practices which will encourage that development. Most of the contractual problems related to underground construction are associated with risk and its management. Unless all of the ramifications of this subject are understood, it will be difficult

Jan 1, 1974

By Abner Dixon

INTRODUCTION. IN India the production of mica, which in other countries is of very minor importance, is one of the staple, long established industries, and ranks high in the statistics of mineral products. Nearly two-thirds of the mica of commerce comes from India. The Indians have used mica for glazing and decorative purposes through many centuries. About 14,000 men are employed in and about the mines, and the indigenous and primitive mode of mining is still followed; but, by reason of the exhaustion of the surface supply hitherto won without intelligence or capital, it will not be many years before the present interesting and casual methods will be replaced by a less archaic and more profitable system. India on the whole has little mineral wealth, but the unique resources of its mica fields, cheap labor, and favorable natural conditions render it unlikely that any other country can ever more than temporarily contest her leadership in the production of this one minor but essential mineral. Mica plays a small but indispensable role in a variety of fields of dissimilar application. Its use and value depend upon characteristics which different kinds of mica have in varying degrees, each kind being adapted to 'its own special purpose. Its well-known characteristics of transparency, flexibility, elasticity, toughness, high dialectric, strength, perfect flatness; ease of splitting into thin films, ability to stand high heat and sudden changes in temperature, give it value in many industries. No other substance, natural or artificial, has this combination of qualities. The oldest use of mica is in glazing. By reason of the improvements in annealing glass, this is not now of great importance, but mica is still employed for the covers of ikon images in Russian churches, the windows of anthracite stoves, compass

Jan 5, 1913

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, minus what is taken up by the rivers and streams is suitable for settlement, and certainly two-thirds is good land. The gross area of the district is 2,417,299 acres. The principle rivers are the Wanganui, Mokau, Waitara, Patea and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").THE OIL-FIELDThe discription of an oil-field now-a-days usually resolves itself into a mass of figures and statistics, of great interest and value to the engineer and commercial man, but practically indigestible to the general public. It is the realm of the financierand the captain of industry.

Jan 1, 1912

"Cambior currently has nearly 80 exploration properties, acting as operator on about 60 of these. The company's exploration budget has increased to over $11,100,000 for 1990. On-going efforts recently yielded a new gold discovery on the Douay- Vezza property, a joint venture project with Inco and Vior. Cambior continues to seek out new opportunities, recently acquiring an option agreement on the Sleeping Giant project in Quebec and four new exploration agreements in the United States, through its Reno office. Other nearly-concluded joint venture agreements have also given the company entries into Indonesia and Guyana.SummaryWhen it acquired SOQUEM's assets on August I, 1986, Cambior also acquired interests in 45 exploration projects. The subsequent mergers with Aiguebelle Resources and Sullivan Mines in 1987 brought the total number of exploration projects to 83, most of which are concentrated in northwestern Quebec. Cambior's strategy emphasizes gold exploration, and exploration activities were, therefore, initially limited to the Val d'Or and Rouyn-Noranda mining camps, where Cambior has a large portfolio of properties. Approximately $25.8 million has been spent on surface exploration in this area since the formation of the company, resulting in the discovery of the Mouska deposit and four sub-economic zones on the Porcupine, Forbex, Bloc Sud and Flavrian project s. In 1988, Cambior became involved in projects in the United States to which the company expects to allocate about 38070 of its 1989 exploration budget."

Jan 1, 1990

By P. Hand

Most coal plants must run under conditions of varying feed conditions or are asked to produce qualities different from that used in the design. This can cause overloaded conditions as the ?bottlenecks? within the plant, depending on plant operation or as the feed changes. During plant design, geological information can be used to determine washability envelopes and blends that may be expected. Historical data can also be used to develop a size distribution envelope as well as to assign reasonable models for each of the unit processes. In operation, a plant can be sampled to determine changes and to refine process models. The information obtained can then be used in an accurate simulation to define how the plant can deal with the changing environment. This paper uses Limn: The Flowsheet Processor to simulate the coal plant in detail and will produce an accurate model, in terms of equipment sizing as well as water, medium, and solids balance, for each change in feed condition. It will show examples of running the simulation through complete density and size ranges and will determine the equipment required to address each part of the performance envelope.

Jan 1, 2010

By V. L. Eardley-Wilmot

Introduction We are all familiar with the bright and attractive colours of the roofs of our suburban houses and country cottages, but few of us fully appreciate the complex and highly technical nature of the business which produces these roofings. Roofing granules consist of small broken particles of certain types of rocks, burned clay products, or slag. They are used either in their natural state or artificially coloured and are affixed onto one surface of asphalt sheeting. Their main functions are to protect the roof against external fire hazard, prolong its life, and enable it to withstand extremes of weather over a period of years without deteriorating. Pleasing designs and colours are added attractions. The reverse, or inner side, of the sheeting is coated with a film of talc or fine mica to prevent it sticking when rolled up for convenience of handling for transport. The finished sheets or strips are cut into a variety of shapes for roofing shingles, or for sidings which resemble rows of bricks separated by mortar. In Canada, the consumption of roofing granules has increased fourfold in the past decade and indications are that the industry will continue to expand. At present, fourteen plants are engaged in manufacturing granule-coated roofings, but, apart from a relatively small output of natural granules by two producers in British Columbia, only one eastern producer makes both natural and coloured granules in Canada, and these only for its own use. The annual consumption is now over 77,000 tons of roofing granules valued at more than $1,600,000, but about 62 per cent of the tonnage is imported. It is thus apparent that the production of Canadian-made granules, both natural and coloured, could be considerably increased. This paper is presented in order to give an outline of the industry and at the same time to point out its difficulties and pitfalls.

Jan 1, 1946

By C. D. Kuchera

Ore crushing facilities at the Phelps Dodge Morenci Reduction Works became operational in January of 1942. This plant, with a capacity of 25,000 tons per day, was part of a project started some five years earlier with development of the Morenci Open Pit Copper Mine. In the following year, World War II's heavy copper demands prompted an 80% expansion in concentrating capacity to 45,000 tons per day resulting in a doubling of the secondary crushing plant. In the late 1950s and early 1960s, grinding capacity was again expanded to the present 60,000 TPD. This time the then 20 year old crushing plant was obliged to meet a 20% increase in production demand with no additional equipment. The ore, principally a medium hard monzonite porphyry, is dumped from 40 yard rail cars into an ore pocket over the primary crusher at a rate of approximately one car per minute. The primary crushing flowsheet, Figure 1, has remained essentially unchanged over the years. Equipment consists of a 40 by 16 foot grizzly set on a 40° incline and having 6" openings, a 60" gyratory crusher nomin¬ally set at 62" + 1" on the closed side and two 72" by 38' panfeeders which load crushed ore and grizzly undersize at a rate of 4,000 tons per hour onto a twin 54" belt conveyor system for delivery to the coarse ore bin. Ore is distributed across the bin by two single side discharge tripper cars. Bin capacity is extremely limited at 23,000 tons of which only 12,000 is available or "live".

Jan 1, 1975