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INTRODUCTION Much discussion has been generated over the years among geologists and engineers as to the ideal drill-hole configuration and spacing for evaluating various types of mineral deposits. Little can be found in the literature about the outcome of the programs, probably because of their subjective nature and the then lack of suitable means of scientific testing. In years past the drilling patterns and sequence were almost entirely determined by the experience and personal bias of the senior engineer, geologist, or project manager on the job. However, planning a drilling program- spacing, pattern, sequencing, etc.-is simply a specific case of sample design, or the design of a sampling program. Having been exposed in the preceding chapter to the theory of regionalized variables, and having learned something about the tools for measuring correlation, or lack of correlation, among samples within a given mineralogical population, we are now prepared to apply these concepts and new-found parameters to a scientifically designed mineral sampling program, be it by drilling or other means. FACTORS IN SAMPLING DESIGN It was shown in Chapter 8 that three major factors should be considered in any mineral

Jan 1, 1980

By Walter W. Fisher, Samuel Rudy

Secondary treated sewage effluent was substituted for normal process water in laboratory tests simulating froth flotation recovery of copper and molybdenum sulfides. Sewage effluent caused significant detrimental response in the flotation process. First, a voluminous, uncontrollable froth was generated, even in the absence of a frothing agent, that has little mineral carrying ability. Second, sewage effluent caused a small loss in copper recovery and a large loss in molybdenum recovery. The detrimental effects of sewage effluent on flotation were partially overcome by tertiary treatment of the effluent by activated carbon adsorption and anion exchange. The frothing problem was significantly reduced after treating the sewage effluent by foam fractionation. Dilution of the effluent with normal process water resulted in a significant improvement in metal recovery. In addition, the large loss in molybdenum recovery was overcome by using a secondary collector in a combination reagent schedule. However, the secondary collector caused an appreciable loss in copper recovery.

Jan 1, 1979

By B. K. Parekh, W. M. Goldberger

A novel process is proposed for continuous removal of ash and unreacted solids which become suspended in the oils obtained during coal liquefaction. The proposed method uses water in direct contact with the oil under conditions which cause the suspended residue solids to transfer from the oil to the water phase. Separation of the phases yields a product oil essentially free of suspended solids. The water is cooled, clarified or filtered by conventional low-cost systems, and recirculated. The paper describes experimental work leading to development of the novel concept and includes the result of batch experiments that establish the feasibility of the process.

Jan 1, 1980

By L. H. Hart

Because of a widely recognized association between breccia pipes of one form or another and many important copper deposits, conditions under which breccia pipes develop have been of great scientific interest for many years. Since these phenomena first attracted attention, many theories have been advanced to explain their origin. This is not unexpected, since it is likely that they have been formed by and under a wide range of conditions. Moreover, the entire subject is confused by the fact that the term breccia pipe is applied to a wide variety of occurrences. To discuss any part of the subject intelligently, therefore, it is necessary to start with definitions of the terms used. In their discussion of the Toquepala deposit, Richard and Courtright have carefully defined the terms they have used in their presentation of a very logical geo- logical history of Toquepala breccias. This is a real contribution, as there is no reference in the literature known to the writer where the history of a series of breccia pipe epochs, confined essentially within one channelway, may be read with the degree of certainty that appears to be possible at Toquepala.

Jan 6, 1958

Howland Bancroft (A Modern Approach To Foreign Mineral Development, P 666) was born in Denver, Colo and attended the University of Colorado, University of Michigan and received a B S and B A degree From 1907 to 1912 he was with U S Geological Survey In 1911 he was involved in study of mining resources of Peru Mr Bancroft resigned from Federal Survey and opened offices as consulting mining geologist in Denver in 1912 From 1919 to 1920 he was a consulting engineer in San Francisco He was manager of Sinclair Panama Oil Corp in Panama City in 1920 From 1921 to 1923 he was vice president and managing director of same corporation He did independent examinations in Western states and an exploration trip through Turkey in Asia from 1924 to 1925 Mr Bancroft was vice president and general manager of Lago Petroleum Corp in charge of operations in Venezuela Mr Bancroft has spent time in 34 different countries in the world and in a number of different Latin American States, Europe, Asia Minor and Africa

Jan 1, 1952

By Ben F. Dickerson

Mineral exploration programs have often experienced mismanagement in the decision-making process, and these errors have consequently resulted in stockholder losses. Unfortunately, the events leading to these errors are little known and rarely studied, since managers aren't prone to publicizing their mistakes. However, a bit of magnified hindsight may serve to identify some of the problems. It is interesting to note that there does not seem to be a generally agreed-upon definition of the role and function of exploration management. Several articles have addressed this subject, written by both academic and industry exploration personnel. Two apparent thought trends can be observed: First, the theoreticians insist that modern scientific management principles can be directly applied, without modification, to mineral exploration. However, when one searches for the rules, the proponents rapidly retreat behind the computers and talk learnedly of management information systems and game theory.

Jan 6, 1978

B. R. Coil (Electrical Installations at the Miami Mine are Cheaper with Flexible Cable, P. 356) was born in Higginsville, Mo., and attended McKinley High School and Missouri School of Mines. He received a B.S. in mining engineering. Mr. Coil has worked for the Braden Copper Co., Rancagua, Chile as junior engineer and foreman. He was employed by Miami Copper Co. as a jigger boss, shift boss, development engineer and mine foreman. He worked as mine superintendent and general superintendent of the Castle Dome Copper Company, Inc. Mr. Coil may be reached at Box 100, Miami, Ariz. He is an AIME Member. Mr. C. R. Ross was co-author with Mr. Coil in the preparation of this paper. His paper covers the present installation of electrical equipment in block caving stopes along with background data. In this paper he has given one solution to wiring problems in heavy stopes.

Jan 1, 1952

By Dae S. Young

A new probabilistic approach is introduced for slope stability analysis including adverse impact of blasting vibrations. The material strength within a slope area is randomized in this bi-variate joint probability analysis. To be a completely general engineering method, the new probabilistic approach employs the random variable transformation technique: the Hermite model of the Gaussian transformation function, which transforms the experimental histogram of strength values to the standard Gaussian variables. Because bi- normal joint probability is analyzed on the true probability region projected on the Gaussian transformed variable plane, it is an exact solution of slope stability based on the available sample data. Details of the probabilistic approach are given through a case study on an iron ore mine. The case study demonstrated that the probabilistic approach is effective and simple enough to be a routine engineering practice for slope analysis.

Jan 1, 1984

By Joseph P. Hodgson

JOSEPH P. HODGSON.-As to ".Safety First," I did not deal with that, but I will say that in 1913, the number of .men killed was nine, and that year the "safety first" program was commenced; the next year, 1914, the number was reduced to five. In 1915, I am pleased to say that the number was reduced to two in the Copper Queen's entire property, and we have none so far this year. THE CHAIRMAN (G. F. G. HERMAN, Bisbee, Ariz.).-I can say, further, that we have from eight to nineteen men per month incapacitated for more than 14 days. Those are classified in this State as serious accidents. The number of men injured has apparently increased, -but that is clue to our improved method of recording and classifying accidents, no matter how slight. C. W. GOODALE, Butte, Mont.-The importance of cooperation among the members of the staff of an industrial organization is well brought out by Mr..Hodgson's paper.

Jan 12, 1916

By C. H. Jacoby

Since salt, sodium chloride, is an essential mineral to animals and humans alike, the delineation of the salt deposits of the world has been continuous from prehistoric times. As man explores deeper into the crust of the earth, particularly in search of petroleum, numerous new deposits of salt have been recorded. This paper deals with the factors that equate the current economic value of a salt deposit. The value of a salt deposit is not only determined by the chemical purity of the sodium chloride, but also the method of extraction to be used, the use of the product, and/or the use of the deposit. Salt is basically an inexpensive industrial commodity where large tonnages must be available to conduct a successful mining operation. Therefore, not only must the deposit contain these large tonnages, but also it must be accessible and transported as low cost freight to a large market. The geological environmental conditions surrounding the deposit must be such that it will be conducive to low cost mining operations. These conditions include not only the depth, size, shape, and internal structure of the deposit, but also the characteristics and extent of the overlying ground water.

Jan 1, 1973

By D. W. Frommer

Processing nonmagnetic taconites by selective flocculation-desliming and flotation requires large volumes of water. If impounded without treatment the effluents from these processes require excessively large areas for containment. Experiments conducted in the Bureau of Mines 900-lb-per hr pilot plant at the Twin Cities Metallurgy Research Center indicates that approximately 85% of the water needed to process Michigan nonmagnetic taconite could be reclaimed from the process itself. Water was reclaimed by the controlled addition of lime, sodium carbonate, and synthetic flocculant. As a result, turbidities were reduced to ?1000 ppm equivalent SiO2, while a Ca ion content of ?16 ppm was maintained in the finished effluent. Good-quality flotation concentrates were obtained with reclaimed water and, by means of some indirect comparisons, it can be concluded that the reuse of the water permits a savings of almost 2.0 lb per ton of NaOH, and probably as much as 0.25 lb per ton of fatty acid for total savings of 7.8-10.3 cents per ton of feed. These savings are nearly offset by an estimated chemical cost of 9.3[c] per ton for water treatment.

Jan 1, 1970

By Thomas N. Walthier

Ocean miners seem prepared to commit upwards of $50 million, spread over the next 10 years, to develop a deep ocean capability. More and more large companies, Kennecott, Inco and Tenneco, to name a few, singly or through consortia, are spending money, often big money, to obtain a viable and profitable marine mining industry. Much of the current involvement of the mining industry in the oceans is concerned with either exploration for or engineering studies of manganese nodule deposits and most of it is considered highly proprietary. Thus, the scope of the total effort can only be surmised. The following provide a good indication as to the magnitude of the over-all effort: (1) Hughes Tool Co., Oil Tool Division, announced last March it has been performing engineering studies and ocean surveys (in collaboration with Global Marine, a subsidiary of Tenneco Oil) for the purpose of developing deep ocean mining equipment and techniques. As a result of these studies, Global Marine will build a 35,000-ton prototype deep sea mining ship for Hughes. (2) Deepsea Ventures, Inc. has been "assiduously compiling data on the location. depth, and composi-

Jan 1, 1971

By C. B. Barlow, T. A. Mekelburg

Due to a tight ash constraint on the clean coal product and difficult middlings washability characteristics, a considerable amount of coal was being lost in the jig middlings at the Monterey No. 2 Mine. An investigation was conducted into circuitry to recover this lost coal with minimal effect on the total clean coal ash. A reverse two-stage hydrocyclone system cleaning at low specific gravities was selected. This system is currently recovering approximately 5.8 kg/s (23 stph) of 11.5% to 12.5% ash coal. The specific gravity of separation for the system is about 1.5 and the probable error is 0.13.

Jan 1, 1986

By Helen L. Cannon

BOTANICAL methods of prospecting for metalliferous ores are based on the premise that deposits at depth may be reflected chemically in surface vegetation. For the past several years, on behalf of the Atomic Energy Commission, the U. S. Geological Survey has investigated on the Colorado Plateau the application of botanical methods to uranium prospecting. Results suggest that orebodies may be found under a considerable cover of barren sandstone through the absorption of uranium and associated trace elements by plants growing at the ground surface. Plant physiologists have demonstrated that uranium is a necessary nutrient for plant growth and therefore is present in all plants.' The amount present is small but measurable. The absorption of uranium by plants growing over ore deposits forms

Jan 1, 1955

By A. Bentzen, S. S. Wong, W. K. Fletcher, B. J. Price, A. J. Sinclair

One hundred eleven pyrite samples from three porphyry-type deposits in the Canadian Cordillera were analyzed (many in duplicate) by AA spectrophotometry for Co, Ni, Cu, Pb, Zn and Mn. All elements have density distributions that are lognormal or combinations of lognormal populations. Co and Ni in pyrites show zonal patterns that relate generally to mineralogical zones in the porphyry systems, particularly if contoured as the Co/Ni ratio. High Cu and Mn values in pyrites also correlate with Cu-rich mineralogical zones. Other elements studied appear less regular in their distribution patterns, although Pb and Zn highs in pyrite seem to occur sporadically near the margins of porphyry systems. These data considered with two other studies permit construction of an empirical model for the distribution of certain minor elements of pyrites from porphyry systems of the calc-alkalic suite. In particular cases pyrite geochemistry shows potential as an exploration tool to aid in target definition for detailed exploration.

Jan 1, 1978

By Robert E. Snow, Douglas J. Cosler

The application and development of computer models for simulation of transient ground water inflow to underground mines can assist in mine planning and operation as well as environmental impact assessment. Applications include planning for water handling, treatment, and disposal operations based on predicted mine inflow rates, determination of mining impacts on ground water movement and potentiometric surfaces in neighboring aquifers, evaluation of methods for minimizing ground water inflow, and determination of ground water inflow quality. The potential ground water inflow components to a mine consist of direct inflow from an adjacent aquifer and infiltration through intervening geologic formations. The rates of inflow are controlled by the geologic conditions, the potentiometric surface of the aquifer, and the hydrogeologic characteristics of the water-bearing and confining formations. The capabilities and potential use of a computer model for simulation of mine inflow are illustrated through an example problem.

Jan 1, 1983

By Thomas M. Dr. Drown

IN experimenting in connection with Mr. P. W. Shimer (now chemist of the Thomas Iron Company, Hokendauqua, Pa.) on methods for the determination of silicon in pig iron, in order to find one which should be accurate and yet give results in a few hours, I have adopted the following procedure, which, as far as my experience goes, leaves nothing to be desired. About one gram of pig iron or steel is treated in a platinum or porcelain dish with 25 cubic centimeters of nitric acid (sp. gr. 1, 2). When action has ceased, 25 to 30 cubic centimeters of dilute sulphuric acid (one of acid and three of water) are added, and heat applied until the nitric acid is nearly or quite driven off. The heat of a water-bath is sufficient, though the process may be hastened by heating higher on a sand-bath. Water is then cautiously added (as soon as the free sulphuric acid is sufficiently cool) and the contents of the dish heated until the crystals of ferric sulphate are completely dissolved. The solution is then filtered as hot as possible, the residue washed first with hot water, then with 25 to 30 cubic centimeters of hydrochloric acid (sp. gr. 1, 12), and finally with hot water. After drying and igniting, the silica will be found to be snow-white and granular. The following are some results obtained by this method compared

Jan 1, 1879

By M. W. Cox, V. F. Hollister

Exploration for metallic mineral deposits is carried on by those special adaptations of methods which the explorer believes will yield most economically or satisfactorily the particular answer sought. In this project the usual methods of geologic observation, recording, and interpretation, when combined with magnetic geophysical methods and geochemical soil sampling, led to disclosures of appreciable zinc mineralization where none was visible in surface exposure. Since 1945 considerable work has been done with geochemical prospecting methods, chiefly in determining the presence and distribution of various elements existing in minor amounts in rocks, soil, vegetation or waters of mineralized areas. Such work, in which the U. S. Geological Survey has taken the lead, finds a ready place in the field repertoire of the exploration geologist as a supplement, not a substitute, for other methods. The Chollet project was carried out in 1951 by the American Smelting & Refining Co. near its Van Stone mine in northern Stevens County, Wash., in the area shown in Fig. 1

Oct 1, 1955

By W. F. Pruden

On June 30, 1960, ground was broken for the construction of the facilities to mine, concentrate, and agglomerate the iron ores of the Atlantic City, Wyo., area which has become known as the "Atlantic City Project." This was a historic occasion for Columbia-Geneva Steel Division of United States Steel Corp. When completed, the installation will be the first integrated iron ore beneficiation plant west of the Mississippi River producing an agglomerated product. This Project, named for a nearby ghost mining town, is located in central Wyoming on the south-east flank of the Wind River Mountains. It is 16 miles north of the South Pass, where the early pioneers who followed the Mormon and Oregon Trails crossed the Continental Divide. White men first penetrated into this area in October, 1812, when Robert Stuart Party brought the returning Astorians through South Pass on route to St. Louis from the Columbia River area. Further interest in the area developed when gold was discovered in the sands of Rock Creek and the towns of Atlantic City and South Pass City were founded.

Jan 5, 1961

By Charles E. Wait

In the use of the apparatus purchased for the new chemical laboratories of the university, no piece has given us more satisfaction, or has been a greater success, than a new still which is the subject of this paper. In the designing of this still I had two definite objects in view ; one, the utilizing of steam from the large 60 horse-power boiler used in heating the building, and the other, a provision for making distilled water with gas, when steam from the heating-plant was not available. The still is encased in wrought-iron, with a lining of asbestos, and is provided with a float which automatically regulates the flow of water from the supply-pipe. It was made for me by G. J. M?rrle, Pforzheim, Germany, and was imported by Messrs. Eimer & Amend, of New York City. It is a beautiful piece of apparatus, and the workmanship is excellent in every detail. The essential parts of this apparatus will be understood by consulting the accompanying figures, but a few words of explanation may be appropriate. The still has a capacity of seven gallons, and is made of heavy copper, tin-lined. It has a water-gauge showing the height of the water in the still, also an exit for steam, and safetyvalve, V; inlet for steam through a coiled perforated block-tin pipe; also an outlet, 0, for cleaning out the still; and there is also a heavy

Jan 1, 1895