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Research 86 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information 2401 E Street, NW., Washington, DC 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1986

By J. E. Ostberg, G. Phragmen, A. Hultgren, S. Wohlfahrt

Detailed study was made of a number of rimming ingots, both low and high carbon, and especially upon effects of superimposed air pressure. Requirement to suppress core bubbles is between 10 and 15 atm; at 6.5 atm freezing was in semikilled manner and at 3 atm, steel was of rising type. Probable mechanism of freezing under various conditions is discussed. AN earlier paper' reported an investigation made by a committee for studying rimming steel ingots appointed by Jernkontorets in Stockholm. The present paper is the outcome of some further work done by the same committee. Since the characteristics of ordinary rimming steel are connected closely .with the amount of gas liberated during freezing and since this amount of gas is governed by the pressure, it was considered of interest to ascertain in what manner and to what extent definite pressures applied to the top of the liquid steel in the mold would affect the solidification process and the consequent structure of a rimming steel of ordinary composition. The experiments were made at the Domnarfvets Steel Works. The steel was made according to normal practice in a 4-ton Rennerfelt electric furnace. Ferromanganese was added in the furnace; no aluminum was added, with one exception. Analyses of the four heats are given in Table I. The top-poured ingots measured about 12 in. sq x 48 in. and weighed about 1300 lb. One or two ingots of each heat were allowed to solidify under pressure, using a special device for admitting compressed air to the upper closed part of the mold, as shown in Fig. 1. A heavy plate sealed with asbestos was bolted to the top of the mold. The plate had a tapered aperture for pouring. Immediately after pouring the hole was closed by a wedged plug, and compressed air was admitted through a hole in the plug. Because of some delay in applying the plug, full pressure was not reached immediately. The pressure was adjusted to the desired value as indicated by a manometer. In order that the interior of the ingot might have the benefit of the pressure, the freezing of the top crust was delayed by a refractory lining applied to the top part of the mold, Fig. 1. Ingots were also cast from each heat without applied pressure, and with and without refractory lining at the top. Axial sections of ingots were cut either of the whole ingot or of some part of it of special interest; sections were polished and usually etched.' To facilitate description of structures the following terms may be used for different types of ingots solidified under gas evolution: 1. Box-hat or boot-leg ingot: Abundant gas evolution during casting and during rimming; no rim holes. 2. Normal rimming ingot: Lively gas evolution during rimming; usually rim holes in lowest part of

Jan 1, 1952

By Jeff Wilkinson, Brandon Walter

"A&N Electrical Cooperative provides electrical service to the counties of Accomack and Northampton along Virginia’s Eastern Shore and to Smith Island in Somerset County, Md.A&N recently worked to improve the efficiency of power distribution to a small island community and marina on Tangier Island in the Chesapeake Bay. This improvement consisted of upgrading the existing distribution substation with a new 25 kV 2-bay box distribution structure. Earth Contact Products (ECP) collaborated with PowerServices, Inc. (PSI) to design and install a helical foundation support system as part of the substation upgrade. Feasibility EvaluationThroughout the design process, A&Nworked with its partners PSI (design) andT&D Solutions (installation) to identifycost-effective alternatives. Foundationsystems considered included cast-in-placereinforced concrete caissons, precastconcrete foundations, driven steel piles and helical piles. In evaluating all of theoptions, the greatest concern was gettingthe material onto the island, followedclosely by the availability of the equipmentto install the foundations. Clearly, cost,more specifically the installed cost, was asignificant consideration and decisionfactor throughout the process.There were several limiting factors that had to be considered during the design process, the most significant of which was that all of the material had to be barged to the site. With traditional reinforced concrete deep foundations in mind, the cost for installing these piles was projected to be nearly $2,000/cu yd ($262/cu m) of installed concrete. Given that approximately 5 to 6 cu yd (3.8 to 4.6 cu m) of concrete would be required for this structure, the cost was significantly high for this project. What’s more, because the components of the concrete mix would have to be barged and then hand mixed on site, there was concern regarding both the time required to complete the piles and the quality of the installed concrete. For the driven pile alternative, the availability, or lack thereof, of equipment and material cost resulted in a total cost estimate that was more expensive than that of the concrete piling alternative. The high material cost for the piles, which was more than double than the cost of concrete, was due to the number and size of piles needed to resist the overturning moment. Ultimately, the team selected the helical pile alternative. The decision to a use helical pile foundation system was based on many factors, not the least of which was the remote location of the project site and the difficulties associated with getting material, equipment and construction personnel to the project site."

Jan 1, 2017

By K-A. Adamson

If fuel cells and hydrogen are to become a mass market reality a substantial amount of further research and development needs to be undertaken. Work in hydrogen storage, production, the economics of all aspects of fuel cells and hydrogen, materials balances, and product integration are just a few of the areas that are under focus. Setting R&D targets, and providing R&D funding are therefore areas that are central to the long term development of the market, and areas in which a number of governments worldwide are highly active. Some governments, such as Japan and Korea, have set a number of very ambitious, highly focused, long term targets and are backing this up with substantial funding, others such as the EU are working on a more integrated approach, wrapping some fairly fundamental R&D into large integrated projects which run in combination with a number of other market aspects, such as public acceptance and roadmapping. The US is slightly different, in that although is has a number of long term programmes and targets, FreedomCar and SuperGen being just two, the levels of funding are set annually with the passing of each years Fiscal Budget. This paper takes three high profile regions and analyses the R&D targets and funding levels for fuel cells and hydrogen. Criteria that will be looked at include: Time frame of target(s), level of ambition, funding issues, including: Funding windows, levels available, funding barriers, overall programme goals. The added value to this paper is that it will provide a clearer picture of where each region is heading, what are its strengths and weaknesses, in terms of R&D and where there may be areas for potential international collaboration.

Jan 1, 2005

By Manuel Diaz

"In these difficult times for the mining world, mainly due to the global uncertainty about metal prices and the increased activity of opponents to the mining industry, it is essential that mining companies focus on efforts and strategies that will give them the most flexibility to succeed under the fury of these phenomena. The careful management of systems to control costs, and indicators to measure with great precision actual variations in costs and cash flows, are essential to adequately manage the uncertainty. Similarly, clear corporate and regional strategies designed to maximize cash flow and operating margin will allow the company to be better prepared to face any negative situations caused by declining metals prices, stricter government regulations and increasing social pressure. Gold Fields Limited, a corporation of South African origin and with more than 100 years in the gold mining business, has developed the ability to adapt to large changes generated by different global crisis throughout its history. This occasion will be no different. Given the critical situation of the mining industry in the world today, Gold Fields has embarked on a re-structuring plan at global level that will allow much closer control and real efficiency of production costs. This plan includes the creation of regional business units that allow greater independence for each region while still preserving the standards and cultural values of the Corporation. This presentation will explain why we believe that this approach combines the best aspects of the two styles of business, and what are the expected results. In the Americas Region, Gold Fields currently operates Cerro Corona, in Peru. In addition, the company is considering opportunities for growth in Chile, Brazil, Mexico and Canada."

Jan 1, 2014

By W. D. Musgrove, B. W. Gandrud, A. C. Richardson

"INTRODUCTION The Cahaba coal field is the second largest coal—producing area in Alabama. This field underlies parts of Shelby, Jefferson, St. Clair, and Bibb Counties and has an area of about 270 square miles. The Cahaba formations contain a number of coal beds, about 8 of which are mined at present. Although the area contains many folds and faults, samples from various mines and beds indicate that, except for the variation in ash content, the coal from this field is very uniform in character and quality. It is a high-volatile bituminous coal used chiefly for steam-raising purposes and domestic fuel. The coal as mined usually contains too high a percentage of impurities to be marketed without some preparation. The majority of the mines have washing plants in which jigs are the favorite type of equipment, although at some mines tables are used for cleaning the slack sizes. The washing characteristics of the coal from the Cahaba field are very uniform and differ from those of the near-by Warrior field, in that the coarser sizes contain a much lower percentage of bony material than the finer sizes. In general, the bone increases with decrease in size. It breaks into thin flakes, making difficult its elimination in the cleaning process, and gives rise to what is known among the washery operators of the Cahaba field as the ""rash problem.""A previous publication 5 referred to rash from the standpoint of jig operation and suggested some means of handling it with jigs. This report presents the results of table tests on two samples of fine coal from the Thompson and Woodstock beds, respectively, of the Cahaba field to determine the influence of rash on table efficiency.This investigation has been made in connection with the study of coal-washing problems now being conducted by the U.S. Bureau of Mines and the University of Alabama, with the cooperation of the different coal operators of Alabama."

May 1, 1934

A. Cook K.A. Grace's article advocates usage of the terms describing resources as defined by the US Bureau of Mines (USBM) and the US Geological Survey (USGS). Originally recommended in 1943, the terms were revised in 1976 and again in 1980. Mr. Grace further recommends that the term reserves should be severely restricted and that it should encompass mining and processing factors. The list of references quoted in the article does not, however, mention the study concerning reserves that was made over a period of almost four years by a joint Committee on Definitions. This committee was sponsored by three societies - the American Institute of Mining, Metallurgical, and Petroleum Engineers (AIME), the Society of Economic Geologists (SEG), and the American Institute of Professional Geologists (AIPG). Most of the detailed work was done by a working party appointed by the Society of Mining Engineers (SME) of AIME. After studying previous definitions in the US as well as in the United Kingdom, Canada, Australia, France, and other European countries, the following definitions were proposed and accepted in 1974 by the SME board of directors. (Ore reserve definitions in Rhodesia, South Africa, or New Zealand were not mentioned as having been reviewed. Table 1 lists definitions from MINING ENGINEERING, July 1975. Notice in Table 1 it was mentioned, under Resources, that the definitions of reserves were recommended for the purposes of commercial evaluation. It was further stated that the terminology adopted by the USBM and the USGS, as released to the public, covering resources, was recognized as such. Mr. Grace also recommends that reserve calculations should allow for future losses in ore tonnage, ore grade, milling, and smelting. Unfortunately, it might take years to develop a prospect after it has been discovered. Mining methods have to be tested before being finalized in order to know what tonnage of ore is going to be lost, or how much dilution is likely to occur. The same problems are present in concentrating or in smelting. Operating mines usually know how mined grade compares with ore reserve grade. They can usually predict fairly closely what their final metal recoveries are probably going to be. It is, however, expecting too much to have to delay quoting reserves from say a recently drilled prospect. Any responsible mining geologist or mining engineer (or company for that matter) should state several things about an ore reserve calculation: that it is or is not a preliminary estimate only; that estimated grades have not been diluted to allow for a future, as yet unknown, mining method; that metal recoveries are or are not only tentative, based perhaps on drill hole samples only or on no metallurgical testing at all. [ ] Reserves of a partially explored prospect are always quoted when it becomes necessary to raise capital. If they are described as preliminary only (really just tonnage and grade estimates and not true "reserves") in addition to being accompanied by some of the items just mentioned, nobody is going to be misled. If, on the other hand, a report by a member of the SME or SEG is intentionally misleading, the individual must be reported and eventually disbarred from his or her society. To summarize, let us stay with the definitions of ore, ore reserves, and related terms as recommended and accepted by SME. I might add that on occasion I have used a fourth category in my ore reserve calculations, namely Geologically Possible Ore. This category is more or less the same as Inferred ore defined by the USBM and USGS. I have never given a grade to this category, which may be based only on geological mapping, geochemical sampling, or geophysical traversing. ?

Jan 1, 1986

By R. Kent Comann

Introduction This article describes ways to maximize employment potential for those looking for a job in the minerals industry. Advice on the right way to prepare a resume is followed by tips on where and how to look for a job and ways to make the best of an interview. Information on current salaries is also included. RESUME NAME: Give home and college addresses and telephone numbers, ADDRESS: if still in school. Otherwise, give home address and TELEPHONE: telephone plus business telephone number. JOB OBJECTIVE: What do you want to do? EDUCATION: List degree(s), name of college(s), location(s), and date(s) degree(s) received or to be awarded. Do not list your high school but do include postgraduate education, training, or seminars. WORK EXPERIENCE: List your most recent experience first, and the rest in reverse chronological order. Include dates (month and year) and company names. First show the entire time spent with each employer, then list the various jobs (with dates and duties) you may have had with this employer. MILITARY SERVICE: List dates, branch of service, and duties. If you did not serve, delete this section. COLLEGE ACTIVITIES: Show organizations, sports, and offices held. Only list these if you are a graduating senior, otherwise delete this section. PERSONAL DATA: List age, marital status, height, weight (optional), foreign languages spoken, professional memberships, and health (if good or excellent, otherwise do not mention it in the resume). If you prefer a certain location and would not accept a job anywhere else, list the location desired. Otherwise, do not restrict yourself. Also list special skills, hobbies, or interests that will help sell you to the company. Be brief in this section and use good judgement as to what you say. REFERENCES: Furnished on request. Resume Guidelines There are some things to remember when preparing a resume. These include: • Limit your resume to one page, unless you have a lot of experience. Then it should be a maximum of two pages. • Use 8.5 x 11 plain bond paper, white or off-white. Stay away from colored paper, odd size paper, and cute resumes. They are counter-productive. • Make certain your resume is typed professionally. Be sure to check for spelling, grammar, and typographical errors. • Have your resume reproduced by copier or printing shop. Do not use carbon copies. • Keep your sentences and remarks short and punchy. Use action verbs. • Have a good layout that is easy to read, brief, and uncluttered. Allow some white space in your resume. There are also some things you should not do when preparing a resume. These include the following: • Do not include a photograph or mention your religion, race, or sex. • Do not leave gaps of time unaccounted for in your resume. • Do not include your college transcripts with your resume or list all the courses you took in college. • Do not list all the articles you have written. Only list one or two, if appropriate for, say, a research and development job. • Do not include reference letters with your resume. Any good, prospective employer will make telephone reference checks. • Do not use "Curriculum Vitae," use "Resume." • Do not include unnecessary data such as your social security number, passport number, or PE registration number. If you are a PE or EIT, be sure to mention that in your resume. Do not mention US citizenship or US work permit unless you have a foreign education or are not a native US citizen. • Do not include present salary or salary requirements. This will come out in the interview. • Do not use the word "I" in your resume or refer to yourself in the third person. • Do not lie, distort, exaggerate, or editorialize in your resume. • Do not have your resume prepared by an outside resume service. This is unnecessary, costly, and generally not effective.

Jan 2, 1985

By Paul B. Crawford, Bobby L. Landrum

Electrical model studies have been made of the effect of drainhole drilling on production capacity. Drain holes are those lateral holes which are sometimes drilled to assist in increasing the oil drainage into the main wellbore. The studies indicate that if the drainhole length i.r near 0.2 of the drainage radius, the increase in production capacity may be approximately 1.8, 2.08, trnd 2.33 for the case of one, two and four drain holes, respectively. If multiple drain holes are drilled, shorter holes are required to achieve a specific increase in production capacity than if one or two holes are drilled. To achieve increases in production capacities by factors near three it is shown that the drainhole lengths divided by the drainage radii must be approximately 0.64, 0.48, cnd 0.37 for the case of one, two and four drain holes, respectively. IN T RO DUCTION Kecent developments in drilling techniques have permitted the drilling of lateral or horizontal holes to increase the rate of production. The number of these drain holes may vary from 1 to 10, and they have been drilled laterally as much as 100 ft. Drainhole drilling at substantial depths is of recent origin but has been used in the Spraberry field of West Texas, the La Pas field in Western Venezuela, and certain fields in California. The diameter of the drain holes has been approximately 6 in. In drilling drain holes it is desired to know how much increase in production capacity may be expected, what additional benefit may be gained by drilling more than one drain hole, and what increase in production capacity may be brought about by lengthening the existing drain holes. In realization of the importance of lateral drilling, electrical model studies were made to provide quantitative estimates on the effect of drain holes on production capacity. ANALYSIS An electrical model was used in studying this problem. A wooden circular reservoir approximately 30 in. in diameter and 2 in. deep was filled with a dilute salt solution to a depth of 1 in. A copper band formed the periphery of the tank, and a copper wire was inserted in the center of the tank to represent the well. The drainage radius divided by the well radius was equal to 500. A diagram of this type model is shown in the inset of Fig. 1. An electrical potential was applied to the wire well and copper band at the periphery to determine the flow of current. Following this measurement copper wires of various length were soldered to the vertical wire well in such a manner as to simulate lateral wells drilled into the reservoir. Multiple lateral holes of various lengths were studied by varying the number and length of copper wires soldered to the vertical wire well. All multiple lateral wells were located symmetrically about the vertical well. The effect on production capacity by drilling an infinite number of lateral holes was studied by replacing the lateral hole with a copper disk. For each condition the flow of current was measured and compared with the flow of the vertical well only. The model which is thus described provides the steady state increases in production capacity which may be expected in some cases. The data conform to those which would be observed for a uniform homogeneous reservoir. The data may have primary application to those reservoirs producing above the bubble point. It is realized that few lateral holes are drilled in reservoirs of this type, but the data may be of some value in guiding future work or aiding to explain observed phenomena.

Jan 1, 1956

By T. H. Butler

The two most talked of questions in the mining industry today are rock dusting and mechanical loading. The one as a matter of safety, and the other as a matter of economy, and both are of vital interest to the mining fraternity. Rock dusting and other safety methods will be dealt with by others at this meeting, so I will confine my few remarks to the matter of mechanical loading. I will not attempt to tell you what mechanical loaders are doing in the different mining fields throughout the country, or what they should do, but will endeavor to give you an outline of the work being done with mechanical loaders in No. 4 Mine of the Union Pacific Coal Company, at Hanna, Wye. In order that you may better understand and be in a position to follow me it will be necessary to cite the conditions under which we are working. and the type of loaders in use. The seam pitches from 14 to 17 degrees, and is normally 32 feet in thickness, and is overlaid with a soft sandstone roof. The panel system of working is used, planes being driven on the pitch, and rooms driven on the strike. Owing to faults being encountered planes are driven between the faults, and the. rooms on either side are in some instances 800 to 1,000 feet in depth. Rooms are advanced eight feet in height, and 32 feet in width, by hand loaders and .Toy mechanical loaders, and when driven to the boundary,, 18 feet of the remaining 24 is loaded out with Thew electric shovels, and six feet left to protect the roof. In January, 1916 the company installed a Type 1 Thew shovel, equipped with a 1 1/4-yard dipper, and in July, 1917, they installed a Type 0 Thew electric shovel, equipped with a 1-yard dipper, and in the year 1918 two additional Type 0 Thew shovels, equipped with a 1-yard dipper, were installed, making a total of four Thew shovels for this mine. The introduction of these shovels caused the employees much concern, and like all departures from the old methods of mining, met with indifference by some and open antagonism by others, so that for some time they results obtained were not satisfactory. However, by constant supervision and changes in the method of haulage the results obtained at present, while not entirely satisfactory, are much better and the production and costs are reasonably good. The Thew shovels in use are mounted on traction wheels with swivel axle and move. in all directions by their own power, and while the weight of each is approxi¬mately 20 tons, they are not as cumbersome as. one would think and are easily operated. The system used in working these shovels is to shoot the coal clown ahead of the shovels and maintain two tracks, two cars being used on each track so that shovel is loading on one track while driver is, changing cars on the other. When place is finished the shovel is run back to the first cross-cut by its own power and lowered to the next room with block and tackle, the roof coal in cross-cut being shot down to a height of 16 feet to allow passage of the boom. With better results from the Thew shovels we soon realized that it was necessary to find some method of developing rooms faster than was being done with hand loaders in order to keep the Thew shovels in working places, and in November, 1923, the company purchased from the Joy Machine Company two Type 4 B U Joy loaders, and the installation of same met with the same indifference and antagonism from the employees as did the Thew

Jan 1, 1924

By Earl G. Hoover, V. S. Znamensky

For most geologists and miners the term asbestos refers to a group of highly fibrous silicate minerals that readily separate into long, thin, strong fibers of sufficient flexibility to be woven; these fibers are heat resistant and chemically inert, and possess a high electric insulation and therefore are suitable for uses where incombustible, nonconductive or chemically resistant material is required. The US Mining Safety and Health Administration (MSHA) specifically refers to the naturally occurring minerals chrysotile, amosite, crocidolite, termolite asbestos, anthophyllite asbestos, and actinolite asbestos as asbestos if the individual crystal fragments have the following dimensions: length-greater than 5 µm; maximum diameter-less than 5 µm; and a length to diameter ratio of 3 or greater. Since asbestos has been identified as one of the ten most carcinogenic substances (a cancer-causing agent), it has become, for many government regulatory agencies, a major issue concerning banning emissions to the environment. Very few recent issues have caused as much concern for the crushed stone industry as asbestos. Complicating the problem is the fact that several federal and state bureaus have greatly compounded the confusion because each has become involved in the asbestos dilemma. Simple solutions to a very complex problem have been proposed by these various governmental groups. In addition to governmental bungling is the fact that public interest groups have been able to use federal and state laws that have been enacted with a strong environmental bias to foment even greater complexities. Such is now the state of the asbestos problem. No con- firmed health risk has been associated with low-level exposure, namely crushed stone in an unbound form; a methodology for sampling and analyzing for asbestos has not been developed; a precise definition of what is asbestos does not exist, nor does a concensus among the various government groups as to what course of action to pursue. Pure asbestos as it is mined for commercial purposes does not exist in the properties mined by the crushed stone industry. Where the six asbestiform minerals do appear (to date we've been referring mainly to chrysotile in serpentinite formations in Maryland) the amount of the asbestiform mineral present is generally quite small. They generally appear in scattered, miniscule amounts. In the case of Rockville Crushed Stone in Montgomery county, Mary- land, the chrysotile is less than 1/2 of 1% of the rock deposit. No health risk has been identified with such minute quantities of asbestos minerals. MSHA standards for the occupational health and safety of quarry workers are being met; and there is every indication that normal background levels of asbestos, throughout the surrounding countryside, are as high or higher than levels measured on roads where the rock is used in pavement or base. The problem and the controversy lie with improper terminology on the part of so-called public interest environmental groups, aided and abetted by some governmental agencies who, to be charitable, we can best describe as uninformed. The news media frequently has fanned the issue, unintentionally we'd like to think, by quoting these misinformed authorities and not bothering to question the facts or adequately report balancing information handed to them. It is much better copy to talk about an asbestos cancer scare, than to deal with rather mundane measurements and descriptions that are hard to understand. At the heart of the issue is the improper use of the word asbestos. Instead of being confined to the geological description of the six asbestiform minerals-chrysotile, amosite, crocidolite, termolite asbestos, anthophyllite asbestos, and actinolite asbestos-the word asbestos is also wrongly used, but too-frequently to identify many other minerals that happen to have elon-

Jan 1, 1986

By D. L. Everhart

The search for new deposits raises two important questions: Where did the metallic ions that formed the orebodies come from? What processes and geologic factors were involved in ore replacement? A review of the wide geological variety of recent uranium discoveries tells how these questions are being answered. SOONER or later intelligent exploration for uranium leads to these questions: Where did the metallic ions that formed the orebodies come from? What processes and geologic factors were involved in ore replacement? These matters, of course, make a big difference in how best to look for orebodies. Before these questions are discussed it might be well to point out other factors bearing on the subject. The whole business of uranium exploration is only a little over ten years old, participation by the public is only about six years old, and real interest and activity by more than a few large mining companies has arisen only in the past two or three years. Throughout this short period, uranium exploration has been affected by the unique influences of necessary security measures and by division of the overall job into individual projects by a large number of specialists in diverse fields. This has meant that a normal interchange of information on the nature of uranium deposits has really only just begun. Compared to the vast amount of published studies on iron, copper, lead, zinc, and gold deposits over the past 50 to 75 years, current knowledge of uranium deposits is in its infancy and much of the pertinent information is still scattered about in a number of unpublished sources. The volume of reports on all phases of uranium exploration is now beginning to mount at a remarkable rate, and geologists with widely varying specialized backgrounds in uranium geology are engaging in spirited debates over the origin of uranium and the relative importance of geologic controls of various deposits. One of the most interesting features of known uranium deposits of the world is the wide variation, see Table I, in character and geologic environment. It should be noted that many types became prominent during 1953. The davidite-bearing veins of Radium Hill, South Australia, are almost unique, although the same mineral occurs in a different kind of deposit in Mozambique. Recent studies indicate that brannerite disseminated in the granite near Cracker's Well, South Australia, may soon constitute uranium ore. Basalt has been added to the list of favorable host rocks in the Northern Territory of Australia. Basalt is also the host of the pitchblende veins of the Martin Lake deposit, Beaverlodge district, Saskatchewan. The truly remarkable rich and extensive Steen deposit near Moab, Utah, is of the uraninite-vanadium oxide type. Secondary hydrous uranium arsenates and phosphates constitute the uranium minerals in the disseminated deposits of the Wind River Basin, Wyo., a new district discovered in the summer of 1953. Uranium minerals in shales adjacent to fractures were newly reported in New Mexico and several other parts of the world during the year. The well-known important uraninite dissemination in the Rand conglomerates of South Africa has a counterpart, as discovered in the summer of 1953, in the Mississagi quartzite and conglomerate of the Blind River district, Ontario. Gunnar deposit of the Lake Athabaska district, Saskatchewan, consists of uraninite in both granite and sedimentary gneiss beneath a granite cap, and large new orebody of the Eldorado Co. in the same general area follows a preferred stratigraphic horizon in schists. Uranium is, generally speaking, a very soluble and ubiquitous element. It occurs in at least two valency states and for this reason is not easily tied down in natural solutions. As Gruner' has pointed out, it is probable that uranium starts in the hexava-lent state in nearly all solutions instrumental in its transfer. It is believed that under oxidizing conditions the uranium moves in solution as the uranyl ion, UO. In solutions ranging in pH from 1 to 5, the uranyl ion is most commonly in association with

Jan 1, 1955

R. Culver, Colorado School of Mines I appreciated Professor Starfield's presentation, because his approach to blasting research reflects my feelings that a lot of practical work can be done toward making short-term advances that can be used by the blasting industry. We should not forget this in our attempt to obtain solutions to such idealized problems as a mathematical theory of cratering. The blasting industry would like very much to have the efficiency of the basic blasting processes improved from the range of 20 percent up into the range of 50 percent. And many of these problems should be approached and attacked in the laboratories. Blasting research at the Colorado School of Mines for the past two or three years has been aimed at improving the pre-splitting process, because we feel it will become increasingly important to the construction industry. We have attempted to develop a unified theory of how pre-splitting works; and the more we investigate, the more variables we find. We may never obtain an entirely satisfactory theory of pre-splitting, but we have developed a tentative explanation. One of our first conclusions was that we are making very poor use of the explosive in current pre-splitting practice. But to appreciate this we must first consider how pre-splitting works. A series of parallel boreholes are loaded with low density charges which are detonated simultaneously. (Delayed detonation has been tried, but most people agree that simultaneous detonation is best, and this is what we found.) Stress waves traveling out from each borehole interact with the stress waves from the two adjacent boreholes influencing the direction of the fractures that occur and propagate from each borehole. It has been suggested in private communication with Mr. Wilbur Duvall of the U. S. Bureau of Mines, that the fracture between the adjacent boreholes is a result of the net particle velocities above and below the pre-split plane which tend to set up a net tension along the pre-split plane. Regardless of what the exact mechanism is that causes the fracture to propagate from one borehole to the next, we know that it, in general, relies upon an interaction of the stress waves. However, if there is a large compressive stress normal to the pre-split place, it can practically eliminate any possibility of obtaining the desired pre-split by preventing the desired fractures from getting started. Aside from obtaining a fracture along the pre-split plane, the other major aim of pre-splitting is to minimize the fracturing that occurs around the borehole. We do this by drilling a large hole and putting a small charge in the middle of it. This results in a badly decoupled charge which is very inefficient; most of the energy is used in compressing the air in the borehole. Out of discussions about how pre-splitting works, we decided that perhaps there was some other explosive geometry which would make more efficient use of the explosive, and result in optimizing the pre-splitting process. Starting in the laboratory with small plexiglas blocks, we found that a fully-coupled explosive charge of 5 grains/in. of PETN gave random fractures extending about I in. from the borehole. A 1/4 in. plexiglas plug fit into a 1/4 in. hole in a similar block with the same fully coupled charge gave random fractures extending out only about 1/2 in. due to the energy absorbed in fracturing the plug. If the plug was split longitudinally but otherwise using the same geometry, it was possible to drive a fracture about 2 in. in either direction from the borehole, with an even smaller amount of fracturing around the borehole.

Jan 1, 1967

H. 0. Hofman, Boston, Mass. (communication to the Secretary*) :—The experimental demonstration by Professor H. Ries, of the fact that a mixture of clay and finely-ground flux will melt more readily than one in which the flux is less fine and therefore less intimately mixed, is very striking, and will be appreciated especially by those who have to discuss, before classes of students, fusions on a small or a large scale. The statement, that I " rather disputed" the influence of size of flux-particles on the ease with which fire-clay mixtures fused, is an erroneous inference from the paper written by Mr. B. Stoughton and myself in 1898.' We did not undertake to study the influence upon fusibility of the sizes of the particles, either of clay or flux. What we did try to find out was, whether the common practice of finely grinding raw or burnt clay, or a mixture of the two, before testing with Seger cones for resistance to heat and to fluxes, xould give the same results as if the materials were tested just as they were going to be

Jan 1, 1904

By C. B. Manula, R. L. Sanford, R. A. Rivell

This report describes the development and application of a rail haulage simulator that is readily adaptable for the analysis of a wide variety of operating problems. Various gaming, options have been integrated into the model structure which permit trial and error solutions from a computer terminal prior to capital committment in the actual operation. The high level of information retrieval available allows engineers and managers to develop production data which fit individual needs. In this report, emphasis was placed on the problem of organizing and performing the sequence of operations that are necessary to accomplish a complete mine materials handling simulation. Here, the Rail Haulage Sub-assembly was linked to the Production Sub-system to mine and move coal from seven operating sections to the intermediate and main-line track. The analysis was devoted to the problems associated with how the operating system performs and what alternatives were available to minimize idle times and hence increase productivity. In order to have some objective means of evaluating which of the alter- native methods for production was most appropriate, the choice was to replace the intermediate track with belt conveyors. Since the attempt here was to demonstrate model flexibility and not to establish the goals or trade-offs between computing objectives with which systems judgement must contend, no further alternatives were tried. This is left to management with the data and a problem to solve. Rail haulage simulation is not new, and several, operationally tested models are being used in practice (Bucklen, et. al., 1968).

Jan 1, 1974

By C. B. Alcock, R. A. Oriani

Some simple models of solutions are described; these include the regular solution, the subregular solution, and the quasichemical model. The assunzption underlying these models, the physical signzficance thereof, and the experimental manifestations are discussed. Examples are presented from the fields of liquid and solid metallic solutions, liquid slags, mattes, liquid and solid ionic solutions, and mixed carbides to show under what conditions and for which systems these solution models are fair descriptions. The deviations of real solutions from the models are of theoretical interest. Some such deviations, both for dilute and for concentrated solutions, arc pointed out and their Physical sigtzzficance discussed. DURING the past half century there has been a gradual accumulation of thermodynamic data for systems of interest to the metallurgist. There remain many gaps in the data, however, and the metallurgist must often face the problem of estimation of thermodynamic quantities where measured values do not exist. One might hope that the experimental progress would be matched by theoretical advances which would make such estimations possible with a high degree of confidence. However, theoretical progress has been disappointingly slow even for the simplest kinds of solutions, and since the multicomponent systems in which the metallurgist is interested are very complex, one cannot expect theory to be of much help to the metallurgist. In this situation, therefore, it seems worthwhile to examine some simple models of solutions from two points of view: firstly, to see if such crude models represent the thermodynamic facts in as many types of solutions as possible sufficiently well for the needs of the metallurgist, and secondly to see what the deviations from such models show to be important for consideration by theorists. BOND ENERGY MODELS OF SOLUTIONS The simple models that we will examine from these points of view may be termed statistical models, in that they are concerned with the thermodynamic consequences of some simple assumptions about the energy of an assembly of atoms, molecules, or ions, and do not inquire into the physical basis of the interaction. The underlying assumption of these models is that the energy of an assembly of molecules (by which we include also atoms or ions) is given by the sum over all interaction energies of molecules taken two at a time; we will discuss only those models in which the pairwise interactions are restricted to those between nearest neighbors. Thus, in a pure substance of bond energy EAA, the internal energy (with respect to some specific reference state) will be expressed as NAA EAA where NAA is the number of nearest-neighbor pairs. A solution of molecules A and B will be characterized by NAA EAA + NBB EBB + NAB EAB where the Eij represent the bond energies of the nearest-neighbor i-j pairs. If one assumes that the EAA and EBB are the same in the pure components as in the solution, and that the coordination numbers in the two pure substances and in the solution are the same, then the energy of the solution with respect to the pure components (i.e., the energy of solution) is a function of the following linear combination of the bond energies: EAB - 1/2(EAA +EBB) = w. The thermodynamically ideal solution is defined as one in which the activity of each component is equal to the mole fraction of that component at all concentrations and all temperatures. It follows that

Jan 1, 1962

By AIME

AS with Phil Kraft, referred to on this page last month, travel has always held a great fascination for Raymond Frank Baker and for that reason he determined to become a geologist. He had heard that geologists travel and that was what he wanted to do. Now as chief geologist for The Texas Co. his early wish has been fulfilled-he spends almost one third of his time journeying' from one oil field to another. Mr. Baker was born in New Haven, Conn., on Jan. 11, 1892, and went through the public schools in New Britain. A stalwart New Englander, he attended Yale and in 1912 received a degree in civil engineering. For a year following this he worked as a civil engineer for the New York Central Railroad, but his early urge to travel widely could not be satisfied here. So in 1913 he re-entered Yale and until 1916 studied mining and economic geology. He had a little taste of field work, which later became so enjoyable to him, in the summer of 1915 when he worked with the U. S. Geological Survey as a geologic aid. In 1916 he made his first contact with The Texas Co. when he entered their Tulsa office as a geologist. This early career was interrupted by service in the

Jan 1, 1947

By S Dunbar, S Harrison, J Cilliers

‘Those who cannot remember the past are condemned to repeat it.’George Santayana (16 December 1863 in Madrid, Spain to 26 September 1952 in Rome, Italy). Philosopher, essayist, poet and novelist.The minerals industry requires specific technical expertise in mining and mineral process engineering, geoscience, environmental science and social sciences to maintain and operate its current business and to develop future projects. A steady supply of new graduates is essential to replace not only retirees, but also those who left the industry during the recent downturn. The supply of trained graduates is however not instantaneous, and there is a four-year lag from entry into university to graduation. It is essential that this lag in human resource supply and a likely shortage of knowledgeable, qualified talent is taken into account when considering risks to the business of mining. The shortage of skilled professionals has in the past resulted in unsustainable salary expectations and is likely to pose financial and execution risk to new projects. This paper will review some recent statistics of students in training from around the world and explore what action is required to not only sustain the training courses that provide future ready talent to the mining industry, but also ensure that graduates from these courses are equipped to create change and be leaders in the industry. The future prosperity of the industry is dependent on delivering sustainable stakeholder returns through the cycle. This will be achieved by developing capable individuals that can respond to the complex, adaptive challenges facing the industry.*This is an abstract only. No full paper was prepared for this abstract.*CITATION:Plint, N, Cilliers, J, Dunbar, S and Harrison, S, 2018. Back to basics: resourcing the mining industry, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 33–34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

This presentation addresses the sources and weighting of project risk in coarse gold deposits with relevance to experiences at the Ballarat mine and Castlemaine goldfield. With sample representation and reliability often a source of great error in the resource estimation of coarse gold deposits, it follows that this matter should be of greatest risk to a mining project - but is it? What are the costs and efforts required to best quantify the sampling error due to nuggetty effect? After all, the main problem in Victorian gold mining ventures in the current decade is not the amount of gold available, but defi ning which portion of it can be converted to Ore Reserves or more so profitable gold bars. The author postulates that greater risk to the project lies in the geological interpretation and matching resource spatial parameters to mining methods, than the degree of uncertainty related to grade due to nuggetty gold. Recent experience in the Victorian goldfi elds is that the investor market has already severely discounted Mineral Resources reported in accordance with The JORC Code - so if they don't believe in the capacity to upgrade the resource why should we? To this end, Castlemaine Goldfi elds Ltd at its Ballarat gold project does not intend to estimate its gold mineralisation for public release, instead choosing to focus on the geological interpretation and mine planning elements. So with coarse gold deposits, is your Mineral Resource reported with The JORC Code a glass half full or half empty? Our mining forefathers in Victoria had no predictive tools which could define resources to any degree and yet were successful. By over emphasis on the definition of mineral resources and particularly the sampling error, are we ignoring the basics of cost control, solid geological interpretations and maximum mining flexibility. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Aug 1, 2010

WELL known member of the Institute, Henry Krumb, survived the Japanese earthquake and has written a most interesting description of his personal experience to a friend in New York, an extended excerpt from which we publish, by permission, below. Not having been written for publication it has increased value as a human document in its vivid description of personal impressions and sensations in the midst of such a catastrophe. The earthquake was the most terrible experience I have ever passed through. We arrived at Miyanoshita, Friday, Aug. 31, about 6 p.m., having left Yokohama about 2:30 that afternoon by automobile. It was a most beautiful ride, although rather warm, but not unusually so, as it has been uncomfortably hot ever since we arrived in Japan. The first part of this automobile trip was along the old highway from Kyoto to Tokyo, which is lined with fine old pine trees. There are 52 villages along this highway and we saw real Japanese country life: naked children, both boys and girls, and men wearing nothing but gee-strings. The country on either side was intensively cultivated, the green rice fields and lotus ponds making a most beautiful sight. The occasional hills were all re-forested with young pines. In places the road runs close to the ocean beaches. The last part of the trip was up a steep mountain road, cut out of the side of the mountain. On one side of the road, in the gulch below, was a roaring river. The road crosses this river several times. Miyanoshita is beautifully located on the side of a mountain about 400 ft. above this river at an altitude of 1400 ft. The grounds of the hotel are laid out in Japanese style, small lakes with fish, waterfalls and dwarf trees making a very pretty sight. On the morning of Sept. 1, after walking around the garden and the hotel, we went to our room and I started to write up a few notes. Mrs. Krumb was reading a guide book. A few minutes before noon she came over to the table where I was writing and said that it was about lunch time. Just at that moment hell broke loose. It was the first earthquake I have ever experienced and I did not immediately realize what was happening. The building was shaking as a mine office might shake when heavy blasting was going on near by. Mrs. Krumb, having experienced many earthquakes, stepped to the open door between our room and the bathroom and called to me to get out from under the chande-lier. The plaster was commencing to fall and a large wardrobe fell over. I then knew what was happening and ran to the win dow. Before I reached it a large chunk of plaster from the ceiling hit me on the head and cut my forehead and nose. Mrs. Krumb ran for the other window just as the marble mantelpiece and the dresser fell. Without any hesitation, she jumped out of the win-dow and I followed suit out of the other. Luckily neither of us sprained an ankle-we had jumped 8 ft. We started to runaway from the building but had not gone more than 25 ft. when a second shock or rather a continuation of the first became so violent and the ground under our feet was trembling so that it was almost impossible to stand up without holding on to a tree. The ground seemed to have become liquid and rocked violently, it seemed to me in a vertical direction. In some later shocks the movement was more horizontal. About this time Mrs. Krumb saw the blood on my face and commenced to break down, but only for a moment: As soon as she saw it was not serious she was all right and during the following days stood the experiences and hardships as well as the best of them:

Jan 11, 1923