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By Louis W. Towle

A brief history of the use of Ammonium Nitrate in explosives and blasting agents is given. Methods of manufacture and physical properties of the various types of Ammonium Nitrate are given with particular reference to their use in blasting agents Important properties of blasting agents discussed are sensitiveness, methods of initiation, velocities of detonation, strength, density, products of detonation, rate of pressure development, and borehole pressure.

Jan 1, 1959

By H. C. Cooke

Geological examination of the underground workings of the Horne and Aldermac mines during the summer of 1927 has brought out the following facts: (1) That the ores tend to replace bodies of breccia or tuff rather than massive lava or dyke material; (2) That the faulting and folding at the Horne has had a pronounced effect in localizing the ore-bodies; (3) That there is a tendency in cert?-in cases for ore-bodies to be localized beneath gently dipping dykes, which acted as impervious roofs; (4) That there is a great difference in age between the chalcopyrite part of the ore-bodies and the pyrite-pyrrhotite portion. A statement of the development to date at the Aldermac mine is also included in the paper. ALDERMAC MINE The Aldermac property is made up of eight claims in the western half of Boischatel township, Quebec, including 747 acres in all. The mine itself is approximately three miles, 25 chains from the west boundary, and four miles, 55 chains from the north boundary, of the township.

Jan 1, 1928

By Alan Bauer, Melvin A. Cook

Measured detonation pressures of "prills and oil" (94/6 ammonium nitrate/fuel oil) and three of the new "slurry" blasting agents are presented and compared with computed, ideal detonation pressures and with detonation pressures expected from the measured detonation velocities. Results seem to show that the peak pressure in the detonation wave in these cases is the Chapman-Jouguet pressure and that no "spike" exists in these detonation waves. The absence of the Zeldovich-von Neumann "spike" is noteworthy in view of the very long reaction zone lengths of these mixtures. The measured detonation pressure of one of the slurry blasting agents (DBA-3") under steel confinement ( 172 kilobars) is shown to be considerably greater than the ideal detonation pressure of 75 per cent gelatin dynamite (p. = 135 kilobars) despite the fact that the detonation was still somewhat non-ideal in "DBA-3," its computed ideal detonation pressure being 180 kb. The popular 94/b AN /FO blasting agent exhibited a detonation pressure of only 13.5 kb in 5" paper tubes, but 37.5 kb in 5"• steel pipe compared with a computed ideal pressure of 40 kb.

Jan 1, 1961

By Frank B. Fulkerson

Three of the five primary aluminum producers in the Pacific Northwest have facilities in the region to make aluminum mill products. Only one of the three, however, produces a variety of shapes and forms. The principal reason for the lag in development of an aluminum mill products industry was found to be transportation cost. The long range outlook is for expansion, based mainly on growth of the western market for aluminum used in construction, containers and packaging, electrical applications, diesel trucks, mobile homes, and irregation pipe. Consumption of western aluminum mill products in 1985 is projected at 1.1 million tons, compared with estimated consumption of 250,000 tons in 1961.

Jan 1, 1965

By W. E. Pittman

The Bureau of Mines, as part of its Health and Safety Technology Program, is conducting research on the use of ground penetrating radar (GPR) for mine hazard detection. GPR offers a possibility of mapping immediate below-surface geologic conditions, including faulting and other anomalies, thereby exposing potential safety hazards to miners. This report summarizes a literature review of the current status of GPR research in and outside the Bureau.

Jan 1, 1984

By Frank B. Fulkerson

Three of the five primary aluminum producers in the Pacific Northwest have facilities in the region to make aluminum mill products. Only one of the three, however, produces a variety of shapes and forms. The principal reason for the lag in development of an aluminum mill products industry was found to be transportation cost. The long range outlook is for expansion, based mainly on growth of the western market for aluminum used in construction, containers and packaging, electrical applications, diesel trucks, mobile homes, and irregation pipe. Consumption of western aluminum mill products in 1985 is projected at 1.1 million tons, compared with estimated consumption of 250,000 tons in 1961.

Jan 1, 1965

By A. Adeli, A. V. Metcalfe, E. Addo, E. Sepulveda

"The accurate modelling of geometallurgical data can significantly improve decision-making and help optimize mining operations. This case study compares models for predicting copper recovery from three indirect test measurements that are typically available, to avoid the cost of direct measurement of recovery. Geometallurgical data from 930 drill core samples, with an average length of 19 m, from an orebody in South America have been analysed. The data includes copper recovery and the results of three other tests: Bond mill index test; resistance to abrasion and breakage index; and semi-autogenous grinding power index test. A genetic algorithm is used to impute missing data at some locations so as to make use of all 930 samples. The distribution of the variables is modelled with D-vine copula and predictions of copper recovery are compared with those from regressions fitted by ordinary least squares and generalized least squares. The D-vine copula model had the least mean absolute error. IntroductionIn this paper we compare the use of D-vine copula, generalized least squares (GLS), and ordinary least squares (OLS) for modelling geometallurgical data from an orebody in South America. The first objective is to construct models for predicting copper recovery (Rec) from the Bond mill index test (BWi); resistance to abrasion and breakage index (A*b); and semi-autogenous grinding (SAG) power index test (Spi). This involves fitting a D-vine copula and regression models fitted by OLS and GLS. The second objective is to investigate the performance of the fitted models for predicting Rec (Willmott and Matsuura 2005).Traditional resource model approaches either ignore the mineral processing characteristics of extracted tonnages or treat processing as an independent component of a mining operation. The net present value (or any other objective) can be truly optimized only by considering the mining operation as an integrated system in which net value is defined as the end-product that the company sells. This approach requires the resource model to be extended to include all relevant rock properties and processing responses."

Mar 1, 2019

By Rene Padilla, Siyanda B. Mngadi, Gerrie van Aswegen, Peter Stonestreet

While many mine tunnels are developed through ground that must be riddled with the sources of small (and larger) mining induced seismic events, recorded by the mine seismic monitoring systems, we do not see planar discontinuities classified as seismic sources in the geotechnical databases. Here we list criteria that may be useful to identify discontinuities in drill core which are dynamic slip surfaces, parts of mining induced seismic sources. Such shear rupture surfaces in core would generally be powdery, cohesionless, and rough on cm scale. Finely broken rock and rock flour may be found in the core boxes at the discontinuities. Slickensides would be soft (easily destroyed) and kinematically consistent with the local stress field. In some cases, a cross fabric would be present, orthogonal to the slickensides, being the intersections of en-echelon extension fractures, within the dynamic shear zones, with the shear zone walls.

Apr 26, 2022

By John H. Soulé

"Bureau of Mines engineers3/ examined the White Eagle fluorspar mine on September 3, 1943, and again on February 17, 1944. The examinations led to a proposal for the exploratory project upon which this report is based. The project, which was supervised by the author and P. L. Russell, was started on April 6, 1945, and completed on June 26, 1945.Geologists4/ of the Federal Geological Survey examined, mapped, and reported on this property prior to initiation of the Bureau of Mines project.In its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. H. S. Dean, assistant director.Special acknowledgment is due to C. H. Johnson, Rolla, Mo., Division, Mining Branch; to W. R. Storms, mining engineer in charge of the New Mexico field office; and to J. H. Hedges, chief of the Tucson, Ariz., Division Mining Branch. Acknowledgment is owed, also, to Robert Trace and Howard Rothrock, of the Federal Geological Survey, for help in mapping the surface and in logging drill cores.The White Eagle claim is in the east-central part of sec. 34, T. 19 S., R. 9 W., Cooks Peak Mining District, southeastern Grant County, New Mexico. The property is reached from Deming, N. Mex. by taking the paved U. S. Highway No. 260 northwestward for 13 miles to the junction with State Route 61. State Route 61 is a graded but unpaved road and is followed northward for 8 miles to a junction with a poor dirt road, which is followed eastward for 11 miles to the mine. Silver City, N. Hex., is about 50 miles northwest of the mine and may be reached by several routes.The White Eagle patented claim was owned by L. H. Duriez of Vanadium, N. Mex., W. D. and W. A. Howard of Deming, N. Mex., Alvan N. White of Silver City, N. hex, and: Mrs. E. M. Saunders of Los Angeles, Calif. D. P. McCabe of Lordsburg, N. Mex., a former lessee, has recently contracted to purchase the property.The White Eagle claim was located about 1920 and was patented in November 1933. It was leased to Cooper Shapley of Deming, N. Mex., in July 1933; to General Chemical Co. from August 1938 to May 1940; to Antonio Cristo from October 1940 to the fall of 1942; and f is ally it passed into the hands of D. F. McCabe of Lordsburg, N. Mex., in May 1945.Approximately 25,000 tons of fluorite ere containing about 65 percent CaF2, have been mined and shipped from this property.5/ Most of this ore was mined by Cooper Shapley and the General Chemical Co. and shipped to the General Chemical Co.'s La Purisima mill at Deming. No exact data on production are available."

Jul 1, 1946

By Alfred H. Brooks

The developments of the past five years have shown that Alaska, as a field for mining, stands in the first rank among the possessions of the United States. Its annual gold output is now about $8,000,000. It produces silver, copper and coal in commercial quantities and its recently discovered tin and petroleum promise to become important products. Concurrent with the gradual development of this wealth, the mining public has ceased to regard the territory simply as an arctic province where a few placer-miners struggle with adverse conditions to secure a grub-stake or a modest fortune. Of late years there has been a large influx of capital to investigate its mineral resources, but in its area of nearly 600,000 sq. miles there still remain large, unexploited and little-known fields. This work of investigation has been carried on under adverse conditions, and reflects credit on all who have shared in it, whether prospectors, mining engineers, or geologists. It is the purpose of this paper to outline briefly what has been, and is being, accomplished toward furthering the knowledge of Alaska's mineral wealth, and in this connection to present a brief history of the operations of the United States Geological Survey in the territory. A list of the publications of the Geological Survey, which pertain to Alaska, is presented as an appendix, in the hope that it may prove useful to those who are interested in the mining of this northern province. During the Russian occupation of Alaska, from 1783 to 1866, but little attempt was made to delineate its geographic features or to study its geology and mineral resources. The Russian-American Co., which long held control of the territory, was entirely absorbed in the exploitation of its fur trade,

Jan 1, 1905

By D. R. Cook, W. M. Shepard, H. T. Morris

The East Tintic district in central Utah has produced ores of gold, silver, copper, lead, and zinc valued at more than $120,000,000. All of this ore has been produced from blind ore bodies in Paleozoic sedimentary rocks that are concealed beneath hydrothermally altered volcanic rocks and cut by intrusive bodies of Eocene age. The Paleozoic rocks, which range in age from Early Cambrian to Mississippian form the core and limbs of a large, northtrending asymmetric anticline that is cut by low-angle thrust faults, high-angle transcurrent faults, mineralized fissures and faults, and normal faults that are both older and younger than the mineralized fissures. The ore bodies generally may be grouped into two classes: ( 1) massive replacement bodies that are rich in silver, lead, zinc and manganese and (2) fissure veins that are valuable primarily for their content of gold, copper, and silver. The replacement ore bodies are localized chiefly in the Middle Limestone Member of the Ophir Formation of Middle Cambrian age where it has been thrust-faulted against older or younger rocks and cut by northeast-trending mineralized fissure zones. The fissure veins primarily are productive only in the Lower Cambrian Tintic Quartzite. Extensive lowgrade deposits of lead-zinc-silver ore recently have been discovered in Devonian carbonate rocks in the Lower plate of the East Tintic thrust fault but as yet are unevaluated. The principal guides to ore include: ( 1) intersections of northeast-trending fissures and crossbreaking faults that brecciate the carbonate rocks; (2) zones of late-stage pyritic, calcitic, and sericitic alteration in the lavas; ( 3) primary geochemical anomalies in the altered rocks; and ( 4) mineral zoning patterns of the known ore bodies. The present development of the Burgin mine would seem to assure the continued productivity of the district for at least a decade.

Jan 1, 1968

By J. P. Sieverson

The Comprehensive Environmental Response, compensation, and Liability Act (CERCLA -commonly referred to as Superfund) was passed into law in December 1980 in the wake of such incidents as Love Canal and the Valley of the Drums. Superfund was originally perceived as a way of cleaning up spills of hazardous substances and/or cleaning up abandoned hazardous waste dumpsites. In February 1981, Michael Cook, EPA deputy assistant administrator for hazardous emergency response, called Superfund "a tremendously powerful law. It could revolutionize the way the environment is protected, but we certainly don't intend to realize the full potential of the law for some time." These words have proven prophetic for Asarco's East Helena Smelter.

Jan 1, 1988

By James E. Adler, Timothy C. Richmond

The Stillwater District is located in south central Montana approximately 75 miles southwest of Billings, the state's largest city. It lies along the northeast front of the Beartooth Mountains and is within the boundaries of the Custer and Galatin National Forests. The first white visitors in the district were the early trappers, who were soon followed by the prospectors. These early prospectors were drawn to the area by gold and silver discoveries at Cooke City in 1870 as well as by the large gossan formation in Verdigris Creek near the west bank of the Stillwater River and by several scattered smaller gossan exposures throughout the area. The first patented mining claims were recorded in September, 1886.

Jan 3, 1974

By Oliver C. Ralston

DURING the development of froth flotation for the treatment of sulphide ores, a certain amount of information was collected about a few of the nonmetallic minerals, and occasionally the gangue minerals in the sulphide ores showed an embarrassing tendency to float. However, for many years efforts were expended to develop reagents that would cause wetting and depression of these minerals. Among the nonmetallics, the minerals sulphur, graphite, and talc probably should be classified as 'natural floaters', and perhaps sericite. They respond to almost any type of flotation reagent, and their beneficiation by flotation had been attempted years ago. Flotation of sulphur is now common practice, and graphite was concentrated during the World War in many mills, most of which have now closed down. A talc mill has just been constructed, and another may soon be erected. Second to the 'natural floaters' come the 'easy floaters', cassiterite, fluorite, barite, mica, colloidal gangue, and paper pulp from white water of paper mills. That these materials responded to some of the early flotation reagents, as oleic acid, has long been known; occasional references to their behaviour are found in the very early flotation literature and in that of today. In general, however, nonmetallic minerals, valued at $2.00 to $15.00 per ton, have for a long time been regarded as cheap products and not worth much beneficiation. Consequently, only high-grade natural deposits suitable for direct mining and sale have been gouged out. Furthermore, the mining of these minerals has too frequently been in the hands of 'super-practical' men-men of no technical or other training, willing to work for a very low compensation. From the social standpoint, nonmetallics has been the field for small, untrained enterprisers with little money to spend on plant or equipment. But times have been changing. The impact of technically trained men on the old industry has revealed appalling losses and inefficien-cies and proved the value of processing materials discarded or avoided by the old regime.

Jan 1, 1937

By S Van Duin, I Porter

This paper discusses how advanced manufacturing technology (AMT), which is fundamentally reliant on and developed via multi-disciplinary skills, has benefitted non-mining industries, and what lessons can be derived from this experience to benefit the mining industry, particularly underground coal mining. Examples of AMT use in æconventionalÆ industry, some drawn from the more than 25 years experience in many different industries of the Automation and Robotics team at the University of Wollongong, are described to show typical benefits, risks and opportunities expected in using AMT. Applying AMT to mining brings many unique challenges and this paper expands on these and then provides practical examples of how a multi-disciplinary team can develop new processes and systems leading to productivity, safety and other benefits for underground coal mining.

Sep 26, 2011

By A. M. Beebee

IN the present century the coal and manufactured gas industries have been eclipsed in public interest by oil, natural gas, and hydro- electric energy, which have had the benefit of rapid development and novelty. I sometimes wish that our social- order were such that hydro power had been developed first, that the use of gas from coal had never been seriously considered, and that our domestic energy requirements were supplied by other fuels. Sup- pose the manufacture of gas from coal should then come on the scene at the present time with the current plight of the railroads, coal regions, and labor generally, presenting the fact that it could increase the amount of coal mined and shipped by the railroads by some 16,000,000 tons, and increase the coal used at existing u plants five times. Imagine the great public interest that would be manifested; it would supply the cooking and water-heating requirements of a community with a superior character of service at a cost to the customer approximately half that which had obtained previously. Would not such a situation be heralded as the salvation of our country and all help be given it?

Jan 1, 1940

By Theodore Simons

I. INTRODUCTION PERMISSION to present this paper at the February, 1915, meeting of the Montana Section of the American Institute of Mining Engineers was liberally granted by W. A. Clark, Jr., President and General Manager of the Timber Butte Milling Co., and by the representative of the Minerals Separation Co. For the many courtesies shown the writer on his visits to the mill and for information supplied, he is indebted to all the officers of these companies, especially to W. N. Rossberg, W. D. Mangam, Hamilton Cooke, Jr., T. M. Owen, T. C. Wilson, R. McGillivary, L. L. Quigley, C. Bartzen and others. The writer takes this opportunity to herewith express to them his appreciation and sincere thanks.

Jan 6, 1915

By L. G. Closs

Gold continued to be the primary focus of minerals exploration worldwide during 1995. Other targets, though, included primary diamonds and base metals, especially copper deposits amenable to solvent-extraction/electrowinning (SX/EW) processing. The discovery of nickel, copper and cobalt at Voisey Bay in Labrador, Canada was an unusual surprise. Meanwhile, exploration geochemistry continues to evolve to meet new challenges. The major event in this category during 1995 was the17th International Geochemical Exploration Symposium (IGES) held in Townsville, Queensland, Australia in May. The meeting was sponsored by the Association of Exploration Geochemists, which celebrated its 25thanniversary of service to the mineral industry, and the Economic Geology Research Unit of James Cook University, Townsville.

Jan 1, 1996

By R Grobler, D Burger, L Alberts

The current climate in the mining industry is allowing mining companies to further broaden their views and investigate technologies to improve the safety, efficiency and cost-effectiveness of their operations. Furthermore, underground mine environments will become more demanding for mining equipment and personnel as orebodies become deeper in weaker ground conditions with more extreme environmental conditions. Loading and hauling can represent significant components of the production cycle of an underground mine and automation of these activities can offer considerable benefits. Sandvik has accumulated a long history and experience in loading and hauling automation in underground mining. Since the late 1980s Sandvik has actively participated in several major research and development automation programs leading to the commencement of the development of an integrated system for semiautomated loading in 1999. Development work was later conducted to expand the capabilities of the system for automated hauling during 2001 and the AutoMine« system became commercially available. The first delivery of the AutoMine« system was completed in August 2004 in South America, where the system continues to operate in a full-scale production environment and is being expanded as the production area enlarges. Further systems have been delivered and are operational in North America, Africa and Europe. This paper focuses on the AutoMine« system deployed in Block 4 at De Beers Finsch Mine in South Africa. An overview of the mine and the process used to acquire the system and the key drivers which led to the selection of an automated solution are described. An overview of the initial system installation, subsequent expansions and future plans are presented. This is followed by a summary of the implementation and operational experiences associated with automated underground operations. The paper concludes by summarising the benefits that have been realised.

Jan 1, 2008

By M. Zanini, D. Wong

ABSTRACT: Metals market improvements in 2005 drove the desire to increase nickel throughput and the production of nickel oxide sinter at the Vale Ltd. Copper Cliff smelter. Significant difficulties were encountered due to the unreliable quality of Bessemer matte being produced. Concentrate feed changes and the loss of technical and operational expertise during the previous market downturn contributed to the challenge of making the required improvements. Significant progress has been made in the converter aisle by focusing on employee engagement and standardizing best operating practices for a new generation of skimmers. This paper documents these initiatives and seeks to balance the art and science of converting.

Jan 1, 2012