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By J. Douglas Causey

The Bureau of Mines conducted mineral investigations of the Peace Rock and Deadwood River roadless areas in Idaho, in 1992. Literature research was done by the Idaho Geological Survey. The study areas contain black sand placers (thorium, columbium, tantalum, titanium, uranium, and rare earth elements), gold, and molybdenum prospects. Except for unrecorded placer gold, there has been no mineral production from the areas. No mineral resources were delineated, but a multi-million tonne molybdenum resource is in the Big Pine Creek area and a 142 million m' black sand deposit is in the Stolle Meadows, Peace Valley, and Deadwood River areas. The Deadwood mine produced zinc, lead, and silver. There are six mining districts in and adjoining the areas; Warm Lake, Deadwood, Garden Valley/Lowman, Banner, Summit Flat, and Grimes Pass. Few claims, mostly placer, were active in the study area in 1992. The study areas are underlain by granitic rocks of the Idaho batholith. Most of the deposits are alluvial accumulations of heavy minerals weathered out of the Idaho batholith. Stockwork and narrow veins along shears account for the base and precious metal concentrations. Eleven prospects were examined. Workings consist of drill holes, pits and adits. Geothermal resources (hot springs) occur mainly along the Middle Fork Payette River; Vulcan Hot Springs is a designated Known Geothermal Resource Area. Sand and gravel resources are of local interest.

Jan 1, 1993

By James F. O'Neill

Brown iron ore resources in Barbour , Butler , Crenshaw , and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama . The aggregate footage drilled was 18,010 linear feet . When developed , reserves of 12,664,000 long tons of crude ore were indicated , containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet . Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons . Beneficiation of samples by simulated log washing and use of a 1 / 8 - inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese . Screen- test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200 - mesh screen . Clay was prominent in micron - size slimes . Silica was deleterious in the minus 20 - mesh size . While an indicated 2,198,000 dry long tons of usable iron ore can be recovered , sink - and - float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing . However , applicable commercial processes have not been demonstrated .

Jan 1, 1965

By Michael Sokaski

A dense-medium cyclone pilot plant was built to clean 112-inch to 0 size coal. This pilot plant does not require the removal of the extremely fine material (usually minus 1/2-mm) from the feed, which is necessary in conventional dense-medium cyclone plants. The essential difference between conventional cyclone plants and the pilot plant is in the medium-recovery system. The latter uses a combination of sieve bend screens, classifying cones, and magnetic separators for medium recovery. Eight tests were run in the pilot plant at a feed rate of 5 tons per hour with four different raw coals and one crushed jig middling product. Sharp separations were obtained as indicated by an average error area of 27 and probable error of 0.047 for the 112-inch to 200-mesh size range. Magnetite loss averaged about 2.5 pounds per ton of feed. The influence of several factors on cleaning performance of the cyclone was investigated. The diameters of both the overflow and underflow orifices were found to be important for optimum cleaning performance, but these diameters could vary over a wide range without serious effect; however, if this range was exceeded, cleaning performance deteriorated. Better cleaning performance was obtained when the cyclone inlet pressure was increased from 9 psig to 13 psig. The size of the magnetite particles in the medium was found to have a substantial effect, and the best cleaning results were obtained with grade B magnetite. Demagnetizing the magnetite in an effort to decrease the effective particle size did not improve cyclone performance.

Jan 1, 1963

By Harry E. Brownlow

The United States Bureau of Mines contracted Norecol to prepare a report identifying the regulatory processes associated with metal mine development in British Columbia using the Snip Mine as a case study. The intent of this study is to assist industry and regulatory agencies in developing understanding as to differences in objectives, perspectives and operating methods. The case study will be incorporated into a larger report summarizing the comparative advantages and disadvantages of metal mine permitting in British Columbia and Alaska. The purpose of the report is to identify the development schedule and permitting process at Snip which will assist the U.S. Bureau of Mines in suggesting improvements in environmental review and permitting processes for mine developments. The report provides an abstract of the environmental assessment review processes in Canada and the Mine Development Review Process in British Columbia and provides an understanding of the linkages between policy, legislation, and environmental review.

Jan 1, 1992

By P. L. Swanson

Over a recent 20-month observation period, the U.S. Bureau of Mines obtained seismogram records from a single vertical-component, short-period seismometer installed at the surface of a metal mine in northern Idaho. The seismic events were analyzed for local (Richter) magnitude (M), time of occurrence, location, and relation to rock bursting and production blasting. Approximately 150 seismic events with -0.5 = M = 2.9 were located within the mine, yielding a b value (slope of the logarithm of the number of events with magnitude greater than M versus M) of 0.5. Event locations were constrained using a dense underground array of high-frequency accelerometers. Twenty of the surface-recorded events, with 0.5 = M = 2.9, were associated with rock bursts that produced damage requiring at least 1/2 day of cleanup and/or repair. Other possibly hazardous rock bursts, with magnitudes as small as -1.1, were numerous but were not associated with significant structural damage. Approximately 60 pct of the seismic events with M > -0.5 and 75 pct of damaging rock bursts occurred within 45 min of blasting. Estimates of characteristic rupture dimensions for rock bursts with -1.1 = M = 2.9, based on a conventional dislocation shear-slip model of failure, range from 3 to 300 m.

Jan 1, 2010

By Xavier B. Starnes

"INTRODUCTION The Krausse Estate property was the site of the first lead silver mining in western Kentucky, which began with the sinking of the Andrew Jackson shaft in 1835 3/. The earliest miners considered fluorspar of no value and threw it upon the waste dump, but Crittenden County later became an important part of the western Kentucky and southern Illinois fluorspar district 4/, which has produced about 90 percent of the fluorspar mined in the United States. By 1945, approximately 35,000 tons of fluordpar ore had been produced from the Estate property.This property can be reached by traveling west from Marion on Highway 60 from 2.5 miles, than northward 3 miles. The road from the paved highway to the mines is very rough but not impassable even in bad weather. Ore is hauled 5 1/2 miles by truck to custom mills at Marion, a town of 2, 000 population, where the Illinois Central Railway was a freight station.Hurricane Creek runs through the eastern part of the property. The surface slopes steeply upward to west from the creek, and the topography is rough. The top of the hill is about 150 feet above the creek.The climate permits working throughout the year, but spring rains cause surface water to enter mine and water apparently drains southward along the fractured fault zones, so that when no water is being pumped at properties north of the Krausse Estate a heavy flow comes on the Krausse."

Sep 1, 1946

By Michael Hamilton

Mineral resources have been identified at two properties in the Ten takes RARE II area (table 1). Commodities consist of copper and silver. The deposits, in the northwest part of the study area, are hydrothermal and associated with fissure veins that developed along northwest-striking faults within the Precambrian Purcell Lava. In addition to the identified resources, there is high potential for additional copper-silver resources at these properties and moderate potential for copper-silver-lead-zinc-bariun resources at five others (table 2) in the portion of the study area that is underlain by the Purcell. There is no evidence that significant mineralization occurred in strata above or below the Purcell.

Jan 1, 1983

By L. W. Kelly

The purpose of this paper is to indicate some of the benefits that have been derived in the Zeigler No. 3 mine by using roof bolts under extremely adverse roof conditions J with the thought that much better results could be obtained in other mines with more normal roof conditions by applying some of the practices that were developed in this mine. Some of the benefits that have been obtained in this mine, which will be shown in this paper, are: 1. Increased tonnage per man-shift at the face when roof bolts are used, as compared to the tonnage under similar conditions when conventional timbering methods were used. 2. Increased efficiency of roof bolting by giving the foremen a definite plan to follow. 3. Reduction in delays caused by failures of the trailing cables of loading, mining, and drilling machines. 4. Reduction in the number of accidents after roof bolting was adopted. Inasmuch as the success that followed roof bolting in this mine was obtained under one of the most treacherous roofs in the Middle West, it is reasonable to suppose that correspondingly better results could be obtained under more favorable roof conditions by using the same procedure.

Jan 1, 1952

By E. J. Lintner

This paper is one of a series being prepared by the Bureau of Mines describing; gypsum mining and crushing methods and costs at various operations throughout the, United States. These papers are designed to dissemminate technical information regarding methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs may in many instances cause embarrassment to the individual operator as well as to the industry as a whole; on the other hand, operating costs are essential to the technical discussion and. study of the methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulation shall ensue. The following report deals specifically with the mining and primary crushing methods employed at the plant of the Ebsary Gypsum Co., Inc., Wheatland, Monroe County, N. Y. This company is capable of maintaining a maximum yearly production of 220,000 tons of crushed gypsum, thereby ranking as one of the largest gypsum operators of the State. The methods and practices employed typify the standard methods followed by gypsum producers in western Now York State, The bed of gypsum mined lies only 35 feet beneath the surface and is above average thickness for this vicinity.

Jan 1, 1937

By Lucia Kuizon

The Antimony RARE II area is underlain principally by Mesozoic igneous rocks associated with the Sierra Nevada batholith. The San Andreas fault zone is near the southern boundary. Metallic mineral deposits are associated with the fault zone. These deposits were formed from magmatic solutions, and tend to be along shears and fractures within the country rock. Marble and dolomitic marble deposits occur in Paleozoic roof pendants or inclusions in the Mesozoic intrusive rocks in the area (Troxel and Morton, 1962, p. 52).

Jan 1, 1982

By P. D. Lindahl

[A cost/benefit analysis was conducted by comparing the industry cost to protective structures on low-coal face equipment with the benefits paid for injuries/fatalities considered preventable by the use of these structures. Th industry costs were based on estimates by OEM's and rebuild shops for install protective structures on new and rebuilt face equipment. The accident benefit was based on evaluations performed by the USBM Accident Cost Indicator Model. Industry wide population data were developed on low-coal face equipment and injuries/ fatalities preventable with protective structures. The results of the analysis are to be used as a tool by USBM in determining the feasibility of continuing development of cab and canopy technology for low-coal equipment.]

Jan 1, 1983

By P. L. Sibrell

The U.S. Bureau of Mines has tested cyanide leaching for recovery of palladium (Pd) from spent petroleum processing catalysts. Three different catalyst samples were supplied by a spent-catalyst processor. These catalysts consisted of a zeolite base and contained 0.4 to 0.7 pct Pd. During alkaline cyanide leaching, the catalysts exhibited ion-exchange properties due to their zeolite matrices. Hydrogen ions were released from the zeolite in exchange for sodium ions in solution, resulting in a significant decrease in solution pH. This could present a safety hazard because of the potential for release of toxic hydrogen cyanide gas. A pretreatment step where the catalysts were contacted with a 1.0M sodium hydroxide solution was found to prevent the pH shift from occurring. Following the sodium hydroxide pretreatment, two stages of leaching at 160 °C with solution containing 1 pct sodium cyanide and 0.1[M] sodium hydroxide gave at least 75 and up to 95 pct Pd recovery. The Pd was quantitatively recovered from the leach solution by thermal decomposition in an autoclave at 250°C for 1 h. The Pd content of the precipitate was over 50 pct. Thermal decomposition also decreased the total cyanide content of the barren solution to less than 0.2 mg/L. The catalyst leach residues passed the Federal Toxicity Characteristic Leaching Procedure and the California Waste Extraction Test, indicating that landfill disposal of the leach residues would be acceptable.

Jan 1, 2010

By Sidney Katell

This report covers the period January 1962 through December 1962; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fourth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load evolved in the preparation shared equally. Tile abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from tile following sources:

Jan 1, 1963

By Mark Flower

A 20L ignition test chamber has been used to test suspensions of 7 UK and world traded coals in air and O2/CO2 mixtures typical of oxy-combustion conditions. The coals varied in rank from sub-bituminous to bituminous and were tested in varying concentrations from the ignition limit to 400g/m3. Following each successful test the combustion residue was collected, weighed and analysed within a thermogravimetric analyser, allowing Q factors to be estimated. The ignition limit varied slightly in air, but was mostly around the 200g/m3 level. With the exception of Coal C, which was much harder to ignite, it correlated roughly with coal rank. The ignition limit changed significantly with O2 concentration when in mixed O2/CO2 gases. Only a few high volatile coals ignited in 21% O2/CO2 v/v, and then only with a 2500 J, rather than a 1000J, igniter. An increase in O2/CO2 levels to 30 or 35% gave ignition patterns similar to those carried out in air with a further increase to 40% having little additional effect. In addition the minimum ignition concentration decreased with increase in O2. Heterogeneous combustion or gasification of the coal by CO2 appears to be confirmed by comparing weight loss results for air and O2/CO2 mixtures respectively for an equivalent peak pressure rise.

Jan 1, 2009

By Th. G. Sahama

This paper contains some new heat-of-solution measurements of geikielite (MgTiO3), limonite (FeTiO3), fayalite (Fe2SiO4), and a natural forsterite in mixed acid (HF +HCl) and gives the results of a thermodynamic attack on the problem of stability of geikielite in rocks.

Jan 1, 1949

By Raymond B. Ladoo

"The talc and soapstone deposits of Vermont have been worked more or less continuously for nearly 100 years, but all of the early efforts seem to have been directed toward the production of slabs for foot warmer, and other similar uses. Altho soapstone of good quality occurs at several places, much of the material first utilized was really talc and was not massive enough to be cut successfully. The grinding of talc in Vermont seems to have commenced in about 1902 and has shown continuous growth since that time. Statistics compiled by the Geological Survey in Mineral Resources of the ,United States show that the production of talc in Vermont has increased, from 8,978 short tons valued at $65,525 in 1905 to 93,960 short tons valued at $625,150 in 1917. Until 1917, New York was the leading producer in both tonnage and value with Vermont second, but in 1917, Vermont took the lead in tonnage produced, although not in value, with a production of over 47% of the total tonnage produced in the United States and over 35% of the world's pro-duction. This increase in production will probably be continued, though possibly at decreased rate, for the reserves of talc In Vermont are large.Active talc mines and mills in Vermont are found in four districts: Chester, Windsor County; Rochester, Windsor County; Waterbury, Washington County; and Johnson, Lamoille County, These mines and mills are distributed as shown in the following table:While there are a great many other known deposits of talc and soapstone in Vermont, some of which have been worked, those listed above are the only ones which have survived and are producing on a commercial basis. The closing down of many mines and quarries, for example, those at Perkinsville, Stockbridge, Reading, Cavendish, and Athens, has been attributed to several causes. Of these causes the most important seem to be exhaustion of the deposit, poor grade, long haul to the railroad, poor management due to lack of knowledge of mining methods and failure to consider talc mining strictly as a business proposition. The companies which are now operating with greatest apparent success are those which have realized the present and future possibilities of their industry, and have invested sufficient capital in both equipment and personnel to establish their companies on a firm business basis."

Sep 1, 1919

By David Schlain

"INTRODUCTION Electrolytic manganese is produced by electrolysis of a solution of manganese sulfate and ammonium sulfate in a diaphragm-type cell, metallic manganoese being deposited on the cathodes and sulfuric acid produced at the anodes. The spent electrolyte is used to leach fresh ore that has previously been subjected to a reducing roast; the resulting leach liquor is purified and returned to the cell.The leach liquor produced at the Bureau of Mines pilot plant 3/ at Boulder City, Nev., contains 135 to 140 grams of ammonium sulfate and 32 to 36 grams of manganese (as sulfate) per liter, and has a pH of about 2.5. After neutralization to a pH of 6.4 to 6.6 with ammonia and thickening, 0.10 to 0.15 gram of hydrogen sulfide per liter is added to the liquor to precipitate the heavy metals, and after 15 to 30 minutes the precipitate is filtered off. Residual sulfides and colloidal material are removed by ferric hydroxide formed by adding a small amount of ferrous sulfate to the solution at a pH of 6.5 to 7.0 and passing air through it. The solution is then filtered and clarified as a precoat filter. Finally, 0.1 gram of sulfur dioxide per liter is added, and the solution is electrolyzed in an anode-in-diaphragm cell. The spent electrolyte coming from the cell contains approximately 10 grams manganese, 135 grams ammonium sulfate, and 45 grams sulfuric acid per liter."

Oct 1, 1946

By Chas. G. Maier

The bright annealing of copper is an industrial practice of considerable importance. In connection with this process, equilibrium concentrations of carbon monoxide and dioxide, which may exist in contact with copper and cuprous oxide at elevated temperatures, are of interest. Data obtained at the Pacific Experiment Station of the U. S. Bureau of Mines enable estimates of these equilibrium concentrations to be made in two independent ways. Although the publication of final data on one method can not take place until certain further experimental work is accomplished, repeated requests which the Bureau of Minus has had for data relative to the annealing and deoxidation of copper justify the present preliminary report. This paper deals with the calculation of gas concentrations in the reduction of cuprous oxide, using more scientific data which will be published later, and refers especially to those conditions of temperature and concentration of practical implication, and from which critical limits ensue.

Jan 1, 1929

By Raja V. Ramani, Robert L. Frantz

"The House/Senate Joint Conference Committee has instructed the Bureau of Mines to have the Advisory Committee on Mining and Mineral Resources Research review on an annual and simultaneous basis each generic mineral technology research center (GMTC). In order to accomplish that review promptly and uniformly, committee members have revised and approved an in-depth questionnaire. That document formed the basis of their review. The information provided by that questionnaire was an important factor in their recommendations concerning the future direction of the program; a presentation was made at the last National Plan Update.The comprehensive nature of the questionnaire and the scope of the information contained therein make it an excellent retrospective of the Center. Having a clear vision of where the Center has been and knowing where it is now will help guide it into the future. It is felt that such a detailed view of the Center's facilities and research program will be of value to Center personnel and Advisory Committee members.Each aspect of the questionnaire has been examined, answered in detail, and documented throughly. With the completed questionnaire as a guide, this volume examines the research program, Center personnel presently active on GMTC projects, number of graduate degrees granted with GMTC support, GMTC publications, degree of individual interaction, technology transfer, the reference center, GMTC equipment and facilities, and any envisioned plans for future research. It is hoped that this volume will serve as a review of the years 1984-1988, the first four years of the Center's operation."

Aug 31, 1989

By A. U. Miller

Protection against fire is a greater problem at a coal mine, than at an ordinary industrial plant. Generally mines are located in isolated districts and do not have the protection of city fire departments; consequently fire fighting aquipment must be installed by the mining company. Fire protection around a mine is just as essential as it is in the city.. and undoubtedly is more important if the fire should be underground where many lives would be endangered and all means of escape cut off. A surface fire can generally be attacked from any angle, but an underground fire can be attacked only as conditions will permit.. U. S. Bureau of Mines engineers have investigated many serious mine fires that undoubtedly could have been extinguished in incipiency if a fire extinguisher or fire hose and water had been readily available. In past years very little attention was given..to fire fighting equipment and organization around mines, but in recent years three gen a derde hange of opinion among many of those engaged in mining, and nearly all up-to-date mining companies now have some kind of fire protection about their mine Probably the first company in Illinois to install regular fire fighting equipment and effect a fire fighting organization at its mines, was the Madison Coal Corporation, which operates several mines in Illinois. The main office of this company is in Chicago and the general field office is at Glen Carbon, Ill.

Jul 1, 1930