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By M. W. Von Bernewitz

The Bureau of Mines receives frequent requests for information on the treatment of mercury ores, but as its own and almost all other publications on mercury are out of print, the Bureau has prepared this circular on the metal for the prospector and operator of small mines and plants. Mercury, commonly though improperly termed ?quicksilver?, is the only common metal that is liquid at ordinary temperatures. Mercury is used in the amalgamation of gold and silver, in power boilers, explosives, friction-less bearings, laboratory apparatus, lamps, medicine, paint, rectifiers, and for ?silvering.? The last mentioned is being superseded by silvering with silver. The use of mercury boilers may increase when they are thoroughly understood, but amalgamation is -being replaced to some extent by the use of corduroy and other collecting mediums, such as jigs and flotation cells.

Jan 1, 1937

By G. W. Adams

Foreword While the literature on radium is voluminous, there is no single publication available from Canadian sources which attempts to cover at all fully the world radium industry. The comparatively recent developments in the Wilberforce area, and the consequent arousal of public interest in radium, seemed to call for the publication of such a paper which would be intelligible to the layman. To satisfy this apparent need, the writers submit this paper which contains material derived from various sources, and for which the writers make no claim of originality. Direct references are made throughout the paper to sources of information.

Jan 1, 1931

By J. S. McNabb

"A search for manganese ore by core-drill exploration was carried out by the Bureau of Mines in the Philipsburg mining district in Granite County, Mont., in 1939 and 1940. This work was based on detailed studies of the manganese ore bodies of the district previously made by the Geological Survey.In 1949 further search for manganese in the district was deemed advisable. Diamond drilling was begun the following year as a joint program by the Geological Survey and the Bureau of Mines with the primary purposes of probing ore-leasing structures and extending the limits of known ore bodies. A secondary objective was to test a geologic theory based on a new conception of manganese-ore localization. The exploration targets were designated and the drilling results interpreted by the Geological Survey, and the Bureau of Mines was responsible for the drilling, sampling, and core handling. Improved drilling equipment and methods were utilized in an effort to obtain better core recoveries than resulted from the earlier drilling campaign.The Philipsburg mining district, Granite County, Mont., is 27 miles south of Drurrnnond, about 45 miles airline northwest of Butte, and 1 mile east of Philipsburg. During the course of the investigation patented lode-mining claims owned by the American Machine & Metals, Inc., the Contact Mines, Inc., and the Moorlight Mining Co. were diamond drilled.The district has been an important source of domestic manganese dioxide ore since local recognition of the mineral's importance during World War I. Peak annual output in 1918 of about 127,000 tons of manganese ore was utilized principally by the steel industry. A small but relatively steady output has persisted to the present to satisfy demands by battery manufacturers for battery-grade manganese dioxide.The known manganese deposits of the district are in sedimentary rocks of Paleozoic age. These rocks lie along a north-trending anticline traversed by a series of east-west tension veins. The east flank of the anticline terminates at a steep-dipping fault contact against a small granodiorite batholith.Replacement deposits of manganese oxides and carbonates occur locally in or closely associated with tension veins cutting calcareous rocks, or adjacent to the intrusive. Rhodochrosite has been a common accessory mineral in deposits valuable chiefly for lead, zinc, and silver. Some of the replacement deposits characteristically are irr2gular in outline, whereas others have fairly regular walls marking the limits of favorable beds."

Dec 1, 1955

By F. D. Everett

The Federal Bureau of Mines reviewed the status of tungsten deposits of Utah in 1959. Industrial requirements of tungsten during emergencies have exceeded the domestic supply, and a knowledge of the sources of this strategic element may be helpful in the future. Tungsten occurs as the mineral scheelite in deposits that have been developed or explored on approximately 60 properties in 10 of the Great Basin ranges of Utah, none of which were being worked in 1957-59. Ores from most of the productive areas are similar in that they are contained in tactite deposits on or near the contact of calcareous and acidic intrusive rocks. The tactite ores consist predominantly of the silicate minerals garnet, epidote, and diopside and the carbonate rocks limestone or dolomite. Scheelite, where present, is disseminated irregularly in the tactite. Tungsten ores from Utah mainly have been produced from small deposits worked in World Wars I and II and the Korean campaign. The ores were either hand sorted to a grade ranging from 0.5 to 1.0 percent tungsten trioxide (W03) or were beneficiated in small mills to higher grade concentrates. The largest reserve appears to be in the area of the Notch Peak intrusive in the House Range, Millard County. A large part of the reserve in the House Range is mineralized tactite containing 0.2 to 0.3 percent W03. Research on flotation by the Bureau of Mines has indicated a method of concentrating scheelite in tactite ores that average 0.25 percent W03, with at least 85 percent recovery. The concentrate assays more than 5 percent W03 and can be processed into artificial scheelite ready for industrial use.

Jan 1, 1961

By Margarete Kalin

"Difficulties arise in implementing environmental technologies in the mining sector because important fundamental processes, which lead to the environmental degradation, are ignored. Weathering rates, the role of bacteria in the process and the incomplete application of the matching principle of accounting at the time the mining disturbance take place. Mining is a multi-stakeholder activity and the environmental problems have multivariate dimensions also effecting process.The limiting factors in the contaminant generation process are the transport of oxygen by advection, convection or diffusion in air or water and the associated microbial activity. Weathering products are transported from the mineral surface by atmospheric precipitation to surface and groundwater. This contamination takes place at different rates, requiring a long time to evaluate technological choices.Restoration efforts have to focus on slow reaction rates in the contaminant generating processes. Technology, which does not address the reaction rates and is selected based on inappropriate time scales, will not provide long-term solutions. Natural approaches to reduce acid generation, based on Ecological Engineering principles have required decades of research and field testing, but now show promise in addressing the cause of AMD and ameliorating its effects."

Jan 1, 2005

By A. Soderberg

This paper describing the mining practice at the Utah Copper Co., Bingham Canyon, Utah, is one of a series being prepared by the Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The Utah Copper Co. operates the low-grade open-out copper mine at Bingham Canyon, Utah, which is 30 miles in a southwesterly direction from Salt Lake City. In addition to the mine the company operates two flotation concentrators, the Magma plant and the Arthur plant, which have a combined capacity at maximum metallurgical efficiency of 60,000 tons daily. The concentrators are at Magna, about 18 miles from the mine. The company operates its own standard-gage railway, known as the Bingham and Garfield Railway, between the mine and the mills (fig. 1). Concentrates are smelted at the Garfield smelter of the American Smelting and Refining Co., situated 4 miles from the mills.

Jan 1, 1930

By Nicholas J. Grant

It is the purpose of this paper to examine a number of the recent developments in powder metallurgy, being most concerned with those which are yet to prove themselves rather than those which have achieved commercial maturity. Such developments include the production of very much coarser and very much finer powders, down to the near-micron size range. Also considered are activated sintering, direct powder rolling and extrusion (both hot and cold), brazing and welding, hydrides of reactive metals, oxide dispersion strengthened alloys and theoretical evaluations. Introduction T HERE surely can't be very much argument with the fact that powder metallurgy has made large advances on many fronts during the past ten or more years (1). These advances have taken place in raw materials, in processing, in product development and in a better understanding of many of the phenomena which occur in the various steps involved in powder metallurgy. It should be clear, in view of such growth, that it will not be possible to highlight all of the new developments in the present paper. Many of these developments,

Jan 1, 1965

After a stagnant performance in 1982, gross national product (GNP), industrial production, and employment increased during 1983 in nearly all industrial nations, with the U.S. performance generally leading the uneven worldwide recovery. Real U.S. GNP increased 3.3 percent in 1983 (table I). Although investment in nonresidential structures declined, total nonresidential fixed investment in the United States was up 1.5 percent following a 1982 decrease. The increase in worldwide industrial activity and demand in 1983 put greater pressure on prices in many countries. Prices increased from less than 3 percent in the Federal Republic of Germany, Japan, the Nether-lands, and Switzerland to as much as 10 percent in nearly all the other Organization for Economic Cooperation and Development nations. The annual inflation rate in the United States was 4.3 percent (based on the GNP fixed-weight price index).

Jan 1, 1984

By A. H. Shoemaker

This paper describing the mining practices at the Old Dominion mine, Globe, Ariz., is one of a series being prepared by the United States Bureau of Mines on mining practices, methods, and costs in the various minim districts in the United States. The Old Dominion mine is situated in the eastern port of the Globe-Miami district, about 1-1/2 miles north from the center of the town of Globe. An average of nearly: 1,200 tons per day was mined during 1928. The prevent production is about 1,500 tons per day; of this amount,, approximately 100 tons is direct-smelting ore that is shipped to the smelter at Miami and 1,400 tons milling ore which is treated in the company?s concentrator at Globe. About 600 men are employed at the mine.

Jan 1, 1930

By W. P. Haynes

To evaluate the potential use of battery-powered vehicles, the Bureau of Mines studied the performance of a battery-powered truck propelled by a 9.6 kw dc motor in considerable detail under various driving conditions. Some of the factors investigated were: Gear ratios, payload (1,468 lb maximum), road grade, stops made per mile, and charging time. With the exception of some difficulty with brush wear, operation and maintenance of the truck was generally trouble-free. On range tests carrying an 868-lb payload a distance of about 50 miles at an average speed of about 19 mph in normal driving, the Bureau's battery-powered truck averaged 1.6 to 1.9 miles per ac kwhr input. Stop-and-go tests indicated that prospects for the use of battery-powered trucks in house delivery service within city limits are good; performance of the Bureau truck was sufficiently high for that type of service. The estimated power cost of 2.65 cents per mile while making 10 stops per mile was attractively low from the standpoint of fuel costs.

Jan 1, 1967

By H. R. Shell

To obtain a better understanding of the crystallization of fluoride containing amphiboles from melts, an investigation of the range of stability between fluoramphi-boles and other minerals was conducted by the Bureau of Mines. This study has shown that the stability of fluoramphiboles is strongly influenced by both fluoride concentration and isomorphic replacement. Over 150 reactions were made with different compositions and reaction conditions. substitutions attempted and the phases that formed when the composition was crystallized by cooling from the melt are discussed. The attainment of equilibrium in these multicomponent systems is not claimed. Many ions that would be expected to enter the amphibole structure instead resulted in crystallization of phases other than amphibole. Those compositions that resulted in a high yield of acicular fluoramphibole by crystallization from the melts are shown in table 2. The fluoramphiboles obtained from melts typically had an acicular crystal habit and a hardness of 6 to 7 on the Mohs' scale. Although many had relatively high length to cross section ratios, none were fibrous; it was concluded that the possibility of synthesizing a fibrous fluoramphibole from a melt was low. However, many compositions can be crystallized into a tough, hard, impact-resistant mass of interlocking acicular crystals.

Jan 1, 1958

By George Quackenbos

The principal objective of this Program is the design, fabrication and testing of an Environmental System for operation in underground mines, to assess the effect of various mining systems on the contaminant levels near the mine face and within return airways. In order to determine the effect on airborne contamination in mines resulting from the development of new mining techniques, equipment and control systems, a Comprehensive Monitoring System is required to assess such contamination levels at critical and strategic locations and relate this information with ventilation parameters. The three variables to be sensed on a continuous basis are airborne dust concentration, methane concentration and ventilation air velocity. Each Monitoring Station will consist of a self-contained unit containing a power source and sensors to monitor the three above mentioned parameters. Ruggedness, reliability, ease 'of operation and intrinsic safety are important design objectives. Data gathered by each Monitoring Station will be fed to a Central Data Acquisition System by means of a portable transfer unit.

Jan 1, 1982

By Hans von Michaelis

The renaissance in extractive metallurgical practices for gold and silver recovery is far from over. This is one conclusion of a three year investigation into innovations in Cold & Silver Recovery by Randol International Ltd. (1981, 1983). The six volume reference report reviews a host of new processes and innovative applications of older metallurgical practices. Some of these were summarized by von Michaelis (1982, 1982a). There are several reasons to expect this renaissance to continue. One reason is the nature of gold and silver deposits. The list of known occurrences of These metals is very extensive. There are literally tens of thousands of prospects but over 99% of these are too low grade, too small or too refractory for a viable operation employing conventional processing.

Jan 1, 1983

By Hugh W. Evans

Many reports and papers have been delivered on projects under construction or already in operation, but we believe there are few that have been written about projects yet to be built specifically dealing with advanced mine and environmental planning. This paper describes such planning for Atlantic Richfield Company's Black Thunder mine. Project planning is a cyclic phenomenom involving four broadly overlapping planning steps (Figure 1). The demands of the public include needs that can be satisfied through planned resource development. Using a base of information that partly exists and must in part be gathered and updated, the preplanned development can be, evaluated. The evaluation process, with built-in environmental constraints leads to an implementation procedure. Implementation results in the development, including the release of the affected area to other public demands that follow.

Jan 1, 1975

By J. Douglas Causey

In 1987, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied 13,374 acres of the 14,994-acre Ireteba Peaks Wilderness Study Area (NV-050-438) in order to evaluate its identified mineral resources. The study area is located in Clark County, NV, about 4 miles south of Nelson, NV. No identified resources were found within the Ireteba Peaks study area, although there are identified subeconomic resources just outside of the study area boundary. Most of the area is underlain by Tertiary granitic rocks, which apparently postdate mineralization. The area is virtually surrounded by mining districts with mines developed in older rock units. On the north side, quartz monzonite, volcanic tuff, and tuffaceous sediments in the Eldorado mining district host deposits of gold, silver, copper, zinc, and mercury. On the south side, Precambrian gneiss, intrusive andesite porphyry, and hornfels in contact with Quartz monzonite in the Searchlight mining district host gold, silver, copper, and lead deposits. The Newberry mining district to the southeast had copper, gold, and silver mineralization in Precambrian gneiss and andesite.

Jan 1, 1988

By Gregory J. Chekan

This Bureau of Mines report presents three methods for designing bulkheads to impound water underground: (1) thin and thick plate design; (2) South African plug design; and (3) single and double bulkhead seal design. Related areas critical to the long-term effectiveness of underground water impoundments are also addressed. These include bulk-head anchorage, concrete specifications and placement, the grouting of permeable strata, and the sizing of barrier pillars. A case study involving hydrostatic tests conducted on a single bulkhead seal constructed in the Safety Research Coal Mine of the Bureau's Pittsburgh Research Center is presented in an appendix.

Jan 1, 1985

The Colorado portion of the Rio Grande rift is clearly defined physiographically from the south in the San Luis valley northward to the latitude of Leadville where sediments of the Dry Union Formation (Tweto, 1961) accumulated within the subsiding rift zone. To the north of Leadville is a system of faults active in the late Tertiary, including the Mosquito fault that offset a portion of the Climax mineralization (Wallace et al., 1968). Tweto (197B) describes remnants of Dry Union Formation against the Mosquito fault north of Dillon in the Blue River valley, so it is apparent that the rift and associated sediments extended well to the north of Leadville. Kelley (1952, 1954, 1956) and Chapin (1971) have noted in New Mexico that the Rio Grande rift is a series of en echelon basins, offset to the east, with constrictions connecting them (Fig. 1). In Colorado the structural basins are offset to the west. The net effect of all the rift zone basins in New Mexico and Colorado is an arcuate pattern (Fig. 1) abutting the Colorado Plateau and Sari Juan Volcanic Province on the west. The width of the rift system gradually decreases northward to about Leadville where rift definition is not apparent.

Jan 1, 1987

By Allen V. Heyl

This old district is a major zinc and lead source and minor copper and barite source. Ores are chiefly in the Galena Dolomite and in limestones and dolomites of the Decorah and Platteville Formations, all of Middle Ordovician age. Locally, deposits have been mined from Lower Ordovician dolomites and Upper Cambrian sandstones. Small deposits of lead, zinc, and iron sulfides have been found in Upper Ordovician Maquoketa Shale and in Lower and Middle Silurian Edgewood, Kankakee, and Hopkinton Formations. No post-Precambrian igneous rocks are known in the region, and the granitic and metasedimentary Precambrian basement rocks unconformably underlie the district at depths of 1500 to 2000 feet. The strata are gently flexed and faulted, probably largely the result of gentle compressive and rotational adjustments in the underlying crystalline basement, especially along lineaments between basement blocks. Folds of three orders ·of magnitude are recognized, and many related reverse, strike-slip, and normal faults of small to moderate displacements are present. Zinc-lead deposits are commonly linear, arcuate, or elliptical in plan. Most ore occurs as vein fillings in fractures and as breccia fillings and lining vugs, but some is in bedded replacements and impregnations of wall rocks. The ore is in shears, small reverse and bedding- plant faults, joints, and solution-slump structures related to intermediate and small folds. The main primary minerals in their general sequence of deposition are quartz, illite, dolomite, pyrite, marcasite, cobaltite(?), sphalerite, galena, chalcopyrite, millerite, barite, and calcite. Wall-rock alterations include solution of the carbonate rocks, silicification, dolomitization, clay alteration, and sanded dolomite. Oxygenisotope, trace-element, lead-isotope, and sphalerite- stratigraphy studies are in progress. Fluid inclusions in sulfide and gangue minerals are filled with concentrated brines at 120° to 40°C. Sulfides are directly replaced by supergene minerals above the water table at 50 to 100 feet in depth. In this relatively cool climate and limestone environment, smithsonite is in pseudomorphs after sphalerite; solution transport and redeposition of supergene minerals are rare. Ore genesis is postulated by rising hot-water solutions-a mixture of heated connate, magmatic, and meteoric waters.

Jan 1, 1968

By W. Bakiewicz

The Lower Indus Basin deposits form a substantial unconfined alluvial aquifer of excellent quality. This aquifer contains basically highly saline groundwater, overlain in places by considerable amounts of freshwater whose origin can be traced to the present and historical courses of the River Indus. In the past the main source of groundwater recharge has been direct river seepage and water tables were generally deep. Since the establishment of a perennial irrigation regime however, deep percolation from the increased irrigation supplies has predominated and the water-table has risen to within a few feet of the surface. The river system itself is being progressively developed for irrigation and very shortly a situation will arise where the entire low winter flow will be utilised. Fresh groundwater will then be exploited to supplement the surface supplies, and at the same time a drainage system, mainly based on wells will be used to stabilise the water-table at safe depths. This paper discusses some of the methods used to ensure optimum-economic development of the fresh groundwater and describes the general design philosophy evolved by the authors firms for both irrigation and drainage wells, with respect to both well configuation and operation. Water quality standards are discussed in as much as they affect subsequent use of the groundwater. A few particular aspects are considered, including that of the values of the relevant aquifer constants, the construction of wells and the determination of screen losses. A major problem solved during the Lower Indus Project investigations has been the design of wells to-produce fresh water from layers overlying saline water. This solution is also discussed.

Jan 1, 1967

By M. H. Salsbury

This report describes the tunneling at the Leadville drainage tunnel, which was resumed in September 1950 with funds made available in the 1950 appropriation of the Department of the Interior. It brings up to date the account of the first project, carried on from December 1943 to August 1945, published by the Bureau of Mines which supervised both the first and second projects. In this report Leadville mining history, particularly related to drainage efforts, and the possibilities for future mine drainage are discussed briefly. An account of the second project, including a description of the operating cycle, exploratory drilling done as a safety measure, surveying procedures, geology, cost data, and other pertinent information, completes the report.

Jan 1, 1956