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The Bureau of Mines Minerals Information organization collects worldwide data on virtually every commercially important non fuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. This data collection activity was instituted by the 47th Congress in an appropriations act of August 7, 1882 (22 Stat. 829), to place the collection of mineral statistics on an annual basis. The most recent authority for the Bureau of Mines Minerals Information activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress), which strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1984

By B. J. Scheiner

The Federal Bureau of Mines investigated an electrolytic oxidation procedure for extracting lead, zinc, copper, and silver from lead-zinc concentrates. Concentrates slurried in brine were pumped through the anode compartment of electrolytic cells equipped with selective ion diaphragms. Hydrochloric and hypochlorous acids generated in the anode compartment converted the metal sulfides in the concentrates to soluble metal chlorides, sulfate ion, and elemental sulfur. Metal extractions of 92 to 100 pct were obtained from lead-zinc concentrates at an energy consumption ranging from 1.5 to 5.0 kW-hr/lb metal extracted. Sodium hydroxide was formed in the cathode compartment at a current efficiency of >99 pet. Silver and copper were extracted from refractory tetrahedrite minerals, but the process entailed a relatively high energy consumption. Sealing the top of the diaphragm cell utilized the chlorine more effectively, thereby reducing energy consumption 10 to 50 pct.

Jan 1, 1975

This report presents the results of a study of Kennecott Copper Corporation?s Chino leaching dump at Santa Rita, N. Mex. The stability studies described herein were performed on only one cross section of the leach dump, utilizing data obtained from drilling, sampling, and testing, which was limited in nature. The first part of the report contains a discussion of site geology and seismicity, pertinent information on the waste material disposal system and leaching method, a discussion of the waste embankment characteristics, a summary of the engineering analyses, and a bibliography. The second part (appendices) contains basic geologic and engineering data supporting the discussions in the first part.

Jan 1, 1974

By E. D. Gardner

A custom gold and silver plant is one that treats ores for a fee. Usually such plants are located in mining districts and treat local ores. Ores of milling grade generally can stand only moderate transportation charges. These plants are scattered throughout the West. Most plants now doing a custom business originally were built by mining companies to handle ores from their own mires. As excess mill capacity became available ores from neighboring properties were treated, vainly as an accommodation. Later, as their own ore bodies became depleted, the mills were operated entirely on a custom basis. A few plants pull ore from their own mines only when the supply of custom ore is insufficient to keep the mill operating. Some of the present custom plants were built for custom work alone. Although built originally to treat the ores of the Golden Cycle mine, the Golden Cycle plant at Colorado Springs, Colo., soon became a custom mill and has been operating successfully for many years. It is the largest gold mill in the Western States and. treats Cripple Creek ores, from which most of its tonnage still comes. The plant is equipped to treat a great variety of ores and receives shipments from a wide area. It competes with smelters in Colorado, as it has a roasting plant to prepare sulphide concentrates for treatment in its cyanide plant. Most custom mills, however, are not adapted for more than one or two kinds of ore. Gold occurs in its ores both in the metallic state (free) and locked up in sulphides. It also occurs in a few places, notably at Cripple Creek and a few other Colorado districts, as tellurides. Mien the gold occurs in the native state, the ores is said to be free-milling and can be recovered by amalgamation. Usually, however, some subsidiary treatment is required to make a satisfactory extraction. Amalgamation generally was followed by tabling in the earlier mills; at present, flotation has replaced tables at many places. As depth is reached in raining and the workings extend below the oxidized zone the character of the ore usually changes, or, as the miners say, "it gets base". Since the advent of flotation, the average recovery of gold in base ores has been improved-greatly. Cyanidation is applied to some types of both gold and silver ores. The recovery by cyanidation is in general considerably higher than by other methods in vogue and in addition has the advantage of making a finished product which can be sold directly to the mist, thus obviating smelting charges on concentrate and discounts

Jan 1, 1935

By G. W. Birge

The Bureau of Mines investigated the effect of temperature on the mechanical strength of cokes of the type normally used in blast furnace operations. Eight samples of industrially produced cokes were subjected to ASTM tumbler tests at temperatures as high as 1,100° C (2,012° F); these temperatures had no significant effect on tumbler results for cokes with stability indexes of 40.6 to 59.9. Two foundry cokes which were tested at only one elevated temperature (900° C) decreased slightly in tumbler stability. Iron are pellets made from a variety of ores and by various industrial methods were not significantly affected by temperature when tested in an oxidizing atmosphere at 1,000° C (1,832° F) by the tentative standard ASTM method.

Jan 1, 1966

By W. T. Wertman

A research program to aid development of better and more efficient methods for producing petroleum and increasing its ultimate recovery from underground formations is an integral part of the work of the Bureau of Mines on conservation of the Nation's natural resources. Economic, efficient production of recoverable oil and gas from a reservoir depends to a great extent upon the best and most accurate information that can be obtained from a study of the reservoir rock and its fluid contents. Information on oil and water saturation is pertinent and essential in wildcat, extension, and pool wells for good reservoir operations and prediction of performance. This report presents results of an investigation by the Bureau of Mines of core recovery and degree of drilling-fluid contamination occurring during cable-tool coring operations using oil-base mud. Representative core samples were obtained from 6 major oil-producing sands in 8 fields of West Virginia, Pennsylvania, and New York. Field-mixed, oil-base drilling mud was used for the first coring test, and lightweight, premixed oil-base mud, with an organic chloride tracer added, was used in coring eight other wells. Tracer analyses were made to determine contamination of core by drilling-fluid filtrate. Core analyses, including oil and water content and minimum interstitial water-saturation tests, were made on selected core samples to compare and evaluate water saturations determined by the two methods.

Jan 1, 1958

By E. H. Denny

The coal and metal mines of the United States furnish this country with a large part of the fuel and material necessary to support our industries and thus make possible the welfare and prosperity of our people and even the continuance of our present-day scale of civilization. Mining companies furnish material to industry with one general purpose in mind -- the making of a profit on their work. Efforts are being made successfully and continually to reduce operating costs, to increase production per man, and to perform work as far as possible mechanically and with more efficiency. These efforts are made primarily to reduce costs, to increase production, or to do both - in other words to make more profits or more certain profits. In the endeavor to reduce expense companies are considering more and more the factors which enter into costs of production, among them the factor of accidents and their cost. This paper endeavors to estimate the approximate cost of accidents to the mining industry in order to present the saving possible through accident reduction or elimination.

Jan 1, 1929

By Leland E. Paulson

This investigation examined the feasibility of altering the inorganic component of North Dakota lignite by ion exchange. Lignite of specific size consist was washed with various ionic solutions and examined for evidence of exchange. Ions of higher valance substituted preferentially at equivalent concentrations. Results indicate that a major portion of the inorganic material associated with lignite is combined in exchangeable form with the organic component. Particle size of the treated coal is a critical factor in determining the rate of exchange. The data indicate that monovalent ions are easily replaced by divalent and trivalent ions, and the presence of ionic material in slurries containing finely divided lignite significantly increases filtration rates.

Jan 1, 1968

By H. B. Brunot

The United States Bureau of Mines under provisions of Schedule 2C4 issues approvals covering complete operating units such as loading machines, room hoists, and storage-battery locomotives. Certain manufacturers design and build entire machines. Other manufacturers purchase a part or all of the electrical accessories from manufacturers of electrical equipment and make up permissible units by assembling them. Before the assembler purchases electrical accessories for use in such contemplated units he may require certain information from the accessory manufacturer as to whether the particular accessories are suitable for assembly in his proposed permissible outfit. To aid accessory manufacturers in marketing their product, a provision was incorporated in Schedule 20 whereby tests might be made on individual accessories and reports rendered as to the suitability of a given accessory for use in permissible assemblies.

Jan 1, 1935

By Robert J. Hundhausen, Robert M. Gammell

"INTRODUCTION Several mining properties in the Pine Creek area of the Coeur d'Alene mining region of Idaho were examined by engineers 3/ of the Bureau of Mines in 1942. As a result, a broad program of exploration was recommended for the area, particularly in the eastern end, where chances for the discovery of new ore shoots seemed favorable. This report describes the work done and the factual information obtained by the Bureau of lanes.ACKNOWLEDGMENTSIn 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 Be Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch,. C. C. Ralston, chief, analyzes samples and performs beneficiation tests.The exploratory work at the Sidney mine was part of the activities of the Albany Division of the Mining Branch, S. H. Lorain, chief. Field work was under the direction of R. M. Gammell.Chemical analyses included in this report were performed at Reno, Nov., under the direction of A. C. Rice, acting engineer in charge, Rare and Precious Metals Experiment Station, Bureau of Mines. The ore-dressing tests were made under the direction of S. R. Zimmerley at the Bureau of Mines laboratory in Salt Lake City, Utah.The cooperation and assistance given by the owners of the Sidney Mining Co. is gratefully acknowledged."

Feb 1, 1948

By J. M. Davidson

The potassium mineral polyhalite (K2SO4.MgSO4.2CaSO4.2H2O) found in large deposits in western Texas and southeastern New Mexico is associated with varying amounts of halite (sodium, chloride, NaCl) and anhydrite (calcium sulphate, CaSO4). Although the anhydrite, because of its low solubility and slow rate of solution, is relatively inert, the halite is dissolved immediately in any process solution with which the polyhalite comes in contact. Limited quantities of sodium chloride in the liquors used for the hot extraction of polyhalite materially improve the results obtained, but only a very small sodium chloride content may be desired in the entering polyhalite in other procedures, such as Bureau of Mines process. In all of the processes suggested for the recovery-of potassium sulphate from polyhalite the control of the sodium chloride content will be desirable, if not absolutely essential to efficient operation.

Jan 1, 1934

By J. R. Thoenen

This circular is part 2 of the third subject (entitled "Excavation") of a series summarizing; the technical problems involved in the production and preparation of sand and gravel. Part 1 discussed the use of power shovels, draglines, and excavator cranes. This paper discusses the use of the power scraper, slackline cableway excavator, and hydraulic monitor, and part 3 will discuss the use of various types of dredges. Subsequent papers in the series will discuss the use of haulage equipment, the application of both excavating and haulage equipment to various types of deposits, and operating costs. THE POWER SCRAPER The power scraper is a younger member of the various forms of gravel excavators. It is a mechanized enlargement of the slip scraper and other scrapers which depend upon animals for power and has a greater range of operation from a single set-up than any other excavation unit except the slackline cableway excavator.

Jan 1, 1935

By H. O. Poppleton, F. E. Block

This investigation was made to develop a method of preparing high - purity thorium metal in quantities up to 20 kilograms per batch . Several methods for the preparation , purification , and reduction of thorium tetrachloride are discussed . Thorium tetrachloride was prepared by chlorination of decomposed thorium nitrate or oxalate with carbon tetrachloride or phosgene . tion of the crude tetrachloride was achieved by multiple distillations or by filtration of the molten chloride . It was found that high - purity thorium metal could be prepared by sodium reduction of thorium tetrachloride if chloride of sufficient purity were available . Byproduct salts and excess reductant were removed by vacuum distillation , and the resultant thorium metal sponge was consolidated by consumable - electrode or fixed - electrode arc melting . It was demonstrated that metal prepared by this method could be fabricated into bar , rod , or sheet , at room temperature .

Jan 1, 1964

By D. W. Frommer

Processing of nonmagnetic taconites by selective flocculation-des liming and anionic flotation of calcium-activated silica has been investigated using innovative procedures as a means of improving operating costs. Areas chosen for cost-cutting evaluation were grinding, fine screening, and water conservation and reclamation. The investigation was performed on Marquette range nonmagnetic taconites in the Bureau of Mines Twin Cities Metallurgy Research Center flotation pilot plant, at feed rates ranging between 900 and 1,100 lb/hr. With fully integrated water reclamation, flotation concentrates containing 65.8 percent Fe and 3.4 percent Si02 were made in the best operating period, with accompanying weight and iron recoveries of 40 and 74 percent, respectively. During this same period, the estimated cost of both flotation and water reclamation reagents was only $0.80 per ton of concentrate (1968 pricing basis). This cost is about 15 percent lower than obtained previously at this Center for flotation reagents only. The investigation demonstrated additional potential savings in operating costs of approximately $0.96 per ton of concentrate through autogenous grinding as a substitute for ballmilling. Fine screening of intermediate concentrates was employed advantageously, but the frequency of blinding may be a factor militating against use of the screen in this flotation system.

Jan 1, 1973

By Paul Sands

Single- and two-stage tests were made with 6-inch, coal-cleaning hydrocyclones to determine the effect of hydrocyclone geometry, operating conditions, and feed composition on performance. Most of the testing was conducted in an open-circuit pilot plant that had a maximum capacity of about 9 tons per hour. The coals used in the investigation had top sizes of 1/4 inch and 28 mesh. Considerable latitude was found in the range of geometry variables that could be used without affecting performance adversely, although a certain minimum ratio of overflow to underflow openings had to be maintained for best operation. Two-stage cleaning proved distinctly better than operation with a single hydrocyclone, because clean coal lost in the refuse product of the primary unit can be partly recovered in the secondary. There is an unusually great difference in the specific gravities at which the individual sizes of the feed are separated in the hydrocyclone. This militates against high efficiency because maximum yield occurs when all sizes are cleaned at the same specific gravity. The size composition of the feed and, more particularly, the size composition of the impurity have a greater influence on the efficiency attainable in the hydrocyclone than in most other types of fine-coal cleaners.

Jan 1, 1968

By Joseph Grumer

In addition to nine powder and gaseous extinguishants of propagating Pittsburgh seam coal dust-air explosions earlier evaluated,6 10 other powders have similarly been evaluated under like conditions such that wall quenching of the coal dust-air flames was virtually absent and the dust concentration was temporally and spatially uniform to within about ±5 percent. None of the newly examined extinguishants was better than Purple-K (potassium bicarbonate); the 10 of this report are anhydrite (calcium sulfate), monobasic (4 types) and dibasic ammonium phosphate, natural and synthetic cryolite (sodium fluoalumi-nate), sodium sulfate, and tricalcium phosphate. Except for anhydrite, sodium sulfate, tricalcium phosphate, and the cryolites, these materials were about equally effective, when present in relatively low concentrations (weight-percent of the coal dust-extinguishant mixture). The maximum oxygen concentration for the extinguishment of otherwise uninhibited coal dust explosions and the influence of coal dust particle size and the volatile content of the coal were also explored. For the present, the choice of the inhibitor among the good ones evaluated is not as critical as the system to be used to deploy the extinguishant against a coal dust explosion.

Jan 1, 1973

By R. L. Grayson, W. E. Wallace, T. Simonyi, J. C. Harrison

"Application of an SEM-based methodology suggests a reason for past contradictory results on the relationship between quartz and coal workers' pneumoconiosis (CWP). Results indicate that coal seams with the same bulk analysis of quartz may have different amounts of surface-availablequartz. Our research shows that the amounts of pure and surface-available quartz in a respirable dust vary directly with the rank of a coal seam, except in the case where rock materials are mined. The estimated amount of surface-available quartz therefore provides a measure of the quartz-related fibrogenic potential of a respirable dust.INTRODUCTIONFrom our previous work (Grayson, 1991), we have shown that the amount of pure quartz in a respirable coal mine dust sample appears to vary directly with the rank of the seam (using fixed carbon as the basis for comparison), except when a substantial rock parting, roof or floor are mined. Our other work (Wallace et al., 1989) showed that high-silica particles in a clay mine may generally be coated with clay, rendering the quartz core non-available for surface reaction in the lung. The combination of these findings led us to hypothesize that the coating phenomenon may indeed be present in coal mines as well, and that a rank relationship may be present regarding this phenomenon. Thus higher rank coal seams may have more surface-available quartz as well as more pure quartz particles in their respirable dusts. The scientific protocol for testing this hypothesis and the results obtained to date are discussed in this paper. Thus far, there is no reason to doubt that the relationship holds."

Mar 1, 1992

By M. A. Schellhardt

The Bureau of Mines has made periodic back-pressure tests on numerous gas wells in the Texas Panhandle field during the past several years to study the delivery capacities of the wells under different pressure and operating conditions and to determine the relationships between pressures and rates of delivery from gas wells.4/ However, information regarding the intake capacities of gas-well systems is meager, end in projects involving the flow of gas into porous-rock reservoirs it has been necessary to determine intake capacities of gas wells by trial. Accordingly the fundamental intake characteristics of natural-gas yells have been studied to develop a method for determining intake capacities under different wellhead pressures from data descriptive of the "output" or producing characteristic of the wells.

Jan 1, 1936

By H. Kim, R. W. Plummer, T. J. Stobbe, W. G. Jones

"Exposure to airborne dust in coal mines has caused respiratory disease in coal miners. The causal agent in these diseases remains unknown, although the minerals found in and around the coal seam have been implicated. Toxicological studies designed to establish the effect of different mineral combinations and concentrations are lacking because the mineral content of coal mine dust has not been defined. This paper reports the initial results of a study done to characterize the mineral content of the coal mine dust found in a mine in the Upper Freepott seam in Northern West Virginia. Coal mine dust samples were collected using 4- stage cassette impactors at nine locations in the mine. The samples were analyzed by an x-ray microdiffraction film technique supplemented by energy dispersive scanning electron microscopy. Primary size modes of about 17 to 20 micrometers from the samples collected at the haulageway and the returnside of the continuous miner were found. From the returnside of the roof bolter samples, a primary size mode of 12to15 micrometers was measured. The minerals found in high percentages were illite, kaolinite, quartz, and calcite. The distribution of minerals in inter· and intra- location samples showed wide variations. Trends in these variations are presented. Stobbe, T. J.; Plummer, R. W.; Kim, H.; Jones. W.: Characterization of coal mine dust. Appl. Ind. Hyg. 2:95· 100; 1986. IntroductionDisease-associated dusts in coal mine environments continue to afflict miners in today's modern mines. The relationship between exposure to coal mine dust and the development of various respiratory diseases has been well recognized; however, the reasons for variation in occurrence of these diseases among miners in different geographic areas,(1) rank of coal seams,(2-3) and jobs (4) remain uncertain. Several papers have reported on the causal agent in the development of these diseases. Davis (5) found that the percentage of the non-coal minerals present in the lungs of deceased miners increased as the level oi pneumoconiosis became more severe. Reisner (6) reported that cell damage caused by coal mine dust increases with the mineral and quartz content of the dust and with the geo· logical age and rank of the coals. Two studies, investigating the in vitro effects of mineral dusts. reported by Seemayer and Manojlovic (7) also obtained positive correlation between cytotoxicity and the mineral content of coal mine dust. Gormly (8) postulated that destruction of macrophages by certain mineral dusts is the first step in the development of pneumoconiosis. In 1980, Adamis and Timar (9) reported that quartz. sandstone, slate. respirable colliery dust. bentonite, illite, and some kaolins had cytotoxic effects on rat peritoneal macrophages""in vitro."" Walton,(10) however, reported that the presence of high clay, illite, and kaolin mineral exposures reversed the hazards associated with increasing quartz exposures. This finding was supported by Le Bouffant and coworkers.(11) They reported that illite present in coal mine dust strongly inhibited the pathogenic effects of quartz while kaolin had a weaker inhibitory effect."

Mar 1, 1989

By Derek Ellis

Volume II of this two-part series on Submarine Tailings Disposal (STD) as a tailings management option for coastal and island mines contains descriptions of lesser known case histories. The Misima gold mine (Papua New Guinea) and the Black Angel lead-zinc mine (Greenland) are described in some detail as the best documented cases. Atlas copper mine (The Philippines) is less fully described due to relative lack of documentation. The Misima and Atlas STD systems are working to their design criteria. At Black Angel the system adopted did not prevent contamination for a number of reasons, which are now understood. Two cases are described where STD is being developed. They are the Cayeli Bakir copper mine Turkey), and the Toquepala and Cuajone mines (Peru). There is excellent documentation available for both cases. Three case histories are described where tailings have reached the sea either through beach or river discharge. In one case the STD option has been explored (Marcopper Mine, The Philippines). In the others we explore in hindsight whether STD might have been a viable alternative using the Screening Criteria that this Volume develops - see below. The mines are Bougainville Copper Mine in Papua New Guinea, and Jordan River Mine (Canada). There is potential for STD at all three sites. Finally, the Volume presents Screening Criteria for appraising STD, based on the experience in design, operation and environmental impact reviewed in the case histories.

Jan 1, 1994