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By C. W. DeLong, L. L. Farnham, L. A. Stewart

This paper is one of a series covering mineral resources of the Nation . It describes briefly most of the known manganese deposits of eastern Arizona , which for the purpose of this report includes the counties of Navajo , Apache , Gila, Graham, Greenlee , Pinal , Pima , Santa Cruz , and Cochise . With few exceptions , these descriptions are the result of field examinations by the writers . Work on this paper was begun in May 1956 , and in the following 18 months 151 deposits were examined . The distribution of the deposits by counties is as follows : 1 in Navajo , and 1 in Apache , 37 in Gila , 4 in Graham, 13 in Greenlee , 25 in Pinal , 13 in Pima , 12 in Santa Cruz , and 45 in Cochise . In surveyed areas the locations of the deposits are described by section , township , and range and in unsurveyed areas , by approximate projections of these subdivisions . The township and range numbers refer to the Gila and Salt River base and meridian . The history, production, ownership , geologic setting , and mining methods used are discussed for most of the deposits that were visited . Probably , some occurrences have been overlooked , but all of the principal ones have been examined . Ore dressing studies were made of typical ores from several of the larger districts . The work was performed in the laboratory of the Bureau of Mines Tucson Metallurgy Research Laboratory . The results of these studies are given with the descriptions of the deposits from which the samples were taken .

Jan 1, 1961

By Thomas Fraser

IN a Nation-wide appraisal of coking-coal reserves and of the feasibility of expanding them by upgrading marginal coals, it is natural that the Pittsburgh region of Pennsylvania should be considered first. Here, where the American iron and steel industry started, the Pittsburgh coal bed is of paramount importance. The use of coke in iron blast furnaces is said to have begun with the discovery that good blast-furnace fuel could readily be made by a simple method of coking Pittsburgh coal. To the present time, the prosperity of the steel industry has depended largely on utilization of this great coal reserve and the cheap transportation afforded by the Monongahela River system. OBJECT AND SCOPE OF INVESTIGATION The initial project in the study of upgrading marginal coking coals was laid out in this area, which contains large reserves of Pittsburgh coal contiguous to the Monongahela and its navigable tributaries. Much of the Pittsburgh coal remaining here is known to have a high sulfur content. The problem of reducing the sulfur to meet metallurgical requirements already has received much attention, and it is considered to be one of the most difficult technologic problems in the field of coal washing.

Jan 1, 1950

By J. M. Stuve

In this Bureau of Mines investigation, the low-temperature heat capacities of polycrystalline phases corresponding to the sulfide compounds CoSO?89' CoS1?33, and CoS2 were measured by adiabatic calorimetry within the nominal temperature range 5 to 300 K. The derived absolute entropies S298 were 10.36±O.02, 12.96±O.03, and 16.31±O.03 cal?mol-1?K-l, respectively, assuming third-law behavior. In addition, the standard enthalpy of formation 8Hf298 of CoSO?89 was determined by bromine solution calorimetry. The derived value of 8Hf298 was -50.63±2.1 kcal?mol-1, based on the 8Hf298 of Co0. This result is considerably more negative than previously published formation values based on high-temperature gas equilibrium studies.

Jan 1, 1985

By H. L. Burmeister

This report describes the mining and milling practices used by the Eastern Magnesia Talc Co. at its Johnson, Vt., operation. The report also contains a description of the local geology and all available information on cost and performance data. Since 1925 the mine has produced continuously at an average annual rate of 54,000 tons, and the ratio of ore hoisted to finished product is roughly 2 to 1. Ore is stoped by a combination of shrinkage and sublevel methods. In any 24-hour period the mill produces an average total of 14 grades of finished talc product, 9 by dry grinding and air classification and 5 by wet grinding and flotation methods. The mine operates one shift per day, 5 days per week and the mill operates on a 3-shift, 5-1/2-day-per-week basis. Operating costs for 1958, on a percentage basis, were mining, 22.34; milling, 54.77; ore haulage, 2.89; and all other, 20.00 percent.

Jan 1, 1963

Research 82 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information, 2401 E Street, NW., Washington, D.C. 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1982

By C. E. Jordan

The Bureau of Mines is conducting research into the pneumatic recovery of coarse mica and has used this method to produce mica concentrates that contain more than 90 percent mica. This research is being carried out pursuant to the Bureau's objective to develop technology that will help maintain an adequate supply of minerals and metals to meet national economic and strategic needs. Researchers used a Bureau-designed system of crushers, screens, and zig-zag air classifiers to concentrate coarse liberated mica particles from mica-bearing materials. This pneumatic system was used to concentrate four mica ores from Arizona, North Carolina, and South Dakota and three waste tailings from Alabama, Georgia, and South Dakota. Using these samples, it was demonstrated that plus 65-mesh size mica can be effectively recovered by the pneumatic method. Not only were the concentrates high in mica content; it was also demonstrated that this method can be used to recover up to 78 percent of the mica that was originally contained in the samples. Because it is a dry concentration method, the pneumatic beneficiation technique may be advantageous in areas where water resources are limited.

Jan 1, 1980

By Thoms L. Chapman

The San Manuel is a deposit of low-grade disseminated copper ore. It was brought to the attention of the government in October 1942 through an application to the Reconstruction Finance Corporation for a development loan, supported by a report by Henry W. Nichols. Nichols’ sampling of two outcrops containing copper silicate and his geologic map indicated that a minable body of copper ore might be developed. The Federal Geological Survey was requested to examine the property. The Survey mapped the geology in March 1943 and cut a few check samples, which substantially confirmed Nichols’ sampling of the outcrops and a few shallow workings. The geologists of the Survey recommended some test drilling by the Bureau of Mines. The property was examined by the author and W. D. Hughes, associate engineer of the Bureau of Mines on March 22 and 26, 1943, and a preliminary drilling campaign was recommended. Five shallow churn-drill holes totaling 1,480 feet were put down under the supervision of Chas. A. Kumke, one of the Bureau’s engineers, from November 23, 1943 to January 15, 1944. This work indicated that the deposit extended deeper than the 350-foot depth attained in the deepest hole and might have very considerable areal extent. Additional funds were allotted, and the drilling contract was extended twice to a final maximum of 17,000 feet with 2,000 foot maximum depth of hole. Drilling was continued by the Bureau of Mines until February 2, 1945, when 15,844 feet of hole had been drilled. The Magma Copper Co. took options on this and adjoining property in September 1944 and commenced drilling with two machines. It also engaged the two contract drills used by the Bureau after it stopped drilling. It exercised its options in August 1945 and organized the San Manuel Copper Corp. to operate the property. That company is continuing to explore the ore body with six churn drills. Thomas Lyon took options early in 1945 on holdings adjoining the San Manuel property on the east and is operating two churn drills. Exploration up to the completion of the last holes started by the Bureau of Mines indicated a block of ore 5,100 feet long, 400 to 800 feet wide, and 500 to 900 feet thick, and averaging about 0.8 percent copper. Subsequent drilling showed that the ore body extends considerably beyond this block. The axis of the ore body strikes about N. 61º E. Copper minerals are disseminated in hydrothermally altered quartz monzonite and monzonite porphyry. Ore outcrops in two small areas over the northeast part of the block. Elsewhere the copper-bearing rocks are capped by Gila conglomerate, which thickens toward the west and south. Drilling showed that the ore is in a thick, tabular body with a steep dip to the south. The ore body lies near the surface in the northeastern part of the block. The south side of the block is much farther below the surface than the north side. There the upper part of the copper-bearing rocks is lightly mineralized, so that the hanging wall of minable ore lies deeper than the base of the conglomerate cap, which thickens southward.

Aug 1, 1947

By H. A. Dierks, H. B. Link

The purpose of this investigation was to develop a practical feeder apparatus to introduce comparatively large pieces of coal and similar material into a pipeline under pressure in connection with the vertical hydraulic transportation of solids , termed " hydraulic hoisting . " This method of hoisting the precrushed run - of - mine product of an underground mine has been given unusually wide attention abroad and could be of considerable significance to the U.S. mining industry in its search for operating improvements and cost reduction . A lock-hopper assembly was developed after a series of sinking velocity tests were made by dropping anthracite in a column of water . The system functioned reliably as an automatically operated feeder apparatus .

Jan 1, 1964

By Hillary W. St. Clair

This report describes a mathematical procedure for analyzing size distribution data by the method of moments. The method was applied to Andreasen's data on a variety of grinding mill products. It was found that the observed size distributions could be represented by gamma and beta distribution functions over a wide range of sizes. A computer program, written in BASIC, is described for calculating moments, distribution parameters, and the weight fraction in any size range.

Jan 1, 1969

By J. Baicker

A two-inch diameter probe containing an intrinsic germanium detector, a canister-type solid cryogen cooling system, cooled FET preamplifier, linear amplifier, high voltage supply, analog-digital converter, microprocessor, buffer memory, bidirectional cable link, and all power supplies has been designed, assembled and tested. A surface support vehicle was designed, built and outfitted. A mini-computer system was constructed and preliminary software developed and tested. A special handling system for a Cf-252 neutron source was designed and has been ordered. The entire system (less the neutron source) is ready for its first field tests. Lab description of the system is presented.

Jan 1, 1978

By R. Barany

Thermodynamic calculations pertaining to the minerals gibbsite, kaolinite, halloysite, and dickite have been hampered by the lack of adequate heat and free energy of formation data. Previous data for gibbsite were highly uncertain, and there were no data for the other three substances. By use of hydrofluoric acid solution calorimetry, the Bureau of Mines derived heat of formation values from the elements and from the oxides for the four substances, and the data were combined with known entropy values to obtain the corresponding free energies of formation. The results show that gibbsite and halloysite are thermodynamically unstable with respect to the oxides (a- alumina, a- quartz, and liquid water) at 298.15° K,, while kaolinite and dickite are only moderately stable (to about the same degree), The instability of halloysite, in comparison with kaolinite and dickite, results in a 60°-lower equilibrium decomposition temperature.

Jan 1, 1961

By W. M. Deaton

The Keyes Helium Plant of the Federal Bureau of Mines was constructed under an expedited schedule, to supply the urgent and growing demand for helium in atomic energy, missiles, aerology, space exploration, shielded-arc welding, and low-temperature research. Construction began in December 1958 and ended in August 1959. The plant, near Keyes, Okla., processes 2 percent helium-bearing natural gas from the Keyes gasfield. In 1960 the plant produced and shipped 263 million cubic feet of helium (equivalent to an annual rate of 290 million cubic feet). Production cost was $9.11 a thousand cubic feet of helium. A low-temperature process involving two steps is used; the first separates a crude-helium product from the natural gas at about -250° F. and 225 pounds per square inch gage (p.s.i.g.); and the second purifies the crude helium to a high-purity product (Grade-A helium, 99.995 percent helium) at about -320° F. and 2,750 p.s.i.g.

Jan 1, 1961

This report summarizes the cost of U.S, mining and milling industry compliance with the Environmental Protection Agency (EPA) interim water quality guidelines for waste discharges. Applicable excerpts from Public Law 92-500 are stated and interpreted in conjunction with the guidelines being used for implementation of the law. Over 200 U.S. Army Corps of Engineers applications for discharge permits were used to develop the quality and quantity data base needed to estimate the cost to comply with EPA guidelines, Cost of three basic treatment methods were considered: Aeration, addition of lime, and sedimentation. From the process design, cost-capacity graphs were developed to consider maximum flow rate, maxi lime addition, and average flow rates. The graphical method used in this evaluation should provide a reasonable guide to the effect of waste treatment and, therefore, Public Law 92-500 and corresponding EPA guidelines on the mineral processing industry. The cost of complying with the EPA guidelines will have the effect of prompting the mining industry to minimize the production of waste water and of undertaking some additional treatment, Two case studies are presented to illustrate efforts that might be fruitful for minimizing waste water production and for treatment of combinations of acid mine drainage, mill wastes, and metallurgical process wastes when treatment is deemed necessary.

Jan 1, 1975

By R. J. Kuczynski

The U.S. Bureau of Mines Reno Research Center investigated, developed, and patented a high-temperature cyanide leaching process for recovering platinum-group metals (PGM) from automobile catalysts. A batch pilot plant was constructed at the center and operated to demonstrate this technology to industry. Approximately 1,600 kg of used pellet, monolith, and metal support catalysts containing 1,700 g (54 tr oz) of PGM was processed. Forty-five-kilogram batches of used catalysts were leached with sodium cyanide solution at 160°C for 1 h in a countercurrent processing sequence. This selectively dissolved the PGM. Average extractions from the used pellet catalyst were 96 pet Pt, 95 pct Pd, and 73 pct Rh. Average extractions from the used monolith catalyst were 84 pct Pt, 81 pct Pd, and 66 pet Rh. Heating the pregnant leach solutions to 275°C for 4 h destroyed the PGM-cyanide complexes, causing over 99.7 pct of the PGM to precipitate from solution. The PGM precipitate was predominantly a metallic powder concentrate, typically analyzing greater than 50 pct PGM. Heating destroyed the cyanide to less than 0.2 mg/L free and total cyanide. Both the pellet and monolith residues were evaluated for disposal using the toxicity characteristic leaching procedure developed by the U.S. Environmental Protection Agency.

Jan 1, 2010

By L. A. Schutz

Personnel of the Bureau of Mines have conducted investigations in the principal asbestos mines and mills in the United States, to determine the concentration of airborne asbestos fibers in the workplace, and to establish the exposure of workers to such fibers. 'The surveys were conducted using the sampling and evaluation method recommended by the National Institute for Occupational Safety and Health. The method consists of collecting the air-borne sample on filters and, after appropriate sample preparation, counting the fibers utilizing phase contrast microscopy. The results of the investigation show that fiber concentrations are low in the asbestos mines but high in the asbestos mills, ranging well above 5 fibers/ml of air based on a count of fibers greater than 5 urn in length.

Jan 1, 1973

By Margaret R. Egan

A study of the combustion emission products of rigid ventilation ducting was completed by the U.S. Bureau of Mines. The ducting was composed of fiberglass-reinforced polyester resin. Four properties of the ducting were evaluated: (1) propensity to ignite, (2) smoke characteristics, (3) gas emissions, and (4) heat release. Particle sizes, obscuration, optical densities, and production constants for gas and smoke were also calculated. These results provide comprehensive data about the emission products, detectability, and relative hazards of fiberglass-reinforced plastic ducting and other mine combustibles under realistic fire conditions.

Jan 1, 1990

By R. E. Heithecker

[The principle of determining volumes of liquid by alternately drawing in and discharging given quantities of the fluid from a confined space or compartment of known volume and mechanically counting the number of displacements is well established. This is true particularly in water measurement. For several years, oil meters employing the same basic principle have beer, used for gaging oil production from individual wells, groups of wells, and in some areas for metering the entire production from a property. Especially in areas where there is town-lot drilling and space for tankage in at a premium, oil meter have been used successfully to gage the oil. This facility has obviated the necessity of installing gage tanks. Oil meters also have been used in pip-line and refinery operations and in loading tankers. Present knowledge of the subject shows that positive-displacement oil meters can be used for measuring crude oil in the field and elsewhere, provided the meter-counter mechanism is in proper adjustment and the oil has been studied sufficiently to determine the proper factor to be applied to the volume as registered by the meter, making possible the adjustment for the shrinkage of the oil caused by liberation of gas from solution.]

Jan 1, 1938

By Y. Miron

'This report presents a U.S. Bureau of Mines study to identify the causes of self-heating events beneath the floor of a deep underground coal mine. Mine samples from both heated and unheated areas were examined by various techniques, including visual, microscopic, thermal, chemical, and instrumental tests. The combined results led to the conclusion that pyrite (FeS2) oxidation was the prime cause of the beatings. However, adiabatic oven tests of selected samples did not indicate the effect of the pyrite on the self-heating process, probably because of the experimental conditions. A fast, simple procedure to assess the concentration of pyrite in the mine samples was developed, g the reactivity of the sample with an aqueous solution of hydrogen peroxide (H2O2).

Jan 1, 2010

By C. E. Armantrout, H. Kato, M. I. Copeland, M. Krug

The investigation of the nickel - gadolinium phase diagram was undertaken to determine the alloying behavior of these two metals . The data from meltingpoint determinations , thermal analyses , metallographic examinations , and X- ray diffraction analyses revealed a phase diagram with three eutectic points and seven intermetallic compounds . Very limited solubility of the phases in each other was observed . The five phases , Ni Gd , Ni , Gd , Ni Gd , Ni, Gd , and NiGd¸ , melted incongruently at about 1,300 ° , 1,270 ° , 1,180 ° , 1,070 ° , and 775 ° C , respectively . Ni Gd and NiGd melted congruently at approximately 1,550 ° and 980 ° C , respectively . Four of the compounds were determined to crystallize in the hexagonal system : Ni Gd , Ni Gd , Ni , Gd , and Ni Gd . Ni Gd was determined to be cubic and NiGd , orthorhombic . The crystal system of NiGd was not determined . The eutectic points occurred at 13 , 67 , and 85 wt pct gadolinium , and the isotherms at 1,290 ° , 890 ° , and 700 ° C , respectively .

Jan 1, 1964

By E. C. Tarpley, R. A. Drogowski, R. F. Abernethy

Three of the test methods frequently used for the determination of moisture in the analysis sample of coal were employed in analyzing a series of coals ranging in rank from anthracite to lignite . For most coals , the variation between the three methods are within the tolerances allowed between duplicate determinations by the same method . The processing variables studied included atmosphere , flow rate of atmosphere , inert atmospheres , oven temperatures , heating time , exposure of the dried coal to laboratory air , and surface area of the test sample . Unless close control is kept on these variables , erratic results will be obtained .

Jan 1, 1964