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By Harold M. Smith

Important discoveries of new oil fields were made in 1937 in the State of Illinois. Oil production, which was virtually constant during 1934, 1935, and 1936 at about 4,400,000 barrels a year, a increased to 7,499,000, barrels during 1937, and in 1938 this production was trebled. In 1939, 94,302,0003/ barrels were produced (almost four times the 1938 quantity), making Illinois one of the cost important oil-producing areas in the United States. The Bureau of Mines has analyzed 35 samples of petroleum from these new Illinois fields and presents the analyses herein. Included with them in this report are analyses of seven samples from fields developed before 1936.

Jan 1, 1940

By R. D. Berkenkotter

This report describes a weighted method for evaluating the mean and variance of assay data from samples of different length . The method , which produces unbiased estimates from which valid confidence limits can be computed , is appropriate for bedded deposits of variable bed thickness and for vein deposits of variable vein width . Assay data from the bedded Florida phosphate deposit is used to illustrate the procedure .

Jan 1, 1964

By G. L. Neumann

"INTRODUCTION Mining in this area is inactive. The entire region is now comprised of small farms. Because approximately 1,500,000 tons of magnetite ore had been shipped from this area between 1855 and 1915, it was deemed probable that geophysical surveying and core drilling might indicate other ore bodies or sizable extensions of the previously mined ore bodies.ACKNOWLEDGEMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has, as its primary objective, the most effective utilization of our mineral resources, thus fortifying our national security and economy. It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative work and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiatien tests.The chemical analyses and beneficiation tests included in this report were performed at the Eastern Experiment Station of the Bureau of Mines at College Park, Md., under the general supervision of J. B. Zadra, chief, College Park Division, Metallurgical Branch, and the immediate direction of Dr. Alton Gabriel, head of the laboratory service unit.The Mineral exploration Was under the general supervision successively of G. D. Jermain, district engineer, C. B. White, district engineer, and McHenry Mosier, chief, College Park Division, Mining Branch.The geophysical section of the exploration was performed by G. B. Botsford, engineer of the Bureau of Mines. Assistance was given by the Division of Geophysical Exploration of the Bureau of Mines, Dr. F. W. Leo, chief."

Dec 1, 1947

By G. L. Neumann

"INTRODUCTION AND SUMMARYThe Guymard mine in Orange County, N. Y., is reported to have been discovered in 1862 and mined until 1876, producing 10,000 tons of lead and zinc ore. 2/The property was examined by an engineer of the Bureau of Mines 3/ in 1948. Development work was done by the Bureau in April and May 1949 and March 1950. During these two periods four drill holes totaling 2,090 feet were completed. The mineralized sections of the core were sampled and assayed.ACKNOWLEDGMENTSThe diamond drilling was conducted under the general supervision of McHenry Mosier, chief, Mining Development Branch, Minerals Technology Division, Region VIII, and the direct supervision of Kenneth M. Earl and the writer as project engineers. Drill cores were logged by Paul K. Sims of the Federal Geological Survey. Chemical analyses were made by the Bruce Williams laboratories, Joplin, Mo., and the Minerals Processing Branch, Minerals Technology Division, Region VIII, Bureau of Mines, under the general supervision of Paul M. Ambrose, chief, and the direct supervision of Howard F. Carl, chief, Physical and Chemical Section.LOCATION AND ACCESSIBILITYThe Guymard deposit (see fig. 1) is on the west slope of Mount Hope, Orange County, N. Y., 1,500 feet northeast of Lake Guymard.Graham station, near the deposit, is on the Erie Railroad about 8 miles north of Port Jervis and 4 miles south of Otisville."

Aug 1, 1952

By G. L. Neumann

The Guymard mine in Orange County, N. Y., is reported to have been discovered in 1862 and mined until 1876, producing 10,000 tons of lead and zinc ore. The property was examined by an engineer of the Bureau of Mines in 1948. Development work was done by the Bureau in April and May 1949 and March 1950. During these two periods four drill holes totaling 2,090 feet were completed. The mineralized sections of the core were sampled and assayed.

Jan 1, 1952

By A. W. Deurbrouck

Five preparation plants employing concentrating tables for washing 3/8- inch to 0 raw coal were tested. Two of the plants were washing Pittsburgh-bed coal, two were washing Pocahontas-bed coal, and one was washing Elkhorn-bed coal. Samples of the feed to and products from the tables were collected over the normal operating shift. These samples were analyzed, and complete performance criteria were determined. The results of this study show that the concentrating table is an effective fine-coal cleaner even when operating at 40 percent over the recommended 10 tons per hour feed rate. Recovery efficiencies for the 3/8-inch to 200- mesh size fraction ranged from 97.3 to 99.3 percent; maximum yield errors and ash errors were 2.4 and 1.0 percent, respectively; probable errors ranged from 0.074 to 0.115 specific gravity units and error areas from 52 to 73 square centimeters. The amount of minus 200-mesh material in the water used for feed water and dressing water to the table had no significant effect on the sharpness of the separation achieved but did have an effect on the ash content of the clean- coal product. In the one plant studied, the substitution of fresh water for plant circulating water reduced the ash content of the clean coal by about 6 percentage points.

Jan 1, 1963

By G. M. Potter, S. J. Hussey, R. Havens

The Artillery Peak manganese ores , from one of the largest known manganese deposits in the United States , present a difficult problem in concentration because they are low-grade and the association of manganese and gangue minerals is intimate and complex. The known size of this deposit has justified investigation of processes such as leaching, wherein preliminary enrichment of the original feed might be advantageous .. Therefore , the ore-dressing studies on Artillery Peak ores were carried on with the object not only of making directly marketable manganese products but also of removing acid-consuming calcite and raising the grade of ore for leachingplant feed . Owing to the extent of the deposits , test work was carried on at the Salt Lake laboratories in considerable detail on several lots of ore of varying composition . This paper summarizes the results obtained from laboratory testing of four samples obtained by engineers of the Mining Branch from the Maggie Canyon area of the Artillery Peak deposit . Also included are results obtained from testing one sample of Chapin Group ore , which was considered representative of numerous very low-grade ores submitted from the Artillery Peak district . During the course of the investigations , many data were obtained and compiled , but for the sake of brevity , data of secondary importance have been omitted or condensed and only those tests giving the more pertinent results are discussed in detail ...

Nov 1, 1947

By Suresh K. Bhatt

This U.S. Bureau of Mines report reviews major developments in continuous haulage technology for underground coal mines. Haulage systems, both in use and under development, were investigated through a comprehensive literature search and visits to mines and manufacturers. The systems include flexible conveyor train, mobile conveyor, monorail bridge conveyor, multiple-unit continuous haulage, extensible, and belt turning systems. Strengths and weaknesses of the systems are assessed in light of their operating under remote control and their application to the computer-assisted continuous mining machine research being conducted by the Bureau. Through mining scenarios, candidate haulage systems are conceptualized to be consistent with the capabilities of the mining machine.

Jan 1, 1991

During 1990-1999, a total of 458 fires occurred in all coal mining categories; 157 of those fires caused 164 injuries and 2 fatalities. The greatest number of fues and fire injuries occurred at surface mines, whch also had the highest risk rate values. A total of 66 fuefighting interventions were required. Of these, there were 25 mine rescue team interventions in underground mines, including 5 mobile equipment firefighting interventions, and 41 fire brigade and fire department interventions at all surface operations, including 19 mobile equipment interventions. In all, 50 fires destroyed or heavily damaged equipment (including 16 pieces of mobile equipment) because of failure of other firefighting methods, late fire detection, undetected fires, or fire size. A total of 1 14 fires were detected late by smoke, and 42 fires were not detected.

By Thomas Fraser

About 24 per cent of our total production of bituminous coal is used in industrial power plants. As regards fuel conservation, therefore, the recovery of unburned fuel from furnace refuse presents interesting possibilities. Considerable attention has been given to this problem in the past, but because of the comparatively low initial cost of power plant fuel in the pre-war period little progress, has been made in this direction in the United States. Because of the higher price of coal in Europe more attention has there been given to the problem. In Germany a process has been developed for separating unburned coal in refuse by using an electromagnetic separator In the United States the use of mechanical stokers enabled low-priced screenings of high ash content to be used, so that even with relatively high percentages of combustible material remaining in the refuse, the loss in money is not excessive. If the price of screenings returns to the pre-war level around $1.00 per ton the process proposed here will probably not be especially interesting, except where the freight charges are very high. However, if the price of delivered coal continues high, such a process should result in considerable saving. The cost of continuous operation of such a refuse treating plant should not exceed 75 cents per ton of fuel recovered.

Jan 1, 1921

By Timothy Y. Yen

This Bureau of Mines report evaluates audio dosimeters, 3 sample units from each of 10 currently marketed brands. Each dosimeter was treated as a "black box" with the acoustic stimulus as the input and the accumulated dosage as the output. The dosimeter microphones were exposed to a sound field gener¬ated in an anechoic chamber. Characteristics evaluated include frequency response (100 to 8,000 Hz), level-time trade-off rate (88 to 117 db), status of calibration, crest-handling capability, and power consumption rate. Experi¬mental errors revealed by replication of the tests were found to be generally much smaller than variations in performance among the samples of any brand, and possibilities of further reducing the magnitude of these errors are discussed.

Jan 1, 1977

By E. D. Gardner

During the summer of 1935 a plan was proposed by which the Government should establish custom sampling plants for gold and silver ores in the mining districts of the West, where the construction of such plants would be justified as an unemployment relief measure. It was known that in many districts prospectors and small operators had small lots of smelting ore that could not be marketed for lack of sufficient capital to get out enough ore at a time to make carload shipments to distant smelters. Moreover, considerable ore of milling grade was available in many districts in which there were no custom milling facilities. It was felt that. accurate sampling and the classification and consolidation of small lots of ore produced from prospects and small mines, with quick cash returns to the shippers on a nonprofit basis, would stimulate the working of small gold and silver properties: Idle mines would be put to work, and there was a possibility that some of the prospects could be developed into regularly producing mines. Each sampling plant was to be centrally located so as to serve the greatest possible number of mines and prospects. Wherever possible, the plants were to be built on a railroad, is ore of smelting grade accumulated, it was to be shipped to a smelter in carload lots. Where a plant was not on a railroad, smelting ore was to be trucked to the railroad after being sampled.

Jan 1, 1936

By G. A. Smyres

The Bureau of Mines conducted laboratory studies to determine the feasibility of chlorine-oxygen leaching for treating low-grade zinc sul-fide flotation concentrates. Recovery of zinc sulfides by flotation from complex fine-grained sulfide ores is substantially higher in low-grade bulk sulfide concentrates than in the high-grade cleaned concen-trates required for smelter feed. However, there is no commercial process in the United States for the treatment of low-grade bulk zinc sul-fide concentrates. Leaching experiments using reactors of 500-mL and I-gal capacity were conducted on a bulk concentrate containing 19.3 pct Zn, 35.6 pct Fe, and 39.4 pct S. The effects of pressure, temperature, and percent solids on extraction were investigated. The chlorine-oxygen leaching procedure showed promise for treating the concentrates. Zinc extractions of 95 pct or more were obtained by leaching at 50 pct solids in the temperature range of 1000 to 1200 C. Zinc extractions by leaching with chlorine followed by oxygen at reactor pressures of 50 to 100 psig were independent of pressure.

Jan 1, 1985

By James P. Bennett

The Bureau of Mines investigated the role of imported natural flake graphite in dolomite-carbon refractories used in steelmaking processes. Fundamental engineering data were obtained to enable the evaluation of substitute materials. Changes in oxidation resistance (2,000° F), hot strength (2,750° F), and deformation under load (2,7500 F) caused by 10-wt-pct additions of five different kinds of natural flake graphite and increasing quantities (0 to 30 pct) of a 90-pct-carbon natural flake graphite were studied. Results indicated that carbon purity of 10-wt-pct-graphite additions did not influence hot strength or deformation under load. When the quantity of 90-pct-carbon graphite addition varied between 0 and 30 wt pct in a dolomite-carbon brick, hot strength was highest and de-formation under load lowest with 10-wt-pct additions. As hot strength test temperature was increased from 5000 to 2,750° F, the strength difference observed between 0-and 30-wt-pct additions of a 90-pct-carbon graphite became smaller. Additions of a boron-treated graphite caused significantly higher strength and lower deformation under load at high temperatures, while an addition of ball clay significantly reduced strength and increased deformation.

Jan 1, 1987

By Willard J. Tesch

The borehole surveying system described is used to measure ground movement over and near operating mines. The magnitude of any movement is con-trolled by the ground conditions, the mining method, and the mine progress. By correlating these factors with the measured movement, equations can be determined for predicting the effect of mine progress on the surrounding ground. These equations can also be used to predict the effect of mining a similar deposit with similar ground conditions. The borehole surveying system is used in cased boreholes to measure the inclination of the hole in two perpendicular planes. Grooved casing with an inside diameter of 3 inches is grouted in the hole. Two probes are used to obtain the data necessary to calculate the hole position versus depth. One of the probes contains a gyroscope, and the other contains a biaxial force-balance [s]ervoaccelerometer. Readings from the transducers in the probe are punched on paper tape by an automatic data acquisition system as the probe is pulled up the hole at 30 feet per minute by an electric winch. Readings from the inclinometer probe containing the accelerometer are used as input data to an on-line programmable calculator as they are punched on tape. The calculator computes preliminary results of the survey being made. The paper tapes obtained during the survey runs are later used as input to a computer that computes the offsets of the drill hole versus depth in true north-south and east-west planes. These offsets are printed for each foot of depth. Changes in these offsets between the first survey and subsequent surveys are a measure of the horizontal ground movement between the surveys.

Jan 1, 1976

By Raghoottma S. Pandurangi, Mohindar S. Seehra, Pedro Bolsait, Bronwyn L. Razzaboni

"Surface IR (infrared) modes of crystalline and fumed (amorphous) silica particles, calcined at temperatures up to 1095°C, have been studied by Fourier transform infrared spectroscopy. The ability of these same particles to lyse cells has been measured by a hemolysis protocol. The untreated crystalline and amorphous materials differ by a factor of 40 in specific surface area, and the intensity per unit mass of the sharp surface silanol band near 3745 cm-1 in the amorphous material is an order of magnitude larger than in the crystalline material. A similar difference is observed in the lysing potential of the two materials. The intensity of the silanol band increases after calcination for both materials, reaching peak values near 500°C, followed by a dramatic drop at higher calcination temperatures, and reaching negligible values for materials calcined near 1100°C. The lysing potential data follow essentially the same pattern for both crystalline and fumed silica. These results are consistent with the hypothesis that the surface silanol groups are involved in cell lysis. Further experiments are suggested to evaluate the relationship between the surface structure of ailica particles and their potential cytotoxicity. IntroductionThe characterization of the surface structure of various allotropic forms of silica is of interest because the cytotoxicity of silica particles of respirable size has been commonly related to the chemical interaction of functional groups on the surface of such particles with the lipoproteins contained in cell membranes (1-3). It has been found that the cytotoxic potential of silica particles varies greatly with their crystalline structure (4,5), particle size (6-8), surface composition (9), and molecular surface configuration (1,10). Studies of the infrared (IR) modes of various forms of silica have been reported by a number of researchers (3 ,11-19). Several books and reviews (20-24) have dealt with the identification of functional groups on silica surfaces and the effect of heat treatment on the surface structure. The nature of the surface is said to be critical in determining the biological activity of silica dusts (3).Fourier transform infrared (FTIR) spectroscopy is a highly sensitive ·technique for identifying IR surface modes of tine particulates, and it was deemed of interest to examine the surface structure and its relation to lysing potential of two widely different types of respirable silica dust. The lysing potential of respirable dust particles has been considered a first-level test for potential cytotoxicity."

Jan 1, 1990

By W. M. Dressel

The Federal Bureau of Mines has obtained data by differential thermal analysis of the various minerals that represent the nation's resources in manganese. These data are supported by X-ray diffraction analysis, chemical analysis, mineralography, and optical mineralogy, and provide fundamental information on the response of each mineral to thermal treatment in oxidizing, reducing, and neutral atmospheres. The information can be applied advantage¬ously in the identification of manganese minerals. Its greatest potential value, however, lies in the application of the quantitative data on the reaction temperatures, rates, and products to the more efficient extraction of manganese from U.S. ores. Thermal analysis curves are presented for certain manganese minerals, namely hausmannite, bixbyite, braunite, pyrolusite, lithiophorite, cryptomelane, hollandite, manganite, rhodochrosite, and rhodonite. The original minerals and the products of their thermal decomposition were identified by X-ray diffraction analysis, supplemented by chemical analysis and mineralogical identification.

Jan 1, 1961

By James P. May

Operating mine haulage trucks near the crest of stockpiles and waste dumps is a potentially hazardous practice often resulting in a localized slope failure and a dump point accident. The U.S. Bureau of Mines has developed a computer code (INSLOPE3) based on the kinematic method of limit analysis which determines an admissible truck weight (upper bound value) for varying distances from the slope edge. The program considers the material strength parameters, slope geometry, and inertial forces induced by vehicle braking. The program can be utilized to assist in the determination of safe operating distances for a haulage truck from a slope edge, the development of safe vehicle operating procedures, and the admissible weight for a static concentrated loading near the crest of an otherwise stable slope. This report provides information on the use of INSLOPE3, interpretation of the results for mining applications, and instructions for acquiring a copy of the software.

Jan 1, 1991

By McElroy. G. E.

"INTRODUCTION The ventilation of development faces in mines for diluting gas or dust concentrations and, in hot mines for providing air-motion cooling effect, by fan pipe units discharging high-velocity streams of air close to the face, is an important phase of mine ventilation. The effectiveness of such units depends largely on the air-flow distribution between the pipe discharge and the face, a subject on which little definite information is available. A study of the air flow from grills into rooms 3/ has provided some basic data, but under conditions no different from mine fan-pipe installations in development ends that the data are of doubtful application to mine installations, owing to differences in air-flow conditions.The purpose of this report is to present and discuss the results of an initial series of tests of a general investigation designed to yield definite laws and design data for the discharge of fan-pipe lines in mines. This series was planned to yield preliminary data on the effects of velocity of discharge, size and shape of pipe, and adjacent walls on the air-flow distribution. Tents were made on 10-inch pine with seven different end conditions and one change of wall condition. Changes in size and shape of discharge wore made by short transformation pieces directly at the discharge end, with the result that effects due to contraction and expansion of the flow, which proved to be of much greater importance than was expected, totally obscured any normal effects due to size and shape. The results of this series of tests, therefore, relate to 10-inch pipe with various discharge designs and are so reported."

Aug 1, 1940

By Walter Kawa

Bureau of Mines research on the hydrogenation of coal has been concerned with developing processes that could be used to supplement the Nation's petroleum and natural gas resources. Motor fuel was produced in a subsidized coal hydrogenation industry in Europe prior to 1945, but the process used is still not economical and other methods of producing liquid and gaseous fuels from coal are being investigated. As an aid to the planning of coal hydrogenation research, a literature survey was made of processes or methods of hydrogenating coal that differ from the subsidized or conventional process. This report contains a bibliography of unconventional methods of hydrogenating coal and a brief discussion of the economics of the conventional method. A general discussion of unconventional methods is included, and the advantages and disadvantages are pointed out where possible. The survey supplements a previous Bureau of Mines survey3 and a comprehensive review published in 1930.4

Jan 1, 1964