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By James F. Neill, O&apos

Investigation of the Gilley fluorite deposit was based upon examinations made by several of the Bureau's mining engineers. Fluorspar was found in the dump talus of sloughed and water-filled trenches and shafts, and there were indications that faulting or other dynamic distortions favorable to deposition of this mineral in minable quality and quantity might exist. The inference was based upon a field study of the area and its comparison with fluorspar deposits in Kentucky. The proximity of this deposit to the iron furnaces at Gadsden and Birmingham was a factor that influenced its investigation, as the demand for metallurgical grades of this critical mineral is acute. The present supply for the district is obtained from out-of-State sources, and the value of any local deposit would be enhanced by the saving in freight charges. The Gilley fluorspar deposit is 17 miles east of Gadsden and 50 miles northeast of Birmingham, Ala. Mineral deposits occur as thin veinlets and small bunches of fluorite in upturned bode of siliceous limestone. The ore-bearing structure is a reverse fold, and the mineral deposit appears as a replacement along crumbled zone fractures of the contorted limestone.

Jan 1, 1950

By Wilbert J. Huff

The Explosives Division of the United States Bureau of Mines makes certain laboratory and field investigations that deal with explosions, explosives, ignition, and combustion, together with many related problems, such as the cause and prevention of fires, and certain fundamental scientific questions bearing upon the determination of the chemical and physical mechanisms underlying some of the important phenomena encountered. Its work on explosives has been particularly directed toward determination of the chemical and physical characteristics of explosives designed for use in coal mines and in a more limited way to those used in metal mines, tunnels, quarries, and other engineering operations. This testing is handled by two units of the Explosives Division, as follows:

Jan 1, 1937

By K. O. Bennington

Cancrinite is one eonstituentof "red muds," a high-volume waste product of alumina production by the Bayer process. The Bureau of Mines determined the thermochemical properties of cancrinite as part of a program to provide such data for minerals of industrial importance. Cancrinite [Na7.68(A16Si6024)(N03)1.68 (H2O)4.1] was synthesized by reacting aluminum silicate gel with a solution of NaOH and NaN03, and the composition was determined by chemical analysis, differential scanning calorimetry, and thermogravimetric analysis. The heat of solution was determined by hydrofluoric acid solution calorimetry. The standard enthalpy of formation at 298.15 K, ?Hf°298, is ?Hf°298 = -3,487.97 ±2.6 kcal/mol, and the standard enthalpy of formation from the oxides and NaN03, ?H°298, is ?H°298 = -215.20 ±l.8 kcal/mol.

Jan 1, 1983

By B. R. Mohal, F. F. Aplan, S. Chander

"ABSTRACTThe wetting behavior of coal has been determined in the presence of nonyl and octyl series of nonionic surfactants containing polyethoxy groups of different sizes. The wetting behavior was determined by a modified Walker technique and contact angle measurements. The results show that the wetting rate of coal varies with coal rank, structure of the hydrocarbon chain and number of ethoxy groups in the hydrophilic group of the surfactant. A close relationship has been observed between the wetting rates and the short-time advancing contact angles.INTRODUCTIONNonionic surfactants are used in many applications to improve wettability of solids. They can be used as dispersing agents [ 1 ] or dust suppressants [ 2-5 ] and to control the flotation, flocculation, filtration and flowability of particulates. This study was undertaken to study the effect of a series of nonionic surfactants on the wetting behavior of coal. Two series of surfactants, namely, ethoxylated nonyl and octyl phenols were used. The nonyl phenol series contains a linear hydrocarbon chain containing nine carbon atoms ( CH3( CH2 )8-C6H4,- ( OC2H, ) n, where n is the number of ethoxy groups) . The octyl phenol series contains a branched hydrocarbon chain containing eight carbon atoms ( ( CH3 ) 3CCH2C ( CH3)2-C6H4- ( OC2H4) n ).Initial wetting rates — modified Walker techniqueWalker et al. [ 6 ] developed a sink test to determine the wettability of coal particles. In this technique, coal particles are dropped individually onto the surface of surfactant solutions of different concentrations, and the most dilute concentration in which coal would sink ""instantaneously"" is determined. This technique is a variation of a procedure initially developed by Draves and Clarkson [ 7 to determine the effect of surfactants on wettability of cotton fibers. In this procedure commonly known as the Draves test, the concentration of a surfactant required to give a 'sink time' of 25 s is determined.Other investigators have used slight variations of the Walker method to study the wetting of fine particles [ 8-12 ] , by measuring the time for wetting a given amount of powder. There are differences in the manner in which the time of wetting is measured, however. Some investigators measure the time for the last trace of coal to disappear [ 8,11 ] whereas others determine the time for the vast majority of particles to sink [ 10 ] . Some investigators report a wetting rate [ 11 ] which is a value calculated on the basis of the time for the 'last traces of particles to sink'. The differences in choice of criterion for wetting can result in different values for wetting rates as illustrated in Fig. 1 which is based upon our measurements of the amount of powder wetted as a function of time. The procedure for wetting rate measurements is described in the next section. The technique in which time for disappearance of the 'last traces of particles' is determined gives the smallest value for the wetting rate, while the technique in which the time for wetting of the 'vast majority' of particles is determined will give intermediate rates. The terms 'last traces of particles' and 'vast majority of particles' are usually not defined explicitly and can lead to large differences in wetting rates measured by different investigators. Since our measurements show that the wetting rates for an assembly of powder decreases with time, we have used the initial wetting rates to compare the wetting behavior of coal in solutions of different surfactants."

Mar 1, 1989

By John B. Umhau

[This !m-i~!.al survey giver, statistice.1 data res;?~dirf ~:rimay ard ?eco~- dqr or scmn tin used in thL: United St,ztas by industries an? incluclcz d;ta on stop&apos;ics, ~urchares, ard plnrt losr.c.5. It is :i ml:anwe of consq~tion in terms of fir.is1icd -prcd.~cts nz6.e iry initid ti11 Sabric:,.torc,, that is, aon- cerns that purchzse virc,in zni s~col~d&apos;l~y i.i.5 ti:; 01&apos; tin c;cra.. rav materi,als ar,d co:lrrert them into !ror?ucts such F!: ti:i plz.te, ~lloyr;, and. c?hemic?ls; comy~nias ;~urchn.&apos;.ii~; alloys, ch:rr.ic,~l::, or tin vl?.tc fcr furthcr a:mflzc- ture ?rc: ~-.f>t i~ci~~dcd. Tilit r~lqe:;tionrr::ire submit tod to consunern ar,nt:incd no dofinition of rnr.oncl.:ryr me$.-i; but, ovrirq to ti~i-: a~counti~ procedure used s.l~o~c-:t 1&apos; thu scrnn hac i~-.rtergol:e ch?rri?~ of ovinerzhip or titlo, thc rc!coverod t! n !its b~en i-c<;,r(it.!rj L.S r,e~3r;d:q met.1. Tbv tin content ~f ]

Jan 1, 1938

By William S. Roberts

As part of the Bureau of Mines critical and strategic minerals program in Alaska, 34 high-purity chromian spinel samples were analyzed for trace and major element geochemistry and mineralogy. The samples were analyzed by X-ray diffraction, X-ray fluorescence, and chemical techniques. Systematic differences in chemistry are evident when samples collected from the Chugach Mountains and their related extension are compared with chromian spinel samples collected from interior Alaska. Compared with the Chugach samples, the interior Alaska samples have higher average amounts of A1203, Fe203, Ti02, and NiO, have lower average amounts of FeO and Cr203, and exhibit greater dispersion in values. Considerable mineralogical variability of chromian spinel exists between and within individual Alaskan chromite-bearing ultramafic complexes. Of 34 samples analyzed, 25 samples are magnesiochromite, 5 are chromite, 3 are spinel, and 1 is hercynite. As a group the interior Alaska samples have a smaller average unit cell dimension than the Chugach group of samples. The chemical and mineralogical differences between the two groups of samples can be attributed to different genetic histories and may have implications for locating chromian spinel deposits amenable to standard beneficiating techniques.

Jan 1, 1985

By G. L. Neumann

The Andover-Sulphur Hill iron mines in Sussex County, N. J., have a production record extending over 100 years. The last production recorded was about 1880. These mines produced high-grade ore of two types: Bed ore (hematite) and blue ore (magnetite. Some sulfides (lead, zinc, and copper) were found underlying the iron deposits. Data as to size and grade of these sulfide bodies are very sketchy, Toward. J. Hewitt of Elizabeth, N. J., lessee of the Sulphur Hill mines from 194045, prospected for lead, zinc, and copper. .His Only production was several hundred tons of low-grade iron ore, which was crushed and used as heavy aggregate to make concrete blocks for ship ballast. In October and November 1942 made a magnetic survey of this area and bored six-diamond-drill holes with the dual objective of prospecting for sulfides and testing for extensions of the iron-ore deposits indicated by the magnetic survey. In 1944, an iron-mining company examined this property and diamond-drilled seven holes Between December 1949 and March 1950, the Bureau Of Mines in search of sulfide deposits, bored three additional diamond-drill holes. Two of these were on the Sulphur Hill tract and one on the adjoining Tar Hill tract.

Jan 1, 1952

By E. M. Frost

"Helium has great value to the oil and as industry as a tracer gas, according to tests just completed in the Elk Hills Field, Naval Petroleum Reserve No. 1, Kearn County, California. When used as .a tracer gas, small percentages of helium are mixed with natural gas pumped into a reservoir for conservation, repressuring, or cycling purposes. Because minute quantities of helium added to natural gases can be detected by analytical methods and accurately determined, the variations of the helium content of gas withdrawn from various parts of a field when helium has been added to the injected gas give interesting and long-sought data on the movement of injected gas through reservoirs.The Bureau of Mines engineers began their studies of the use of helium as a tracer material in gas-injection operations in the Elk Hills, California, oil field, Naval Petroleum Reserve No. 1, in response to a request by the Navy Department for assistance in connection with an expanded oil-production program instituted in that field. This report discusses the Bureau's work on the problem of determining the direction and extent of migration of injected gas in the Elk Hills reservoir by the use of helium as a tracer gas,The Bureau appreciates the cooperation and assistance of Commodore W. G. Greenman, U.S.N., director, and Commander R. Walling, U.S.N.R., Assistant director, Naval Petroleum .and Oil Shale Reserves, Washington, D. C., Captain H. P. Stolz, U.S.N.R., commanding officer, and Commander F. G. Taves, U.S.N.R.., of the Navy's Elk Hills staff. The Bureau also appreciates the cooperation and assistance given by V. O. Wankowski, F. C. Tratt, Marray Putnam, Dana Champion, and other personnel of the Standard Oil Co., of California, operators of the Elk Hills field.R. A, Cattell, chief, and C. C. Anderson, assistant chief, Petroleum and Natural Gas Division; C. W. Seibel, supervising engineer, Bureau of Mines Helium Plants; and H. H. Hinson, petroleum engineer - all of the Bureau's staff - furnished valuable advice and assistance during the course of the work. H. C. Miller and G. B. Shea of the Bureau's San Francisco Office contributed valuable liaison work. The writer wishes to express appreciation to all these people for their cooperation and assistance."

Jun 1, 1946

By W. W. Adams

"The National Safety Competition of 1930, the seventh annual contest conducted by the United States Bureau of Mines to promote safety in the mines and quarries of the United States, has been concluded, and the five winners of the bronze trophies, The Sentinels of Safety,' which are provided by the Explosives Engineer magazine and awarded annually for the most excellent safety records, have been determined by the committee of award. One trophy was awarded to an anthracite mine in Pennsylvania, one to a bituminous coal mine in the same State, one to an iron-ore mine in Michigan one to a gypsum mine in Ohio, and one to an iron-ore opencut mine in Michigan.These trophies were awarded to the companies for having the smallest loss of time from accidents in proportion to the total number of man-hours worked by all employees at their mine or quarry. Honorable mention was awarded to each mine or quarry that ranked second, third, fourth, or fifth in its own ground and to all plants that were operated without a lost-time accident during the contest year. Eighty-four out of 337 plants that competed for the trophies were operated without an accident that disabled an employee beyond the day on which the accident occurred.Under the contest rules, all mines and quarries were divided into five groups, four of the groups representing different classes of underground mining operations (anthracite, bituminous coal, metallic ore, and nonmetallic mineral), and the fifth group repre-senting the quarrying or opencut mining of minerals whether metallic or nonmetallic. Twenty-seven mines were included in the anthracite group, 68 in the bituminous group, 52 in the metal group, 24 in the nonmetallic-mine group, and 166 in the quarry and opencut-mine group. The total of 337 mines and quarries was 26 more than the number of plants that completed the contest during the previous year.The committee of award which determined the winners of the contest was composed of seven members, all known throughout the mineral industry but not connected with the United States Bureau of Mines. The committee included W. H. Cameron, managing director of the National Safety Council; William Green, president of the American Federation of Labor; James F. Callbreath, Secretary of the American Mining Congress; T. T. Read, Vinton professor of mining of Columbia University and editor of Mining and Metallurgy; C. B. Huntress, executive secretary of the National Coal Association; A. J. Curtis, assistant to the general manager of the Portland Cement Association; A. T. Goldbeck, director of the bureau of engineering of the National Crushed Stone Association."

Jun 1, 1931

By E. T. Bowers

The Accident Analysis (ADA) computer program was developed at the Spokane Research Center (SRC) to provide a rapid broad-based analysis of mining accidents. Because the Bureau of Mines often needs this type of information for the development of viable research programs the ADA program was written to access and analyze accident data available frog the Labor Department&apos;s Mine Safety and Health Administration (MSHA). This report describes the ADA program, the data it uses, and the potential value it has for planning mining research.

Jan 1, 1987

By Robert Lee Stahl

Comprehensive field tests were made by the Bureau of Mines at the Schwartzwalder mine near Golden, Colo., to determine whether surface geophysical techniques could be used to detect and delineate faults in uranium deposits. The tests included seismic refraction, magnetometer, electrical resistivity, airborne infrared thermal scanning, and airborne photography. Of the several geophysical techniques tested in the field, horizontal resistivity profiling with electrode spacings in the range of 10 to 15 feet was most diagnostic of faults. The method is quick, inexpensive, and accurate and can be easily used by mining company personnel to detect and delineate faults.

Jan 1, 1974

By William L. Crentz

In the past, Westmoreland County together with Fayette County produced about one-third of the bituminous coal mined in Pennsylvania. The Pittsburgh bed in Westmoreland County has furnished enormous quantities of coal to the by-product and beehive ovens, gas-manufacturing plants, and general industrial manufacturers over a wide area until about 20 years ago. Little attention was paid to the thinner beds because of the superior quality of the Pittsburgh. The approaching exhaustion of Pittsburgh coal will require accelerated-exploitation of these coals if Westmoreland County is to continue as an important source of bituminous coal, Much of the Pittsburgh coal in Westmoreland County is low-sulfur and requires no mechanical cleaning for the preparation of a metallurgical fuel. Even those areas where the sulfur percentage increased to a maximum of about 2 percent, a relatively easy washing operation usually produced a cleaned coal, which found ready acceptance by the coke industry. Davis reported the remaining recoverable reserves of the .Pittsburgh bed in Westmoreland County to be 255,439,000 tons as of January 1, 1937. Since that date, more than 100,000,000 tons of Pittsburgh coal has been extracted so that the time is not too distant when this important coal bed will be depleted. A study of the Pittsburgh bed in Westmoreland -County has not been made a part of this report as the remaining reserves of the coal can be used in coke making with a, minimum of preparation. The production from the Upper &apos;Freeport bed will increase as the supply of coal from the Pittsburgh bed diminishes, and as of the present time it supplies a substantial proportion of the county&apos;s coal output.

Jan 1, 1951

By Doris M. Hyde

The Bahama&apos;s petroleum-dominated minerals sector constricted again in 1985. The declines were mostly the result of a soft market demand for crude oil and petroleum products. In early 1984, it was a growing unprofitability that prompted Charter Oil Co. to cease using the 350,000-barrel-per-day Bahamas Oil Refining Co. facility that it jointly owns with Chevron Oil Bahamas Ltd. After midyear 1985, because of poor petroleum economics, Chevron announced it would close the refinery, leaving only a maintenance crew. In 1984, the refinery exported less than 26 million barrels of petroleum products. Chevron&apos;s throughput was reported as averaging about 8,000 barrels per day at the time of the announcement. The crude oil transshipment terminal also registered declining activity and financial losses in 1984 and 1985. Transshipments of petroleum in 1985 amounted to about 100,000 barrels per day, one-half as much as in 1982.

Jan 1, 1987

The following is a Maintainability Design Checklist for coal mining equipment. The purpose of the checklist is to provide a summary of design review points for the maintainability assessment of new or existing underground equipment. It specifically focuses on the identification of equipment design features, tasks, or procedures that impact equipment downtime, repair costs, labor hours and maintainer skill level requirements. Some checklist points are general in nature. The checklist was designed to be used across all categories of underground equipment. The intent is to draw attention to design features and maintenance procedures that will increase maintainability requirements. You are encouraged to adapt this checklist to site specific or machine specific requirements by: Inserting specific performance criteria for various categories of maintenance tasks. For example; all hydraulic lines on a shuttle car should be replaceable in 15 minutes or 25 minutes, etc. Adding or deleting checklist items for different categories of equipment. You would include environmental control equipment, for example, on face equipment and not on shuttle cars or man trips. Adding additional checklist items based on site or equipment specific maintenance histories or experience, company maintenance standards, or other factors.

Jan 1, 2000

By Wilbur I. Duvall, Thomas C. Atchison, Joseph M. Pugliese

Short cylindrical charges were detonated in drill holes in rock to determine the effect that decoupling ( defined as the ratio of the radius of the hole to the radius of the charge ) has on the strain - generating abilities of explosions in rock . The amplitude and period of the strain pulses produced in the rock were studied as a function of distance , size of charge , and decoupling . The main results of these studies were that , for a given distance and size of charge , the amplitude of the strain pulse decreases as decoupling increases and the period of the strain pulse decreases at first and then increases as decoupling increases . A simplified theory of decoupling is presented that satisfactorily explains the experimental results . The information presented makes it possible to predict the effect of decoupling on explosiongenerated strain pulses in rock and thus helps the explosives user evaluate the effect of decoupling on his blasting .

Jan 1, 1964

By W. H. Oppelt

Converting small-particle lignite to a stable, storable fuel of relatively high heating value was investigated. The fuel was prepared by thermal pretreatment of the lignite in an 8-inch i. d. rotary-drum retort, then the pretreated material was pelletized in an experimental 15-inch-i. d. rotary-drum pelletizer. Pelletizing tests were made with both starch and bituminous binders. During the first phase of the project, the quantity, composition, and heating value of products from the thermal processing of Kincaid lignite from Burke County, N. Dak., in an B-inch i. d. rotary-drum retort were investigated at a series of temperatures from 250° to 950° F. to establish optimum conditions for preparing feed material for pelletizing. To determine the response to thermal treatment of different lignites, 5 other lignites from Divide, McLean, Mercer, and Stark Counties, N. Dak., and 1 lignite from Saskatchewan, Canada, were processed at 700° F.

Jan 1, 1958

By Webster S. Anderson

The design, development, and testing of hydraulic props to provide a lightweight, high strength, recoverable unit is described. Modifications in design incorporating threaded components resulted in the development of a lightweight hydraulic prop fabricated from aluminum alloy tubing. This new design facilitates interchange and replacement of component parts, and the physical properties of the material are not changed as they are when welding is required. The new prop is 65,000 pounds and has a maximum load capacity of a lower weight-to-load capacity ratio than the hydraulic props now available.

Jan 1, 1967

By B. J. Scheiner

Electrooxidation of cinnabar mercury ores (HgS) was investigated as a means of providing an effective and economical hydrometallurgical technique for extraction of mercury from its ores, particularly those too low in grade to allow economical metal recovery by retorting or furnacing techniques. Oxidation was accomplished by electrolysis of ere slurried with brine. Cinnabar was dissolved by oxidation of the insoluble sulfide to soluble mercuric salts. The mercury ion in a brine solution forms a stable tetrachloro complex. Typical laboratory experiments required I to 7 hours of electrolysis at 35-percent pulp density in a brine solution that contained 4 to 20 weight-percent sodium chloride (NaCl). Power consumption ranged from 10 to 50 kwhr/ton of dry ore. Mercury extraction values between 90 and 99 percent were obtained with all of the ores investigated. Subsequent mercury recovery from leach solutions was readily accomplished by precipitation on zinc. Pilot mill experiments in a 100- to 200-lb/hr extraction plant are in progress to quantify power and reagent requirements, and extraction and recovery data obtained to date closely parallel those obtained in the laboratory.

Jan 1, 1970

By Richard J. Leary

The inputs of capital and labor to support future iron ore production were developed by the Bureau of Mines from projections of iron demand and estimates of capital and labor requirements. Trends in technologic change and the organization of production were analyzed. Labor requirement schedules for iron ore mining and beneficiating were constructed from aggregate inter-temporal trends and 1970 cross-sectional analysis of mines and mills. A sup-ply schedule of the capital requirement for mine-mill-pellet plants was developed from U.S. and Canadian experience. The structure of demand for iron to the year 2000 was examined as well as the availability of resources. Projections of capital and labor requirements to 2000 were constructed under two international patterns of iron ore supply to the United States. The most likely model is for a continuation of the 70 percent United States-30 percent foreign shares, expanding at an average 2.0 percent growth rate to 2000, and supported by a cumulative gross capital investment of $3.8 billion constant 1967 dollars and a labor force in the United States of 29,800 by 2000. The information content of projections is discussed, and the possible effects of international forces on supply are considered. A generalized methodology for estimating capital and labor requirements in other mineral industries also is included.

Jan 1, 1975

By D. Harrington

[Notwithstanding the fact that it is now fairly generally recognized that widespread explosions can be almost absolutely prevented in coal mines by efficient rock-dusting and that this rock-dusting can be done thoroughly at a cost which should seldom exceed 1 cent per ton of coal mined, a recent survey of the situation by the Safety Division of the U. S. Bureau of Mines, following a similar survey by the Bureau in the fall of 1925, shows that while some progress is being made by our coal-mining people, many entire mining communities are lamentably slow in taking advantage of one of the most effective safeguards available. Much of the information as to the extent of rock-dusting was obtained through the various State inspection departments. Table 1 shows that in the fall of 1925 about 92 coal companies in the United States were using rock-dust ad that in the summer of 1927 the number had increased to 239, or about 160 per cent increase. Similarly, from the fall of 1925 to the summer of 1927 the number of mines using rock-dust increased from 177 to 463, or about 160 per cent increase. This appears to be a decidedly healthy increase, but when it is considered that in 1926 (the last date for which figures are available) there were 7,141 bituminous mines operating and that there were only 463 or 61 par cent, which were even reported to Ice using rock-dust to any extent whatever, the forgoing figures as to progress are by no means impressive or even satisfactory.]

Jan 1, 1928