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By J. S. Kennedy, M. M. Fine

"INTRODUCTION Barite is one of the major industrial minerals whose production has increased considerably in the last 10 years. In 1935 domestic production of barite was 218,075 tons and. had increased by 1944 to 515,136 tons. 3/ Most of the primary uses for barite and barite products were developed before 1935, so the increase in barite production reflects the growth of industry in general rather than any recent developments in barite technology.The principal uses for ground and crushed barrite are as a weighting agent in heavy drilling fluids, as a filler in rubber and other materials, as a pigment and extender in paints, and as a flux in glass melt. In addition, a considerable' quantity of barite serves as the raw material for the manufacture of lithopone and barium chemicals.Specifications for barrite vary widely and depend primarily on the use to which the material is put. The primary requisites for barite used in heavy drilling muds -are that it have a minimum specific gravity of 4.2 and be very,low in soluble salts. A minimun barium sulfate content of 92 percent may be specified; but this is less important than the gravity. 4/ In addition before consumption the material must be ground to '92 percent minus 325-mesh. 5/ Lithopone and chemical manufacturers require a minimum of 94 Percent barium sulfate, a maximum of 1.0 percent iron oxide, and not more than a trace of fluorine. 6/ Barite used as fillers in light-colored products should be of fairly high grade, but the filler used in dark products may be considerably lower grade.Glass barite should contain a minimum of 96 percent barium sulfate, not more than 3 percent moisture, a maxium of 0.2 to 0.4 percent iron oxide, and not more than a trace of titanium oxide. Particle size is a matter of some importance in glass barite, also. 7/"

May 1, 1948

By D. A. Reynolds, R. G. Travis, James J. Dowd, R. F. Abernethy

"1. Reserve estimates have been made for eight coal beds in Monongalia County, W.Va., but only the Pittsburgh, Sewickley, and Upper Freeport beds are important at this time. The Pittsburgh, Sewickley, Waynesburg, and Upper Freeport beds contain the largest recoverable reserves.2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 short tons per acre-foot of coal in place, are estimated at 3,526 million tons as of January 1, 1954. Of this total, 3,294 mil¬lion tons is in beds 28 inches and more thick. Areas in each bed except the Pittsburgh were omitted from the estimate because available data relative to the bed characteristics are too meager for making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.3. Recoverable reserves of coal have been estimated in beds 28 inches and more thick. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian region. The weighted average recovery for all beds in Monongalia County, as determined by this investigation, is 47.9 percent. This percentage is based on the total thickness of coal (less partings three-eighths inch thick or more) in the bed rather than on the thickness of the coal mined. Based on the weighted average percentage of recovery for all beds in Monongalia County, the recoverable reserves are estimated at 1,577 million tons as of January 1, 1954.4. Monongalia County coals of the major producing beds are of high-volatile a bituminous rank.5. The Pittsburgh and Lower Freeport beds in this county yield coal that can be used as metallurgical coal, especially when blended with low-volatile coals. The Lower Freeport coal is coked singly and in beehive ovens, and makes good metallurgical coke.INTRODUCTIONThe investigation to evaluate the reserves of coking coal was planned to cover three phases: (1) Estimation of known measured and indicated recoverable reserves of all coking coal; (2) study of methods of upgrading marginal coals through effective preparation; and (3) study of carbonizing properties of coals and coal blends not now widely used for metallurgical coke making."

Jun 1, 1956

By Ruth F. Brinkley

Principle activities of the Bureau of Mines Explosives Research Laboratory from July 1, 1960 to June 30, 1961 are reviewed briefly in Part 1. Part 1 also includes data obtained in connect ion with several minor investigations which are not sufficient to warrant separate publications. Part 2 gives brief abstracts of publications that appeared during fiscal year 1961; in general, the research reported in these publications antedates this period.

Jan 1, 1963

By Paul M. Tyler

"In preparing this paper the writer has perforce depended mainly upon published information, including the catalogs and pamphlets issued by importers and dealers such as the Diamond Drill Carbon Co. and J. K. Smit & Zonen. Special acknowledgment is made to various articles published by S. H. Ball. The writer of this paper, however, is alone responsible for statements herein contained and since he has often found it necessary to rationalize apparently conflicting opinions of recognized authorities on this little-known subject, he will welcome constructive criticism from the trade.Two types of diamond are extensively used for industrial purposes. One type, known as bort or bortz (boort, boart, bowr, etc.), consists of diamonds of the gem variety but unfit for cutting into gems. They may be colorless, yellow, brown, or gray. The other type, carbonado, known in the trade as ""carbon"" or ""black diamond,"" differs greatly from the white diamond, being opaque and apparently amorphous or noncrystalline. Actually, instead of forming a large single crystal as in a gem stone, carbon diamond comprises a mass of microscopic crystals that interlock to form a tough, homogeneous material with no planes of cleavage. It is found in various colors -- black, dark green, brown, and gray -- but usually it has .a dark lustrous black surface, with a resinoid or submetallic appearance, often resembling fine-grained steel. Upon exposure to the air the broken surface gradually darkens to an ash-gray color. Ballas is a special type of carbonado in which the crystals are definitely-oriented around a central nucleus. They are harder and tougher than ordinary carbonado but are much scarcer. The Cape ballas is reputed to be not quite so tough as Brazilian ballas but tougher than carbon or bort.The diamond crystals are isometric and take a variety of forms. The cleavage is octahedral and well marked. A crack is easily -started parallel to an octahedral face, and bort or gem diamonds are notoriously brittle, especially when subjected to sudden shock. Even carbonado, while it has a high resistance to slowly applied pressures, may be chipped or broken by a sharp blow.Exposed to radioactive rays, the diamond becomes phosphorescent; this property is often utilized to distinguish it from quartz, topaz, or glass. The unusually high refractive index likewise aids in its identification in the case of a more or less transparent stone. At the temperature of the electric arc, diamond is converted into graphite, another form of Carbon but one of the softest mineral substances. At a much lower temperature, as low as 1,5620 F., the diamond may be burned like ordinary carbon in an atmosphere of oxygen, and according to some authorities there is danger of burning a diamond if overheated even in air."

Mar 1, 1932

By S. Don Brown

Between 1987 and 1988, the Bureau of Mines studied the mineral resources of the White River National Forest and part of the Arapaho National Forest to appraise the resources present and to determine the types of deposits, and their location, that could be mined economically if sufficient demand and metal prices existed. The study included a comprehensive literature search and a limited amount of field investigation of minerals and mining activity in and near the Forest. This report summarizes a more comprehensive minerals report on the Forests prepared by the Bureau of Mines and was written for a general audience without a background in geology or related fields. Mineral resource information indicates that in the Gore Range-the area between Tennessee Pass and Gilman may contain large base-and precious-metal deposits, and could be the focus of exploration activity in the near future. The Breckenridge mining district was found to have a moderate to high likelihood for mineral exploration and possible development of gold. Recent exploration and minor development work has occurred in several other areas: Montezuma, Kokomo-Tenmile, and Upper Blue River districts, and portions of the Sawatch Range.

Jan 1, 1990

By G. M. Molinda

The U.S. Bureau of Mines conducted an investigation to determine the nature and frequency of coal mine roof failure beneath valleys. A mechanism for this failure and suggestions for controlling this problem are presented. Hazardous roof conditions identified in some mines were positively correlated with mining activities beneath stream valleys. Mine maps with overlays of unstable roof and locations of stream valleys show that 52 pct of the instances of all unstable roof in the surveyed mines occurred directly beneath the bottom-most part of the valley. The survey also showed that broad, flat-bottomed valleys were more likely to be sites of hazardous roof than narrow-bottomed valleys. Evidence of valley stress relief was found beneath several valleys in the form of bedding plane faults and low-angle thrust faults. This type of failure, previously believed to be only a shallow phenomena, was found at mining depths as great as 300 ft. In situ, horizontal stress measurements beneath a valley and the adjacent hillsides, confirmed valley stress relief. Numerical analysis of 13 valleys overlying one mine property showed the effect of the valley excavation on horizontal and vertical stress.

Jan 1, 2010

By H. C. Young

This paper deals with roof bolting in Alabama coal mines and iron-ore mines from the time it was introduced in early May 1948 to May 1, 1953, a 5-year period. The Tennessee Coal & Iron Division of the United States Steel Corp. began systematic roof bolting in early May 1948 in a coal mine and in an iron-ore mine, which had some of the poorest roof conditions in the Alabama mines. After the efficiency of roof bolting had been proved by the Tennessee Co. it was gradually adopted by other companies throughout the State, until in May 1953 approximately 53 percent of Alabama's total coal production and 100 percent of Alabama's total iron-ore production, mined underground, was being produced from roof-bolted areas. Statistics in this report will show the advancement made in roof bolting in the 5 years and also the amount of roof bolting that was being done as of May 1, 1953. Significant progress has been made in the coal and iron-ore mines of Alabama in reducing the roof-fall fatality rates during the past several years by adopting systematic roof bolting. The groundwork was laid through successful experiments early in 1948 by the Tennessee Coal & Iron Division of the United States Steel Corp. in cooperation with the Federal Bureau of Mines. This experimental work was based upon the previous experience of the St. Joseph Lead Co.2/ in its Southeastern Missouri mines.

Jan 1, 1954

By Charles E. McCarthy, MORTON T. PAWEL, E. A. GEE, FRANK S. RIORDAN

Large tonnages of the magnesium silicate mineral , olivine, are known to exist in the mountains of western North Carolina and in the Puget Sound region of Washington. The North Carolina deposits alone are reputed to contain at least 230 million tons of ore averaging 45 to 49 percent of magnesium oxide In both areas the mineral is readily accessible and can be mined by the simplest methods ; one of the largest of the Washington deposits is located at tidewater .

Sep 1, 1946

By Frank E. Cash, Max S. Petersen

The use of safe equipment, safeguards, and safe practices in the mining and allied industries should reduce injuries and improve accident experience. The object of this report is to give to the mining industry, especially metal mining, a graphic pictorial description of some of the safeguards, equipment, and practices used and followed in the iron-ore mines of the Lake Superior district. Some of the subject material has been in use or has been established for many years, and some is relatively new. Some of the equipment was purchased commercially, and some was designed by the company employees and constructed in the mine shops. The photographs were taken by the personnel of the Health and Safety Division of the United States Bureau of Mines, primarily for use in the Metal-Mine Accident-Prevention Course of the Bureau of Mines. In general, they are arranged under the following headings or subjects: 1. Accident statistics. 2. Support of ground. 3. Hoisting and haulage. 4. Explosives. 5. Fires, gases, and ventilation.

Oct 1, 1948

By Otto L. Schumacher

The Overthrust Belt in portions of Montana, Idaho, Utah, and Wyoming, an area that has contributed generously to the Nation's mineral supply, is one of the few remaining oil and gas frontiers on the North American continent. Determination of the oil and gas potential and development of mineral resources of the area have been affected by a variety of land withdrawals and other restrictions, The purpose of this study is to determine the extent of these withdrawals and restrictions and to discuss the mineral resource potential within the study area. Statistics in this report refer to land status on January 1, 1979. At that time, of the 27.3 million acres of Federal mineral lands within the study area, applications tor Federal oil and gas leases for more than 4,4 million acres (about 16 percent) were pending; the average length of time was 2 years. Federal oil and gas leases covering 8.8 million acres were also on record. Although drilling has occurred on some of these leases, others are subject to restrictions that discourage or prevent development. Some in fact contain stipulations disallowing any development.

Jan 1, 1981

By Ned H. Snyder

In recent years the Government and other large consumers of coal have appreciated more and more the desirability of definitely determining by chemical analysis and test the character and quality of the coal they purchase. Higher prices for coal point forcibly to the need of giving more study to engine room and boiler room efficiencies and economies; this implies an intimate knowledge of the character and quality of the fuel used. Analyses and tests of delivered coal furnish data whereby power plant results can be comprehensively studied and a continuous check maintained on the coal and on the conditions of plant operation. Under authority of acts of Congress making appropriations for technologic investigation of fuels and the analyzing and testing of fuels belonging to or for the use of the United States Government, a laboratory is maintained at the Pittsburgh station of the Bureau of Mines, where samples representing deliveries of coal purchased for Government use are analyzed and tested. The Bureau of Mines has been active in promoting the purchase of coal by the Government under specifications/ that is, by contracts that make definite requirements regarding the heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analysis. Under many of these specification contracts the bidders guarantee the quality of the coal offered, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled and analyzed to determine whether the coal is of the quality guaranteed by the contractor, and if it is not, the price to be paid is decreased in proportion; but if the coal is of higher quality, the price is proportionately increased. The known analyses of coals or the guaranteed analyses offered by the bidders may sometimes be used for determining the award of a contract, but if the coals offered differ widely in characteristics, it may be difficult to determine which would prove the cheapest fuel without data on their relative evaporative efficiencies. Hence, the making of evaporative tests under service conditions may be necessary in order to determine which coal is particularly adapted for successful and economical use in a certain plant. Once a particular coal is selected, however, regardless of the procedure of determining the award of a contract, then the greatest advantage of the specification method is realized, for it guarantees the purchaser receiving coal of uniform character and quality, thereby insuring the best results in the plant. The success of the specification method for the purchase of coal and the reliability of analysis now rests largely on sampling.3 Improper sampling leads to controversies, with resulting condemnation of the specification method in general and of the value of laboratory analyses and tests in particular.

Jan 1, 1922

By John J. Mulligan

The Bureau of Mines investigated the tin deposits of the Cape Mountain area during July and August 1962 to test the effectiveness of detrital-cover sampling in permafrost areas as a relatively cheap and simple means of guiding mine development and exploration. Results indicate that systematic detrita1-cover sampling can be used effectively to delineate obscure deposits with sufficient accuracy to permit sampling with a minimum of trenching or drilling. Extensions of known outcroppings were traced in sufficient detail to guide lode sampling and several previously unknown tin-bearing lodes were found and sampled. Lode sampling was limited to the minimum needed to establish the reliability of detrital-cover sampling results. The results of previous lode and placer investigations are summarized and detrital-cover sampling methods and results are described in detail.

Jan 1, 1966

By A. T. Iannacchione, D. G. Puglio

The Bureau of Mines established geologic factors affecting the mining of the Lower Kittanning coalbed to aid in coalbed minability studies and examined the occurrence of "wants" (places where coal is missing) and types of unstable roof rock strata. Trends established from mapping, including prediction of areas of high methane emissions, were extrapolated to unmined areas. "Wants" in the coalbed are of two types: Erosional and depositional. Erosional features occur where north-south-trending sand-filled channels cut into the coalbed. Variations in depositional environments have caused the coalbed to "split" into several thinner units. Slickensides, commonly indicative of unstable roof, are adjacent to and on the underside of sandstone channels; they were caused by differential compaction and by soft sediment sliding along the contact between the sandstone and adjacent shale. The frequency of unstable roof also increases where the interval between the Middle and Lower Kittanning coalbed is less than 30 feet. The zones of weakness at the contacts above and below the Middle Kittanning coalbed are the controlling factors for unstable roof in these strata. Methane emissions from the coalbed are controlled primarily by depth, fracture permeability, and rank of coal. Local geologic factors are coalbed thickness, associated rock strata, structure, and proximity to outcrop.

Jan 1, 1979

By George Markon

The rapid growth and development of the Soviet coal industry rank the U. S. S. R. with the United States among the leading coal-producing countries. The coal resources of the Soviet Union are among the largest in the world, although coal development has been hindered by the disadvantageous location of the coal deposits with respect to the major consuming centers. Although coal production in the U. S. S. R. reached a record high, the total energy output of mineral fuels in 1957 was still far below that of the United States because a significant part of Soviet coal output was lignites or lower rank coals. Although the Soviet coal industry soon may exceed that of the United States in tons produced, the energy equivalent of Soviet output will be considerably less because of the inclusion of a high percentage of lower rank coals. Energy sources in the United States also involve large quantities of oil and natural gas, whereas coal supplies most primary energy in the Soviet Union.

Jan 1, 1959

By James Paone

Land utilized by the mining industry from 1930 through 1971 amounted to 3.65 million acres, or 0.16 percent of the land mass in the United States. Land reclaimed during the same period was 1.46 million acres, or 40 percent of the land utilized. This report includes data on land use for wastes from underground and surface mining, for wastes from mill operations, and on subsidence. Data on land use and reclamation were obtained from operating companies, mining organizations, appropriate State agencies, and others concerned with such activities. The 10 leading States in land used for mining in 1971 were, in decreasing order, Kentucky, Pennsylvania, Arizona, Ohio, California, Florida, West Virginia, Illinois, Minnesota, and Indiana. Mineral commodities accounting for a major portion of land use are, in decreasing order, bituminous coal, sand and gravel, stone, copper, phosphate rock, iron ore, and clay; for coal, these commodities are produced principally by surface mining operations. Reclamation over the 42-year period was largely on lands utilized for surface mining of bituminous coal. New surface mining methods, particularly for coal, incorporate some form of land restoration.

Jan 1, 1974

By R. A. Friedel

THE IMPORTANCE of infrared and ultraviolet-visible spectrometry in studies of the structure of coal and similar substances is described. Special experimental techniques have been developed for these studies. Thin sections of coal are preferred, but halide pellets are easier to prepare. Information obtained from infrared spectra on chemical functional groups has been discussed; the importance of both intensities and wavelengths of absorption bands has been emphasized. Functional groups assigned include aliphatic and aromatic CH, methylene and methyl groups, hydrogen-bonded hydroxyls, hydrogen-bonded and chelated carbonyls, phenolic structures, minerals, and aromatic structures that are benzenoid or polynuclear. Infrared studies of structures of coal extracts, distillates, and reaction products of various processes, both chemical and physical, are discussed. Coallike infrared spectra of chars of model compounds have been utilized extensively in studies of coal structure. Ultraviolet-visible absorption spectra of coals show a lack of fine structure and low spectral intensities. These results have been applied to the questions of the chemical and physical structure of coal, particularly the question of polynuclear aromaticity of coals. The color of coal is also treated. The physical-chemical origin of the color of coal may be due to free radicals, as interesting correlations of ultraviolet-visible spectra with electron paramagnetic resonance have been obtained. The optical color of coal has been explained and simulation of the color changes observed in thin sections has been carried out, The spectra and structure of coal derivatives and other carbonaceous materials are also discussed. Possible sources of error in absorption spectral measurements are pointed out. Limited measurements of the ultraviolet-visible reflectance spectra of coal are described.

Jan 1, 1967

By Thomas L. Vandergrift

To significantly increase the stability of underground excavations while exploiting the full advantages of confined rock strength, methods must be developed to actively control the distribution of stresses near the excavation. This U.S. Bureau of Mines study examines theoretical and practical aspects of rock pres¬surization, an active stress control concept that induces compressive stress in the wall rock through repeated hydraulic fracturing with a settable fluid. Numerical analyses performed by incorporating the rock pressurization concept into a variety of boundary-element models indicate that rock pressurization has the potential to improve underground excavation stability in three ways: (1) by relocating stress concentrations away from the weak opening surface to stronger, confined wall rock; (2) by inducing additional stresses in a biaxial stress field to reduce the difference between the principal stress components near the surface of the opening; and (3) by counteracting the tensile stresses induced in the rock around internally loaded openings. Practical aspects of the rock pressurization concept were investigated through a series of hydraulic fracturing experiments. The use of sulfur as a settable fluid for hydraulic fracturing was demonstrated, although problems related to sulfur viscosity suggest that other molten materials, such as wax, may be better suited to practical field application of the rock pressurization concept.

Jan 1, 2010

By John R. Reigart

The Tri-State district, as its name indicates, is composed of portions of three States, the southeastern corner of Kansas, the northeastern corner of Oklahoma, and an adjacent strip of Missouri east of these portions of Kansas and Oklahoma. An area approximately 40 miles long in a northeasterly-southwesterly direction, and 30 miles wide at right angles thereto, containing minable occurrences of ore at widely scattered locations, comprises the district. However, what has been and is the main productive area, is a strip about 35 miles long and 10 miles wide, which begins at Miami, Okla., as its southern extremity and runs in a northeasterly direction through Commerce, Picher, and Hockerville, Okla., Baxter Springs and Galena, Kans., and Joplin, Webb City-Carterville and Carthage, Mo. Almost the entire present production comes from the area between Commerce and Baxter Springs.

Jan 1, 1932

By James J. Dawd

The investigation to evaluate the reserves of coking coal is being made by the Bureau of Mines in three parts: (1) To estimate known measured and indicated recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the ninth of a series of reports giving results of studies by counties under part (1) of the investigation. (See Appendix.) This report covers Raleigh County, W. Va., which comprises parts of Bald Knob, Eccles, Beckley, Meadow Creek, Mullens, Flattop, and Big Bend quadrangles. (See fig. 1.) A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, location of drill holes, bed and total coal thickness, and outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick. These areas of coal reserves also were divided into measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas. areas excluded from the estimate but which may contain reserves based only on geologic inference, and areas outside of the outcrop were measured by planimeter on the base maps, Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1952

By J. L. Johnson

The U.S. Bureau of Mines investigated the recovery of tin and silver from the Coal Creek deposit in the Talkeetna Mountains, AK. Approximately 5 million st of reserves grading 0.2 pct Sn with silver credits of 0.2 tr oz/st have been delineated by drilling. A 10-to 25-pct Sn gravity concentrate was produced by treating the minus 20-mesh ore with a spiral, then regrinding to minus 65 mesh and tabling. Sulfide contamination in the gravity concentrate was as high as 60 pet. Sulfide flotation of this concentrate produced tailings containing 40 to 50 pet Sn. Overall recovery was 76 pct for tin but only 5 to 10 pct for silver because of losses during sulfide flotation. Other methods tested to clean the concentrate included cassiterite flotation, gangue flotation, nitric acid leaching, and wet and dry magnetic separation. Tin beneficiation tests on the minus 325-mesh fraction included cassiterite flotation, vanning, sulfide flotation, and fuming. The bench-scale and locked-cycle tests were used to estimate the mass flows for a 1,000-st/d plant.

Jan 1, 2010