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By ROBERT R. ROUGH, FRANK L. BACON, John Dasher

(being shipped as bailast in ocean freighters). Within the last 10 years it has become more economical to use local sands, and there has been a general shift from the Belgian sand. Deposits of purer sand were treated and used for 'some time: but the suprly became limited, and means were sought to beneficiate the more bountiful subpay-f impure beach sands. These sands are composed of, 50 percent feldspar and 50 percent quartz, with small amounts of iron- bearing minerals, The most objectionable impurities in these West coast sands are the oxides of iron and aluminum. The Del Monte (Calif.) beach sand contains about 0.13 percent FeqQg and about 11.0 percent Aig03 (the latter being furnished by the large amount of feldspar present.) For the manufacture of feldspar present.) For the manufacture of flint-glass containers the maximuni quantities of these two impurities permitted in the sand are 0.05 percent F20 and 6 to 8 percent A1203.. The Fe0g occurs in the sand as follows: Traces of iron-bearing minerais resistant to weathering, ferruginous clay stains on the sand grains, and iron minerais not visible and possibly in solid solution or as colloidal incisions in the grains of feidspar or quartz. A good part of the iron in the sand is present in the traces of iron-bearing minerals, biotite, ilmenite, garnet, monazite; and hornblende. Biotite is present in larger quantities than the others. Samples of quartz, were freed of iron-bearing minerais by the use of heavy liquid (sp.gr. 2.70), leached with boiling HCI and SnCl2. Under a microscope a few apparently clean quartz grains were selected, and Fe203 was determined spectrographically to be 0.03 percent. The technique is similar to that described by Gabriel and Slavin. 4/

Dec 1, 1943

By John B. Umhau

In 1930 , 65,448 long tons of virgin or primary tin were consumed by 1,292 establishments in the United States , representing about 91 per cent of the total consumption as computed from imports , exports , and stocks at the beginning and the end of the year . The reported consumption was equivalent to 38 per cent of the world's tin production in 1930 , estimated at 171,000 tons , and was 12 per cent less than the 74,369 tons consumed by 1,307 establishments in 1928 . Decreased consumption of new tin in 1930 ás compared to 1928 was a reflection of the general industrial depression . All of the tin- consuming industries showed substantial decreases except tin plate and terneplate , white metal , and tinning , which showed small tonnage increases aggregating only 1,200 tons . The largest tonnage decrease was in the use of new tin in babbitt which declined 33 per cent in 1930 as compared to 1928. This was largely attributable to the decreased production of automobiles and trucks , which was 24 per cent lower in 1930 than in 1928. Percentage decreases in other important tin- consuming industries were as follows : Solder 18 per cent , bronze 19 per cent , tin foil 40 per cent , chemicals 23 per cent , tin oxide 44 per cent , and type metal 46 per cent . The distribution of the amount consumed by various uses during 1927 , 1928 , and 1930 is shown in table 1 . Consumption studies indicate the fact that variation in tin consumption from year to year parallels the fluctuations in demand for the already wellestablished tin products . For example , the manufacture of motor cars and trucks3 required only 11,000 tons of tin in 1930 compared to 19,000 tons in 1928 ; the canning industry continues to require the greater portion of the tin plate and much of the solder . Recently developed industries , while affecting total consumption of bearing metals , solders , etc. , to some extent , have made little change in the relative importance of these commodities as consumers of tin .

Jan 1, 1932

By J. H. East

The occurrence of hydrogen sulfide in the gas in solution in the oil produced from the Tensleep sandstone in the Elk Basin oil field in Wyoming constitutes a serious hazard to persons working in, that field. Aware of the general conditions because of petroleum reservoir studies being conducted in that field by its engineers, the Bureau of Mine's willingly agreed to a request of the Petroleum Administration for War to publicize the hazard and the measures for overcoming it. In October 1943 and November 1944, the Bureau of Mines investigated the method's used in handling the oil and in disposing of the hydro¬gen sulfide that occurs with it. This circular reports the results of these observations. HYDROGEN SULFIDE OCCURRENCE IN THE. ELK BASIN OIL FIELD The Elk Basin oil field is in Park County, Wyo., and Carbon County, Mont. It is about 18 miles north of Powell and 12 miles west of Frannie, Wyo. The original Elk Basin oil and gas field was situated in an eroded depression surrounded by an inner rimrock about 200 feet high with a bordering higher plateau about 500 feet above the basin floor.

Jan 1, 1945

By A. W. Khair, M. Ahmad, Gehi. L. D.

"This paper presents an analysis of the effect of the dynamics of bit wear on dust generation. Two surveys have been conducted in order to assess the mechanism and type of bit wear and to evaluate the impact of bit wear on the productivity of the continuous miners. Used bits were collected from the underground coal mines and these used bits were utilized in laboratory coal cutting. The effect of bit wear on dust generation has been quantified and its impacted on dust generation and ventilation system has been exemplified.INTRODUCTION Research has reduced the prevalence of Coal Workers Pneumoconiosis from 15 to 5 percent according to NIOSH reports (Breslin 1982). However CWP still have not been eliminated as a hazard to mine workers. To prevent coal workers from having black lung MSHA has established a very strict standard for coal mine operations (2.0 mg/m3 with silica content equal to or less than 0.1 mg/m3,). There are numerous coal operations still experiencing great difficulty with meeting the 2mg/m3 dust standard. Among these are the longwall sections and continuous mining sections. In order to meet the rising demand of energy and coal, the number of longwall operations and continuous mining operations would have to be increased. Thus a long term research commitment is required to develop basic solutions that are more generic and greater benefit to the mining and mineral industry.In continuous-mining operations, the miners are exposed to the dust produced during the fragmentation of the coal from the face plus the dust produced during loading and transferring of the coal. The fragmentation process generates most of the respirable dust. The amount of dust generated during fragmentation depended on the coal properties, cutting parameters and cutting bit configuration. Bit wear changes bit configuration, therefore, it also affects dust generation. Bit wear can be defined as the removal of material from surface as a result of mechanical action. In soft coal mines bit wear may not be a serious problem but in hard coal seams bit wear is very significant. In addition, as the good coal seams are depleted, the operators are mining thin seams and the seams with rock partings. During cutting these seams operators are sometimes forced to cut roof and floor rock or rock partings which result in more rapid wear of bits."

Nov 1, 1995

By Richard A. Winters

The 31,880-acre Battle Creek Wilderness Study Area (WSA) was evaluated for mineral resources by the U.S. Bureau of Mines in 1984. No mining district is in the area, nor were any mines or claims recorded or found. Oil and gas leases, or lease applications, covered about half the area in early 1984. No known exploration has occurred. The entire WSA is covered with thick volcanic flows. Faults in these volcanic rocks may have provided conduits for mineralizing solutions emanating from the basement rocks; however, no evidence of mineral deposits was detected from rock samples collected along the faults. Reconnaissance samples from sand and gravel deposits yielded gold at less than $0.02/yd3. The source of the gold is assumed to be intrusive rocks or the Challis Volcanics about 20 miles north of the study area near the headwaters of Battle Creek. No economic concentrations of minerals were found in the WSA. INTRODUCTION Mineral surveys of designated wilderness study areas (WSAs) 1/ are conducted by the U.S. Bureau of Mines (USBM) and the U.S. Geological Survey (USGS) at the request of the U.S. Bureau of Land Management (BLM). The USBM researches the mining and mineral exploration history and evaluates mines, prospects, and mineralized areas within or adjacent to WSAs. The USGS studies WSAs by regional geochemical and geophysical surveys and geological mapping. The USBM and the USGS investigations are summarized in a joint report used to help determine the suitability of WSAs for inclusion into the National Wilderness Preservation System. Although the immediate goal of this USBM study is to provide data for the President, Congress, BLM, and the general public for land-use decisions, the long-term objective is to help insure that the Nation has an adequate and dependable supply of minerals at reasonable cost.

Jan 1, 1985

By V. A. Nieberlein

An extractive process was developed applicable to submarginal titanium deposits containing valuable minor constituents; such as columbium (niobium) and iron. The process consisted of reducing the mineral concentrate with coke at high temperature to form a carbide-suboxide sinter, chlorination in the 400° -500° C. range, and fractional condensation of the chlorides. The chlorination procedure recovered 97, 83, and 87 percent of the titanium from brookite, rutile, and ilmenite sinters, respectively, while simultaneous columbium recoveries on the same materials were 85, 50, and 87 percent.

Jan 1, 1957

By David A. Benjamin

From 1986 to 1989, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 59,600-acre Mexican Mountain Wilderness Study Area (UT-060-054) in order to evaluate its identified mineral resources. The study area is located in Emery County, UT, about 24 miles east of Castle Dale, UT. A review of the geologic and mining literature, and a field examination identified two uranium prospects in the Wilderness Study Area, and three copper prospects nearby. One-hundred ninety-five rock samples were taken.

Jan 1, 1989

[This is the eighth in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the interior. The fir t report gave data on motor gasolines sold during the winter of 1935-36.3/ The present report, covering 1,679 simples, represents the products of US companies plus those from the Pacific coast, witch were averaged by the Pacific Coast Technical Group before being submitted and arc published exactly as they were submitted. The three groups of data on samples of regular, premium, and third-grade gasolines are averred separately. the, number of samples and brands representing each grade are as follows: Regular price, 869 samples, 76 brands; premium price, 452 sample, 45 brands; third-grade 358 samples, 52 brands. In this report the same marketing districts are retained as were used in the preceding report, and as for as possible the actual sampling points in each area are indicated on table 1.]

Jan 1, 1940

By G. W. Jones

[As a part of its investigations pertaining to the promotion of safety, the Bureau of Mines is investigating various means, useful for the elimination or mitigation of the explosion hazards of combustible gases encountered in mining and industry. Information has been obtained and a procedure developed whereby the explosibility of many complex, gaseous, combustible atmosphere may be calculated in a simple manner without the necessity of performing laborious laboratory experiment. In a previous publication4/ data were given and a method described whereby the limits of inflammability of gaseous mixtures, including methane, hydrogen, carbon monoxide, nitrogen, carbon dioxide, and oxygen, could be determined by calculation. The information published in that retort enables one to calculate the limits of inflammability of such gases are liberated by mine fires, gases from explosives, automobile exhaust gas, gases present after mine explosions, blast-furnace gas, and other gases containing part of or all of the above-listed constituents.]

Jan 1, 1938

By W. H. Tomlinson

During the 9 years ended December 31, 1938, 188 fatalities resulted from preventable accidents in and around the coal mines of Indiana; 173 of these occurred at underground mines and 15 at stripping or open-cut operations. In addition, there may have been other unrecorded fatalities during this period. The two organizations receiving notice of accidental deaths at coal mines in this State are the Division of Mines and Mining and the Indiana Industrial Commission. Only deaths occurring at underground mines employing 10 or more men are reported to the former, as neither strip mines nor underground mines employing fewer than 10 men cone within the purview of the Indiana mining law. The mine inspectors have no Jurisdiction over this latter group of mines and do not inspect them. Fatalities at small "wagon" mines and open-cut operations are supposed to be reported to the Industrial Commission; however, in many instances deaths at small mines are not reported, the only record being a death certificate filed with the county or corporation health officer. Thus, many deaths in small mines escape attention, especially when the victim succumbs some time after the injury was received. The data presented here on fatalities in Indiana, during the past 5 years include several instances in which the only record available is a death certificate; possibly others have been overlooked. From 1934 to 1937 the fatality record was progressively worse, that of the larger underground mines in 1937 being more than twice the average for these mines for the previous 4 years and only slightly less than twice the average for all mines, including open-cut operations. The increase in deaths during 1937 was due to two explosions, with 20 fatalities in one and 2 in the other. The number of deaths in the larger underground mines was considerably less in 1938 than in the previous 4 years, but there was no improvement in the number of fatalities at the small mines, or at open-cut mines.

Jan 1, 1940

By J. T. McCartney

In an effort to correlate the size of pyrite particles in coal and coal-particle association with the removal of pyrite before burning, the Bureau of Mines conducted a study of 61 coals presently being used for electric power production. The results were obtained by visual microscopic studies of polished briquets of minus l4-mesh samples. Mean pyrite particle sizes ranged from 20 to 400 microns and proportions of pyrite contained in coal particles to an extent greater than 50 percent by volume (estimated) ranged from 20 to 95 percent. These parameters were correlated with reductions in pyrite accomplished by float-sink tests at 1.60 sp gr on 14-mesh, 3/8-inch, and 1-1/2-inch samples. The correlation coefficients between pyrite removal and mean pyrite particle size were 0.89, 0.84, and 0.79, respectively, for these samples. Correlation coefficients between pyrite removal and coal-pyrite association parameter were 0.92, 0090, and 0.85, respectively. It is apparent that extent of pyrite removal can be fairly well predicted from microscopic analysis.

Jan 1, 1969

By G. W. Jones

As a part of it investigations pertaining to the promotion of safety, the Bureau of Mines is investigating various means, useful for the elimination or mitigation of the explosion hazards of combustible gases encountered in mining and industry. Information has been obtained and a procedure developed whereby the explocibility of many complex, gaseous, combustible atmospheres may be calculated in a simple manner without the necessity of performing laborious laboratory experiments. In a previous publication4/ data were given and a method described whereby the limits of inflammability of gaseous mixtures, including methane, hydrogen, carbon monoxide, nitrogen, carbon dioxide, and oxygen, could be determined by calculation. The information published in that report enables one to calculate the limits of inflammability of such gases as are liberated by mine fires, gases from explosives, automobile exhaust ran, uses present after mine explosions, blast-furnace gas, and other gases containing part of or all of the above-listed constituents.

Jan 1, 1938

By Potts J. D.

Installation of a horizontal air-blocking shelf around the inside perimeter of the surface mining drill deck shroud is proposed to improve dust capture. Without the use of this shelf, a strong Coand? effect airflow pattern results in dust leakage to the environment, especially at the shroud-to-ground interface. Bailing air exits the drill hole and travels along the drill steel to the underside of the table, where it fans out across the bottom of the drill table and continues down the sides of the shroud. This dust-laden bailing air then strikes the ground and fans out under gaps between the shroud and the ground. The proposed shelf prevents dust-laden air from striking the ground by redirecting it toward the center of the enclosure, where it can be captured. Laboratory tests demonstrated that the shelf reduced dust levels outside of the shroud by 81% under operating conditions consisting of a 1.9:1 collector-to-bailing-airflow ratio and a 51-mm (2-in.) gap between the shroud and ground. The shelf was 152-mm (6-in.) wide and was located at a height equal to 2/3 the distance measured from the bottom of the shroud to the bottom of the drill table. The air-blocking shelf was also capable of overcoming the adverse impact of vertical leakage along the shroud seams as long as this leakage was confined to an area below the horizontal plane defined by the shelf location.

Jan 1, 2008

By Paul W. Jeran

Subsidence over a series of longwall panels undermining sloping terrain in southwestern Pennsylvania was monitored to verify the Bureau of Mines subsidence prediction model for the northern Appalachian coal region. Comparison of the field data to model output shows close agreement. Vertical movements over each panel ceased with the mining of the adjacent panel. Horizontal movements were significantly affected by topographic slope. The distribution of horizontal strains over each panel were similar, with a zone of compression occurring over the center of each panel. The zones of compression were flanked by zones of tension toward the rib. The magnitude of the tensions were affected by the slope. The strains developed at the completion of each panel were not significantly altered by the mining of subsequent panels.

Jan 1, 1988

By Jerry G. Craig

The Bureau of Mines has developed a computerized oil and gas well data retrieval system from studies of the waterflood potential of a producing reservoir. This system stores pertinent information about each well completed in a reservoir and facilitates selection and manipulation of large volumes of data. Use of the system enables reservoir information to be supplied rapidly, accurately, and at less expense.

Jan 1, 1971

By C. C. Merrill

Studies were made to determine the amenability of yttrium to fused-salt electrorefining in a controlled atmosphere. Tests were conducted in a LiCl- YCl3 electrolyte system at 710° C. The major variables studied were the YCl3 content of the electrolyte, from l.7 to 13.4 mol percent, and the initial cathode current density, from 410 to 1,630 amperes per square foot. Vacuum distillation was employed to remove salt from the deposited metal. Metallic impurities, except for lithium, could be reduced to near or below their lower analytical limits, ranging from 10 ppm for Cu to 300 ppm for Ta; reduction of oxygen content, however, was accomplished only in metal produced from electrolytes with 5.4 mol percent YCl3 or less. Initial cathode current density had little effect on the purity of the product.

Jan 1, 1967

By J. Koster

During the past several years, alunite from the Marysvale (Utah) region has been the subject of investigation by the Electrometallurgical Section of the Bureau of Mines. The nature and occurrence of this mineral, with considerable data on the Utah deposits, together with a number of results of preliminary experiments, have been given in a previous report.6/ The geology of the Marysvale region has been reviewed recently.7/ The present paper reports the results obtained by a method involving the sintering of alunite with boric acid and subsequent treatment of the sinter to produce alumina and potassium sulphate.

Jan 1, 1939

This is the eighth in a series of reports en properties of commercial meter fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the United States Department of the interior. The first report gave data en meter gasolines sold during the winter of 1935-36.3/ The present report, covering 1,679 samples, represents the products of 118 companies plus these from the Pacific coast, which were averaged by the Pacific Coast Technical Group before being submitted and are published exactly as they were submitted. The throe groups of data en samples of regular, premium, and third-grade gasolines arc averaged separately. The number of samples and brands representing each grade are as follows: Regular price, 869 samples, 76 brands; premium price, 452 samples, 45 brands; third-grade, 358 samples, 82 brands. In this report the same marketing districts are retained as were used in the preceding report, and as far as possible the actual sampling points in each area arc indicated on table 1.

Jan 1, 1940

By Michael G. Zabetakis, Israel Liebman, Henry E. Perlee

Flammability studies conducted to date on stratified methane - air and pentane - air mixtures in air indicate that location and extent of a flammable layer are affected by molecular diffusion , gas motion , and propagation of flame . In initially quiescent mixtures , the lower limit - of - flammability zone may be determined by assuming molecular diffusion alone governs mixing rate . The upper limit - of - flammability zone can be predicted in this manner only for stratified layers with small concentration gradients ( less than 0.2 volumepercent per inch ) ; where large concentration gradients are encountered ( for example , as much as 30 volume - percent per inch ) , the initial - mixture methane concentrations that yield flammable mixtures are larger than anticipated . Flames propagating through heterogeneous quiescent methane - air atmospheres in the direction of the concentration gradient exhibit flame speeds at any point that corresponds to the flame speed of the homogeneous gas mixture having the same gas composition as that of the point in the heterogeneous system . In flowing mixtures with large concentration gradients , the degree of mixing prior to ignition does not appear to affect the flame velocity and emitted radiation appreciably in a 6.5 - ft - diameter gallery .

Jan 1, 1964

By C. V. Davis

In the lnvestlg::ìt1on of mAthods for aSS8.7ing platin",. conducted by the Bureau ot MinAs, reoent experiments have d~velopad tha~ with ce..tain orei, especially when thr, quantity Of platinum 1s eonlidarablfl, nit'!le acid w111 not etfßct a iepard-Han of platinum and pa11adium. 'lhe following m;lthod has been found to be accurate and to reiu1 t in a complete S''lun''ation of' th~3:l metals. It is therefo 1" '!eeommei:ed that 1 t ba followed rath::r- than the method of separation with nitrio acid, givèn in Technical Pape'! 270.* At line 22, pagi 14, of that paper, bAglnnlng with ~tarm th,~ metals '.'ith dilute¡ nitrio acid," strikE out the rest of the paragraph, and substttutt~ the pro_t cedure g1 ven below. ?lunder and Thuringer.. have developed mnt¡iods for th"i sflparation of palladium from all the platinum metals exoept platinum bj m ,ans of dlmethy- 19lyoxlme. They state that the~ is no action for several hours if an excess of dimeth¡lglyoxime is added to an aqueous solution of ohloroplatinic acid in the cold, alio that only on boiling is the platinum pTecipi ated ¡~d than only PST't of the platinum i srenoved from the sUut1on. They found that palladium 1s p~ecipi tated quati tat! vely in the oold as (CaH 4N40 Pd) which is insoluble tn water, dilute hydroohlorio acid, dilute acetIc aofd or in 50~ ethyl alcbhol. All of their pT'90ipi tations we~p Carl". ied out ~hile the solutions were being heated. This caused a pal"tia~recipltation of the platinum along wi th the

May 1, 1922