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By A. D. Garman

This paper presents one of a series of digests of foreign mining legislation and court decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the laws of Japan has been prepared from the best available information in Washington but is released subject to correction and amplification , if necessary , by the proper American diplomatic and consular officers to whom it is being referred through the courtesy of the Department of State . It is based on the law and regulations of 1905 as revised in December , 1915 , and translated by J. de Becker , LL.B. Occasional words and phrases quoted herein are accordingly taken from this translation and have not been checked against the original . The references are to the law ( as distinguished from the regulations ) unless otherwise stated .

Jul 1, 1930

By I. AITKENS

The opal , long in disfavor because it was considered " unlucky, " has become much more popular in recent years . For variety and beauty of color the precious opal is without a peer . These colors do not come from any chemical constituent but are produced by structural peculiarities , which in varying degrees deflect the light rays entering the stone and give a prismatic play of hues .

Sep 1, 1931

By W. W. Weller

Low-temperature heat capacity measurements were conducted, and entropies at 298.15° K were evaluated for sodium monomolybdate (Na2Mo04), magnesium monomolybdate (MgMo04), and calcium monomolybdate (CaMo04). The 298.15° K entropy values were sodium monomolybdate, 38.1±0.3 cal/deg mole, magnesium monomolybdate, 28.4±0.2 cal/deg mole, and calcium monomolybdate, 29.3±0.2 cal/deg mole.

Jan 1, 1963

By Eric E. Cather

In 1981 the U.S. Bureau of Mines and U.S. Geological Survey conducted a mineral survey of the 5,100 acre (2,065 ha) Rubicon RARE II area (No. 5026) in the El Dorado National Forest (fig. 1). Work by the Bureau of Mines indicates that potential for mineral resources in the area is low. Samples from small gravel deposits along the Rubicon River and from favorable structures in the area contained smart amounts of economic minerals. A Tertiary river channel near the north area boundary contains gold values as much as $137.60 per cu yd ($180 per cu m) [(gold at $400 per troy oz ($12.86 per g)]. The channel does not cross the study area. Energy resource potential, including oil, gas, or geothermal, does not exist in this geologic environment.

Jan 1, 1982

By R. V. Ramani, S. Shankar

"The phenomenon of re-entrainment is seen in environments such as sand dune formation, soil erosion, fugitive dust emission and the spread of radionuclides from accidents involving nuclear weapons. A thorough review of existing literature reveals that work on re-entrainment of dust in mine atmospheres is scant. The present study was undertaken as a part of ongoing research at the Generic Mineral Technology Center on Respirable Dust at the Pennsylvania State University on the development of methods to predict ambient dust concentrations in mine atmospheres (Ramani, 1983). The contribution of re-entrainment to the spatial and temporal concentration of dust in mine airways is being studied. The research has included wind tunnel and in-mine studies.A set of seven experiments was performed under controlled conditions in the US Bureau of Mines' Lake Lynn Laboratory mine. Two types of source coal dust, anthracite and bituminous, were subjected to various airflow rates and were subjected to walking by two different individuals. Six sets of instruments were used along the test section for sampling airborne particles. The average air velocity just above the coal dust bed varied between 2.1 to 3.2 m/sec.Due to re-entrainment as a result of the airflow conditions, the average respirable dust concentration in the center of the mine airway increased to 0.09 mg!m3 (standard deviation= 0.03 mg/m3)from an initial value of 0.02 mg/m3. The concentration of all (total) airborne dust increased to 0.17 mg/m3 (standard deviation = 0.10 mg/m3) from an initial value of 0. 02 mg/m3. The action of people walking, however, caused higher amounts of re-entrainment. The average concentration of respirable and total dust at the center of the mine airway increased to values of 0. 28 mg/m3 (standard deviation of 0.12 mg/m3) and 1.53 mg/m3 (standard deviation of 1.0 mg/m3), from initial values of 0.03 and 0.05 mg/m3, respectively. Jr was observed that the dust concentrations were much higher near the floor, immediately at the end of the coal-dust bed.Depending on the level of activity and the amount of dust deposited in the mine airways, re-entrainment may become an important source of airborne dust in areas away from the point of actual mining."

Dec 1, 1996

By R. L. Andrews

The Bureau of Mines investigated means of electrodepositing iridium to form thick coatings suitable for the protection of such metals as tungsten and molybdenum, which oxidize rapidly at high temperatures. Using a fused sodium cyanide bath, thick, adherent, and coherent deposits of iridium up to 15 mils thick were plated on tungsten and molybdenum substrates at 600° C and current densities of 10 to 100 ma/cm2. Limited oxidation testing of molybdenum encapsulated with pure iridium indicates that the coating may offer protection to approximately l,000° C in flowing air, but that at higher temperatures, the volatility of its oxide limits use of pure iridium. Alloy coatings of iridium with platinum, palladium, and rhodium up to 4 mils thick were formed from a fused sodium cyanide electrolyte; because their oxides are less volatile, these alloys may protect substrates at higher temperatures. Deposits made from aqueous electrolytes either had very low rates of deposition or were highly stressed and cracked when heavy deposits were made.

Jan 1, 1967

By H. R. Shell

The systems MgO-MgFa-SiO2, at 2 and 4 weight-percent Li2O and at 3.8 and 7.7 weight-percent Na2O were investigated by solid state reaction at 1,200° C. The results are summarized in four ternary diagrams. Besides the expected humites and simpler silicates or fluorides, proto-amphibole and water-swelling fluormicas or fluormontmorillonoids were found in the systems containing lithium and monoclinic fluoramphiboles, water-swelling fluormicas or fluormont-morillonoids, and nonwater-swelling fluormicas were found in the systems containing sodium. These latter compounds were not in the base system MgO-MgF2-SiO2.

Jan 1, 1962

By J. W. Paul

Mine foremen are employed in coal mines for two reasons: First, so that the underground work. may proceed in an orderly manner and that each employee gives attention to his duties; and second, by reason of the State law which re- quires the employment of such officials to see that the laws relating to safety are carried out. It may be seen that, with these two duties, the foreman has wide scope of authority and much responsibility. As foreman of operations he has to meet certain economic questions that contribute to the cost of producing the coal, and as the agent of the State he must also supervise and coordinate the work in such manner as to insure that the employees work under safe conditions. As the roof of coal mines is the source of the greatest hazard naturally the care of the roof must take much thought and planning on the part of the fore- man; and this circular is therefore presented to call attention to some things he may do to prevent injury to the workmen by falls of the roof material or coal. Mine foremen, in the principal coal-producing States, are certified by a State board which prescribes certain qualifications, experience, and character, attested by examination and personal endorsement. Certified foremen, therefore, are men who have had experience underground and know roof conditions and timber- ing methods. The suggestions herein are based upon observations made at many mines and collectively embrace practices that have been found to be in effect and pro- moted by experienced mine foremen:

Sep 1, 1930

By John M. Gomes

The Bureau of Mines investigated two techniques for removing CaO from scheelite (CaW04) prior to electrolysis. In the first technique, a crude tungstic oxide (WO3) containing 0.15-percent lime (CaO) was prepared by digesting scheelite concentrates in hot hydrochloric acid. This oxide was used as cell feed to produce tungsten of 99.9-percent purity. The second technique used a high-temperature, two-phase separation, resulting in extraction of 99 percent of the WO3 in the halide-tungstate phase, while 90 percent of the CaO was retained in the silicate phase. Tungsten of 99.9-percent purity was deposited from the halide-tungstate melt after B203 and NaPO3 were added to form an electrolyte. The two methods were compared with a previously developed technique of depositing tungsten from scheelite concentrate fed directly to the electrolytic cell.

Jan 1, 1971

By R. V. Ramani, C. B. Manula, A. Owili-Eger

• MINE VENTILATION NETWORK PROBLEM (NATURAL SPLITTING; FIXED • QUANTITY BRANCHES; METHANE SIMULATION; NETWORK TOPOLOGY REVISION; • ABSOLUTE PRESSURE) • NFIXB = NO. OF FIXED QUANTITY BRANCHES • DD(I) = AIR QUANTITY ASSIGNED TO FIXED QUANTITY BRANCH I, IN KCFP • NFBPF = NO. OF FIXED QUANTITY BRANCHES PLUS FAN • NFBPFG = NO. OF FIXED QUANTITY BRANCHES PLUS FAN PLUS METHANE • EMISSION BRANCHES • NBWNVP = NO. OF BRANCHES WITH NATURAL.VENTILATION PRESSURE • NVP(I) = NATURAL VENTILATION PRESSURE ASSOCIATED WITH • THE I-TH BRANCH • NF = NUMBER OF FANS • NB = NUMBER OF BRANCHES • MAXIT = MAXIMUM NUMBER OF ITERATIONS • MAXJ = MAXIMUM NUMBER OF JUNCTIONS • NJ = NUMBER OF JUNCTIONS INVOLVED IN THE SOLUTION * NM = NUMBER OF MESHES • NP = NO. OF POINTS TO DESIGNATE FAN CHARACTERISTIC * Q = QUANTITY OF AIR FLOW IN KCFM • R = RESISTANCE OF AN AIRWAY • WIDTH = AIRWAY DIMENSION • LENGTH = AIRWAY DIMENSION • HEIGHT = AIRWAY DIMENSION • SUMNVP = SUMMATION OF NATURAL VENTILATION PRESSURE FOR ANY MESH • X (I) = QUANTITY OF AIR, IN KCFM, ASSOCIATED WITH THE I-TB POINT • ON A FAN CHARACTERISTIC • E = ERROR FOR CONVERGENCE • FF = FRICTION FACTOR • FX(I) = FAN PRESSURE, INS INCHES OF WATER GAGE, CORRESPONDING • • TO A QUANTITY X(I) • H = HEAD LOSS IN INCHES OF WATER GAGE • I = BRANCH NUMBER • J, J1, J2 = JUNCTION, J1 AND J2 ARE TWO NODES WHICH DEFINE A • BRANCH • KEY = NO. WHICH SIGNALS THE TYPE OF FAN CHARACTERISTIC TO BE • EXPECTED

Jan 1, 1975

By Emory Smith

The preface of the United States Bureau of Mines Manual of First Aid Instruction contains the following paragraphs: One of the most important inquiries that Congress has authorized the Bureau of Mines to conduct relates to health condi- tions among those engaged in the mineral industries. Investigations made early with a view to bettering these conditions demonstrated the need of prompt care of injured miners, as, under the difficulties inherent to mining and other mineral industries; wounds seemingly unimportant, if not treated promptly, may become infected and possibly cause permanent crippling or even death of the porach. In the past many seriously injured persons have been treated by fellow workers ignorant of approved means of treatment and transportation and have been handled in such a manner as to cause suffering and to accentuate injuries to such a degree as to bring about permanent disablement. Accordingly, the need of general instruction in first aid became apparent. It must be recognized that the conditions in and about the mines, mills, smelters, quarries, oil fields, etc., usually present difficulties not found in large industrial centers where experienced surgeons are available and hospitals close at hand. Many mines are isolated and, when an accident occurs several miles underground, there may be a serious lapse of time before the injured person can be brought to the surface and taken to the hospital or given attention by a sur- geon who may have to come a long distance. Under such conditions it has been frequently demonstrated that, if effective first aid is not given, the injured person may die or become permanently crippled... First-aid instruction has been found to be an excellent aid3in pre- venting accidents. In addition to the immediate relief of injured persons, it has been found that most persons while in the act of practicing dressings for

Apr 1, 1931

By G. J. Conroy

This Bureau of Mines study was initiated to determine whether or not a large-scale investigation of 400-Hz applications in coal mines was justified as a means of increasing safety in operations due to size and weight reductions in portable and other mining machinery. Potential uses for 400-Hz power in mining operations are explored, and cost and size comparisons with 60-Hz systems are made. The use of variable-frequency motor drive is suggested for conveyors. The conclusion was reached that there is no significant potential safety increase due to a general size and weight reduction, as the fact of such general reduction cannot be demonstrated.

Jan 1, 1974

By R. E. Mussler

Electrowinning of copper from chloride solutions in a diaphragm cell was studied by the Bureau of Mines. The copper powder product was shaken periodically from the cathode and removed from the bottom of the cell. The effects of copper concentration, brine concentration, copper chloride species, and cell voltage were investigated. Power consumption of 1.1 and 2.1 kW-hr/kg were obtained with cuprous and cupric chloride solutions, respectively.

Jan 1, 1975

By Paul W. Johnson

An evaluation is made of a lime-soda sinter process for extracting alumina from anorthosite. In this process, alumina is extracted by sintering anorthosite with soda ash and limestone, and then leaching the sinter with a dilute sodium carbonate solution. The sodium aluminate solution formed during leaching is separated from the residue and treated with lime in autoclaves to remove dissolved silica before alumina trihydrate is precipitated with carbon dioxide. The trihydrate is then calcined to a-alumina. Two options, dry grinding and wet grinding, are used in the sintering step. For plants producing 1,000 tons of alumina per day for the dry grinding and wet grinding options respectively, the estimated operating costs are $75.40 and $74.36 per ton of alumina when charging $2.50 per ton for anorthosite and $1.00 per ton for limestone. The fixed capital costs based on a Marshall and Stevens chemical equipment index of 240.0 are $76 million and $70 million respectively. This process, when treating anorthosite, using either option, is not competitive under current economic conditions with the Bayer process treating bauxite to produce alumina.

Jan 1, 1968

By V. R. Miller

The Bureau of Mines has developed a technique to separate and recover the three major components, Pb, Zn, and Cd, from lead smelter flue dust. This research was conducted as part of the Bureau's effort to reduce environmental conflicts and occupational hazards associated with mineral-processing operations and to recover valuable constituents in emissions and effluents. The laboratory process utilizes sulfation roasting of the flue dust followed by water leaching to extract over 95 pct of the cadmium and zinc. Ninety-nine percent of the cadmium was recovered from solution by cementing with zinc dust, and zinc was electrowon from the resulting solution after purification. Zinc electrolysis was carried out in a 1-liter cell at 35° C with a cathode-current density of 8 A/dm2 in a solution containing 65 g/l Zn++ and 180 g/l H2S04, Current efficiencies of 80 pct were obtained. The leached residue consisted largely of PbS04, which was converted to PbC03 and leached with H2SiF6 to produce PbSiF6 electrolyte. Ninety-five percent of the lead contained in the residue was converted to electrolyte. Lead was electrowon from solutions containing 70 gil Pb++ and 90 g/l H2SiF6 using a lead cathode, Pb02-coated titanium anodes at 28° C, and a current density of 1.6 A/dm2. Current efficiencies approaching 92 pct were obtained. Accessory minerals such as cobalt and nickel were separated into purification residues and liquor.

Jan 1, 1982

By Warren E. Morrison

The continuing high-level performance of the domestic mineral and mineral fuels industries during 1966 was sustained by the longest business upturn in the Nation's history. Spurred by consumer demand at home and the defense production requirements of the Viet-Nam war, the rising trend of economic activity during the year was reflected in the upward movements of the major economic indicators. At yearend the gross national product (GNP), representing the value of all goods and services produced, stood at $740 billion, $58 billion greater than in 1965. Corrected for price changes, the real value of GNP in terms of 1958 dollars was $648 billion and represented an annual increase in economic activity of 5.4 percent. Some 74 million persons were employed during the year out of a total population of 196.8 million, while unemployment fell below 4 percent. The Federal Reserve Index of Industrial Production averaged 156 for 1966, up 13 points from the previous year. However a jarring note in the 1966 expansion, and one which affected the mineral industries in particular, was the increasing pressure on prices and the threat of inflation. From 1961-65 economic growth was facilitated by relatively stable wages and prices and only mild inflation. During the period average wholesale prices hardly moved while average consumer prices rose only about I percent per year. But this long run of relative price stability ended during 1966 when consumer prices rose 2.9 percent and wholesale prices were up 3.2 percent from the previous year.

Jan 1, 1967

By Nicholas Kyriazi, John P. Shubilla

The National Institute for Occupational Safety and Health, National Personal Protective Technology Laboratory, has undertaken a study to determine how well self-contained self-rescuers (SCSRs), deployed in accordance with Federal regulations (30 CFR 75.1714), hold up in the underground environment with regard to both physical damage and aging. This report presents findings regarding laboratory-tested SCSRs in the seventh phase of testing from May 1999 to August 2000. The SCSRs were tested on human subjects and on a breathing and metabolic simulator. The results indicate that most of the apparatus, if they pass their approved inspection criteria, perform satisfactorily. The deployed CSE SR-100s, however, exhibited significantly higher inhaled carbon dioxide (CO2) levels than new units, as they did in the previous two phases. Several Draeger OXY K-Pluses that rattled when shaken were found to have potassium superoxide (KO2) particles throughout the breathing circuit, including the mouthpiece. Draeger investigated the problem and developed a shake test to detect damaged units. The durations of new Ocenco M-20s were statistically significantly longer than those of deployed units, although only by 2 min.

Jan 3, 2002

By R. M. Santmyers

This paper represents one of a series of digests of foreign mining legislation that is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries . This interpretation of the mining legislation of Tunisia was prepared from a copy ( in French ) of the Mining Decree of Tunisia promulgated December 29 , 1913 , by the Resident General of France in Tunisia and effective January 1 , 1914. It is released subject to correction and amplification , if necessary , by the proper American diplomatic and consular officers , to whom it will be referred through the courtesy of the Department of State .

Mar 1, 1933

By James H. Aase

Selected glacial lake clay deposits in Minnesota were sampled, tested, and evaluated to determine their suitability for use as a bonding agent in iron ore pellet manufacturing. Preliminary tests conducted on clay samples obtained from five ancient glacial lake basins identified the clays in the Lake Agassiz glacial lake basin near Cook, Minn., as having the greatest bonding potential. An auger drilling program was conducted to obtain substantial quantities of representative material for detailed testing. The drilling indicated the presence of large clay reserves in excess of 500 million tons within the 12-square-mile area investigated. Bench scale tests indicated that the bonding properties of Cook area clays, when activated with relatively small quantities of sodium carbonate monohydrate (Na2C03?H2O), imparted excellent strength characteristics to iron ore pellets. Larger scale continuous pelletizing tests were made to confirm the bench scale results. These tests indicated that use of 1 percent activated clay alone as binder gave the iron ore pellets an overall strength slightly lower than with 0.75 percent bentonite, considered the industry standard. Use of 0.5 percent activated clay plus 0.5 percent bentonite produced better pellet strength qualities than use of 0.75 percent bentonite alone, without increasing the silica plus alumina content. The data from both bench scale and larger scale continuous tests suggest that the Cook, Minn., clays can be utilized after activation either alone or in combination with bentonite at an economic advantage over present pelletizing practice with bentonite.

Jan 1, 1968

By Kenneth C. Stewart

This contract was directed toward a study of the attenuating properties of earmuffs as worn by miners. Two attenuation measurement procedures were utilized. Human subjects were tested in a diffuse sound field according to threshold shift procedures recommended by the American National Standards Institute and a physical measurement procedure was accomplished in the same diffuse field on the same human subjects with microphones placed simultaneously on the inside and outside of the muffs. All measurements were obtained in one third octave of random noise. The results of the study indicated that physical and psychophysical attenuation measurements are in essential agreement at frequencies from 125 Hz to 2 KHz. Above 2 KHz the psychophysical measurement demonstrates larger amounts of attenuation than the physical measurement. The difference in attenuation ranged from approximately 7.0 dB to 9.0 dB at frequencies of 4 KHz and above. A possible explanation for the observed differences in attenuation has been presented.

Jan 1, 1980