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By D. Robert Weir, M. J. H. Ruscoe, R. M. Berezowsky, M. A. Clegg

The metallurgical processing involved in the produc-tion of the new Canadian one dollar coin is reviewed starting with the hydrometallurgical production of pure nickel powder, followed by the powder metallurgy process for the production of nickel strip and coinage blanks, and concluding with the Aureate bronze electroplating and heat treatment procedure. Coinage requirements are then reviewed with regard to economic, public acceptance, and service requirements. Finally the properties of Aureate nickel coinage are presented in the light of the many and varied coinage requirements, and it is concluded that the new Canadian dollar coin exceeds the requirements admirably.

Jan 1, 1990

By Henry Kreisinger, WALTER T. RAY

This preliminary bulletin was written as the first of a series of several on the significance of drafts in steam-boiler practice, the succeeding bulletins to be along the same lines but of a more advanced character. The conclusions arrived at are tentative, and are the result of a study of one of the many problems growing out of a general plan of the United States Government to increase the efficiency with which the coals of the country are being used. Greater efficiency requires better boiler and furnace design. The experimental study of drafts on which the conclusions presented in this bulletin are based formed part of the fuel-testing investigations that were carried on by the technologic branch of the United States Geological Survey and have been transferred to the Bureau of Mines. The experiments made seem to indicate that it is possible to double or treble the capacity of a plant without making any radical changes the furnaces and boilers. These increases require about double and treble the quantities of air to be put through the fuel beds and boilers. It also seems probable that rebafHing the boilers will often permit the capacity to be doubled or trebled, while still getting more steam than formerly per pound of coal for uses outside the boiler room. These experiments were undertaken with the object of clarifying ideas concerning the passage of air through fuel beds and boilers. Measured weights of air were passed through two beds of lead shot, series, one of which remained always the same and represented a boiler; the other being varied as to size of shot and depth of bed, and representing a fuel bed. Careful observations were made of the weight of air passing through the beds per minute. All data were plotted in many charts, so as to permit the study of them from several points of view. A number of laws were deduced bearing on the relative amounts of power required to force air through fuel beds of various thicknesses, composed of various sizes of coal, and through boilers of various lengths and areas of gas passages. An important part of the discussion relates to an increase in the capacity of boilers by increasing the amount of power applied to pressure and exhausting fans and thus forcing several times as much air through the fuel beds and boilers. may be possible, as a result of these investigations, to raise the rate of working the boiler heating surface to three or even four times its present value. Such an increase would undoubtedly mean new designs of grates, stokers, furnaces, and boilers, especially fitted for high rates of working. Fan equipments designed to supply three or four times as much air under several times the pressure would be provided with more efficient engines, thus giving an additional factor favoring high-capacity working. It must be borne in mind, as stated above, that the results are tentative. It will cost money to force gases at high speeds through fuel beds and boilers, and there will soon be pressing need of such quantitative data as will enable the largest possible part of the energy imparted by the fans to be advantageously utilized. We desire, to thank our superiors, especially Messrs. L. P. Breckenridge and D. T. Randall, for their helpful criticism and suggestions.

Jan 1, 1911

By K. Leutwyler, H. L. Bigelow

Jan 1, 1966

By F. A. Seward

A1though the expanding Eltran1 configuration has been used in induced polarization exploration for several years, there has been little application of this method to straight resistivity problems. A comparison of results of resistivity exploration by this technique versus those obtained from Wenner configuration surveys reveals a number of advantages in interpretative resolution as well as in field operation. The application of electrical resistivity to ground-water exploration is well known.= In the past a major portion of this work has been accomplished by use of one or more variations of a technique employing the Wenner3 electrode configuration. With the introduction of the frequency domain technique of induced polarization measurements, used primarily in the exploration for disseminated sulfide deposits, there arose the need for an electrode configuration by which potentials could be measured externally to the current electrode spread in order to minimize coupling between current sending and potential receiving circuits. It was also deemed desirable that the configuration would provide information laterally along profile as well as with depth. To reach these objectives the expanding dipole-dipole configuration (which probably first was used in the electrical transient method of exploration and from which the name 'Eltran' was derived) has been adapted to induced polarization exploration. The author has successfully applied the same techniques

Jan 1, 1963

By Cory G. Rice

A significant portion of the piling industry has long felt relying on soil setup to gain the required capacity is a complexity that would rather not be dealt with. Instead, the pile are driven to the required capacity on the initial drive and the potential gain of capacity due to soil setup is simply considered an added bonus or safety factor. There appears to be an attitude that if one did not put in the energy required to develop the full capacity on the initial drive, then one should not expect to gain anything from Mother Nature for free. However, substantial savings in time and materials can be realized by properly accounting for setup. This paper will show the impacts and ramifications this rationale can have on required labor and material costs and illustrate a case history with significant soil setup and the savings realized on a project currently being constructed.

Jan 1, 1992

By P. R. Thomas

The Bureau of Mines determined the costs associated with the production of chromium, in the form of chromite and high-carbon ferrochomium, from the demonstated resources of 10 market economy nations. The analyses evaluated the relative geologic and economic position of these chromite resources contained within 80 producing or potential mining operations. This report presents cost evaluations of a demonstrated resource of chromite, contained within the nations studied, of appoximately 1.2 billion metric tons (t). Of this total, 70 pct is contained within the southern African nations of Zimbabwe and the Republic of South Africa. The majority of current chromium mining and smelting capacity is contained within these two countries as well. India and the Philippines have recently demonstrated greatly increased chromite resources and hold the most promise for expanding both chomite and ferrochromium production outside southern Africa. Their demonstrated resources represent approximately 7 and 16 pet, respectively, of the cost evaluated total tonnage. Chromite resources, on an identified or hypothetical basis worldwide, are highly concentrated within Zimbabwe and South Africa, with these two nations containing in excess of 95 pet of the total. Given the present market structure, a majority of chromium contained within the demonstrated chromite resources of the nations studied is economically recoverable; but from a long-term resource and economic perspective, South Africa should inceasingly dominate the markets for both chromite and high-carbon ferrochromium. In addition, it is anticipated that an increasing percentage of chromium traded on the world market in the future will be in the form of high-carbon ferrochromium as opposed to chromite, as this additional processing stage continues to relocate from the industrial nations that account for a majority of chromium consumption to those nations that mine chromite.

Jan 1, 1984

By Alfred H. Bell

Drilling activity increased in Illinois in 1935. There were 34 com-pletions as compared with 26 in 1934 and 18 wells were drilling at the end of 1935. Some large blocks of acreage were leased in Marion and Clay counties near the central part of the Illinois structural basin. Production of oil in the state totaled 4,305,000 bbl., a decrease of 4 per cent from that of 1934 There was some curtailment of production in the early part of 1935 but none after April 30 as shown in the following table. Percentage Pro-duced of Potential ProductioN (USING September 1934 Period as BaSis) Jan. .l-Feb. 20............................................ 79 Feb. 21-Feb. 25............................................ 85 Feb. 26-Feb. 38............................................ 79 Mar. 1-Mar. 11............................................ 85 Mar. 12-Mar. 31............................................ 100 Apr. 1-Apr. 9.......................................... 80 Apr. 10-Apr. 30............................................ 86 May 1-Dec. 31........................................... 100 This is equivalent to an average curtailment throughout the year of 5 per cent. The price of Illinois crude oil at the wells remained constant during 1935 at $1.13 per barrel. A small amount of oil was sold at a 1ower price, notably from the Dupo field, but to arrive at a value for the state's production there would be little error in assuming an average price of 81.13, giving a total value of $4,864,465. The following table shows production in Illinois by moths in 1935, according to the U.S. Bureau of Mines. Jan............. 332,000 May.......... 382,000 Sept ,............. 370,000 Feb............. 295,000 June. ........... 858,000 Oct.............. 391,000 Mar............ 370,000 July............ 377,000 Nov............. 369,000 April............ 338,000 Aug............. 379,000 Dec............ 344,000

Jan 1, 1936

By Alfred H. Bell

Drilling activity increased in Illinois in 1935. There were 34 com-pletions as compared with 26 in 1934 and 18 wells were drilling at the end of 1935. Some large blocks of acreage were leased in Marion and Clay counties near the central part of the Illinois structural basin. Production of oil in the state totaled 4,305,000 bbl., a decrease of 4 per cent from that of 1934 There was some curtailment of production in the early part of 1935 but none after April 30 as shown in the following table. Percentage Pro-duced of Potential ProductioN (USING September 1934 Period as BaSis) Jan. .l-Feb. 20............................................ 79 Feb. 21-Feb. 25............................................ 85 Feb. 26-Feb. 38............................................ 79 Mar. 1-Mar. 11............................................ 85 Mar. 12-Mar. 31............................................ 100 Apr. 1-Apr. 9.......................................... 80 Apr. 10-Apr. 30............................................ 86 May 1-Dec. 31........................................... 100 This is equivalent to an average curtailment throughout the year of 5 per cent. The price of Illinois crude oil at the wells remained constant during 1935 at $1.13 per barrel. A small amount of oil was sold at a 1ower price, notably from the Dupo field, but to arrive at a value for the state's production there would be little error in assuming an average price of 81.13, giving a total value of $4,864,465. The following table shows production in Illinois by moths in 1935, according to the U.S. Bureau of Mines. Jan............. 332,000 May.......... 382,000 Sept ,............. 370,000 Feb............. 295,000 June. ........... 858,000 Oct.............. 391,000 Mar............ 370,000 July............ 377,000 Nov............. 369,000 April............ 338,000 Aug............. 379,000 Dec............ 344,000

Jan 1, 1936

By R. K. Guthrie, H. B. Hill

"INTRODUCTION The Rodessa oil field in Marion and Cass Counties, Tex., Miller County, Ark., and Caddo Parish, La., was discovered in August 1930, when a well drilled to a depth of 5,506 feet in Caddo Parish, close to the surface trace of the Rodessa fault, produced gas in commercial quantities. During the next 5 years 21 gas wells were drilled, and a large reserve of natural gas was developed in the high part of the Rodessa structure underlying the Massive Anhydrite member of the Glen Rose formation.In July 1935 oil was discovered on the flank of the structure when a well drilled to 6,048 feet also in Caddo Parish, was completed as an oil well. The discovery of oil in the Rodessa structure initiated art intensive development program of more than usual interest to geologists, engineers, and operators in the petroleum and natural-gas industry. The complex nature of the different reservoirs, the large volume of ""free"" gas under high pressures and temperatures in the upper part of the reservoirs, and the high gas:oil ratios of some of the wells during the early production of oil presented many problems the solution of which taxed the ingenuity of those responsible for the development and exploitation of the Rodessa field.Early waste of gas and resultant dissipation of reservoir energy led to State intervention, which brought about effective regulation of the quantity of gas blown to the air. Oil production from wells producing more than 2.000 cubic feet of gas per barrel of oil was restricted, and oil allowables generally were based equally upon acreage and upon reservoir pressures. Consequently, oil-production statistics of the field are closely associated with gas:oil ratios and reservoir pressures.The primary object of this report is to present factual and statistical data on well performance in the Rodessa field and to show established trends under certain operating methods and practices in high-pressure gaseous reservoirs, which have been carefully developed and outlined by modern technique and exploited under close engineering supervision.The large size of the Rodessa field, it’s fairly well defined gas caps, and a somewhat definite water table in a part- of the oil- and gas-producing region are of special interest and importance in a study of the fluid and energy relationships in reservoirs. Consequently, the results of much of the authors' work in collecting and compiling date are presented in the form of tables, maps and cross sections to show the relative thicknesses of the different oil-and gas-producing members and their permeability and porosity relationships, and, when possible, the variations in stratigraphy are exhibited in cross sections. Results of a detailed analysis of cores from a number of wells also are presented in tabular and graphic form."

Aug 1, 1943

By P. A. Riveros, J. Binvignat, V. M. McNamara, D. Koren

The recovery of cyanide from a gold mill solution containing high levels of copper (400 mg/L to 900 mg/L) using the AVR process was evaluated. It was determined that acidification to pH 2 to 3 provides a suitable balance between HCN generation, copper precipitation and acid consumption. A short pilot plant campaign showed that ~75% of the feed WAD cyanide was recovered while the remainder precipitated along with copper upon acidification. The acid consumption averaged 3.5 g H2SO4 per litre of solution. The copper precipitate, consisting mostly of CuCN and CuSCN, was readily separated from the solution by gravity. The volatilization of HCN in countercurrent packed columns averaged 98.7% efficiency. Reabsorption of HCN was practically 100% in NaOH solutions and slightly lower in a lime slurry. Basic volatilizer design parameters applicable to a large-scale operation were determined, including the Henry’s Law constant and the mass transfer coefficient of HCN gas.

Jan 1, 1998

By F. F. Aplan

Though over 100 minerals are known to contain the rare earth (RE) or lanthanide elements, only a few provide the bulk of the world's source of these elements. The principal RE-containing mineral, monazite [(Ce,La,Th,Y)PO4], is recovered by gravity, magnetic, electrostatic and flotation concentration methods, while the other important source mineral, bastnasite [CeFC03], is concentrated by flotation. The processing of the lesser important source minerals is discussed, as is the recovery of the lanthanides from apatite [Ca5(P04)3(F,OH)] where the rare earth elements are present from trace amounts to over 10% as the mixed oxides.

Jan 1, 1989

By Marcella Gautê Cavalcante Xavier

A presente proposta tem por objetivo desenvolver uma análise experimental da liga hipereutética Sn-0,5%Ni solidificada unidirecionalmente em regime transitório de fluxo de calor contra chapa molde de cobre. A liga foi avaliada quanto a sua microestrutura bruta de fusão e suas respectivas correlações com os parâmetros térmicos (velocidade da frente eutética -VE e taxa de resfriamento eutética -?E) e propriedades mecânicas. Os resultados mostram que a morfologia microestrutural predominante é composta por células ricas em estanho (β-Sn) circundadas por mistura eutética Sn+intermetálico tipo NiSn. Uma transição microestrutural foi observada entre as posições 15mm (?E=1,7°C/s) e 30mm (?E=1,1°C/s), de célula regular (CR)?célula tipo placa (CTP). Notou-se ainda a presença de intermetálicos primários NiSn distribuídos ao longo da matriz nas posições iniciais do lingote. Valores superiores de limite de resistência à tração (σu=26 MPa) e limite de escoamento (σy=21 MPa) foram encontrados para a posição 6mm a partir da base refrigerada do lingote, podendo estar relacionados com a estrutura celular mais refinada e também com a presença dos intermetálicos primários NiSn. O alongamento específico (?) comportou-se de maneira inversa, visto que as estruturas mais grosseiras (CTP) e a ausência de intermetálicos primários são responsáveis por facilitar a deformação plástica na estrutura da liga Sn-0,5%Ni, aumentando seu nível de ductilidade.

Oct 30, 2017

The STATE MINERAL SUMMARIES publication provides estimated data and summaries of mineral activities at the State level for 1991. Most of the estimates are based on nine months data. Individual State summaries are published separately as State Mineral Industry Surveys and copies can be obtained from the appropriate State mineral officer or Bureau field office specified in each State summary.

Jan 1, 1992

By D. K. MACKAY

The production of oil and gas in Arkansas is confined to two distinct and widely separated regions of the state; namely: (1) South Arkansas in the Gulf coastal plain, where 49 fields-many containing two or more reservoirs or pools-yield oil, condensate and gas from beds in the Cretaceous and Jurassic, and (2) Northwest Arkansas, a part of the Arkansas Valley, where only dry gas is produced in 21 fields from sandstones of Pennsylvanian age. Exploration during the year 1945 centered largely in these two producing regions, but some of the geophysical surveys were made and wildcat drilling was done a considerable distance outside these regions.

Jan 1, 1946

By Jesús E. Gómez

This work is a continuation of a paper presented in the 32nd DFI Annual Conference, Colorado 2007, titled ?Hollow Core Bar Micropiles - Design parameters interpreted from 260 load tests.? The first paper presented the results of the verification and proof tests performed for the retrofit of two bridges with hollow core bars that used 260 micropiles. It included an interpretation of the unit bond values in the different soils where micropiles were installed. Recently two additional bridges within the same geological environment were also retrofitted using 144 hollow core micropiles. This paper includes the interpretation of the additional data from the proof tests performed and refines recommended values for design of hollow core bar micropiles in soils similar to those encountered in these two projects. The authors believe that the data collected will significantly add to the relatively small existing database on micropile tests and may also be useful during implementation of the LRFD design methodology.

Jan 1, 2008

By J. G. George

A brief review of the silver industry is presented to set the stage for the analysis of the distribution of silver production by source from various types of mines in Canada and of the changing relationship between the total output of silver and the total output of base metals. The decline in the average grade of the Canadian mines is also discussed and a trend for the future is proposed. The report then examines in broader aspects the world primary silver production and concludes, in the section on outlook, that the effective supply in primary silver will grow at a rate significantly lower than the growth rate expected for base metals. A cumulative deficit of some 900 million ounces is projected for the period 1975-1980 and a further deficit of some 1,100 million ounces if projected for the 1980-to-1985 period.

Jan 1, 1977

By S. K. Bradford

(Pittsburg Meeting, March, 1910.) FOR years past I have traveled in quest of promising mining-properties, over almost impassable mountain-trails to remote places in the mining-regions, usually, many miles from an assay-office. If, upon examination, the formation and the ore-deposit appeared favorable, a quick determination of the value of my samples was necessary, in order that I might take intelligent action with reference to the acquisition of the property. A journey with my samples to civilized regions often meant weeks of delay, and perhaps loss of opportunity. How many, under similar circumstances, have returned with their assay-results from such a journey, only to find that some audacious speculator had " optioned" the property ! True, a first payment could have been made and the chances taken on the results; but experience has taught that rich-looking ore is not of necessity valuable. Personally, I would not hazard a ten-dollar bill on any property without first determining by assay the value of the ore. To carry the usual complete assay-paraphernalia over such mountain-trails was impracticable by reason of the loss of time involved, the great expense of transportation (charged according to weight), and the fact that a few such trips would almost certainly wreck the outfit. For these reasons I began a process of elimination and substitution which finally enabled me to carry, in an ordinary 26-in. valise, sufficient apparatus and supplies for, say, 100 assays of adequate commercial accuracy. My final outfit was as follows: APPARATUS. Small hammer; steel mortar (2.5 in. wide, 3 in. high, with stand sawed off flat, so that it can be used as an anvil and for

Jan 1, 1911

By J. J. Forbes

Problems connected with the incidence, effects, determination, and control of dusts are still much before the public, although more information is available to the layman than when Bulletin 400, of which this publication is a revision,5 was issued in 1937. Bulletin 400 attempted to assemble information in convenient form on various phases of the dust problem, largely in the mining and allied industries. This revision includes data that have accumulated since 1937 and some that appeared previous thereto but were not available to the authors at that time. The literature on this subject is so voluminous that no attempt has been made to include all published material or all types of dust diseases, but only to assemble some of the more outstanding data on several aspects of the subject.

Jan 1, 1950

By Alan K. Burton

Massive increases in the productive capability of open pit nines after World. War II were in a large part made possible by the introduction of ever larger trucks and the supply of a seemingly bottomless ocean of inexpensive and readily accessible oil. Over a period of about 25 years, a variety of technological developments permitted a tenfold truck payload increase, from about 32 tonnes (35 tons) to 320 tonnes (350 tons). There is no, doubt that this was a remarkable achievement resulting in impressive benefits of scale as well as the ability to control what would otherwise have become an intolerable traffic congestion problem in today's large open pit mines. It became fashionable and economically possible during this time to mine large quantities of low grade material and to tolerate very high stripping ratios. As tine has gone by and as easier to get at and higher grade deposits have been depleted, ore grades have tended to decline while stripping ratios have increased. The alternative to reduced revenues has been an ever increasing demand to step up production which in turn has led to a continuing demand for ever larger and larger trucks. While a larger truck has had the effect of reducing the cost of the operator per unit of material moved and of reducing traffic congestion, it has not specifically addressed the subject of fuel cost.

Jan 1, 1981

The rocks of Waihi and the surrounding district are almost entirely rhyolitic and ande5itic in character. Sedimentary rocks, with the exception of some surface deposits of clay loosely compacted conglomerate, etc., and one or two thin and broken beds of a very poor lignite, occasionally changed by igneous agencies into a bituminous coal, are almost absent. In the shafts sunk by the Waihi and Grand Junction companies outside the outcropping andesitic area of the Martha Hill, more than one old surface or lake bottom has been passed through. At these points layers of sand, consolidated volcanic mud and tuff, accompanied by numerous broken fragments of imperfectly silicified wood have been enccuntered, but these occurrences may, for the purpose of this paper, be neglected.The youngest rock of the district are rhyolites, probably of Pliocene age. At least three distinct classes of rhyolitic lava, each possessing features of unusual interest, may be made out. None of these, however, is gold-bearing. The youngest flow, a light-coloured, fine-grained rock, is remarkable owing to its enclosing at times fragments of carbonised wood, varying in size from mere specks up to quite large pieces of almost pure charcoal. Rhyolitic tuff is also met with. The rhyolites cover a large extent of nearly flat country east, south, and west of Waibi, here and there rising into barren, stony hills.Below the rhyolites, geologically speaking, but for the most part. forming hills which bound the rhyolitic plain, or rise out of it as isolated patches, come ahdesites of older...

Jan 1, 1902