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By R. P. Moran, B. C. Lewis

The objective of this article is to discuss the fundamentals for determining the value of a limestone reserve or operation. The general step-by-step procedure, while prudent, is subject to the various site-specific issues that influence the valuation calculation. The most common methods for determining fair market value of mining lands are: comparable sales, operational analysis, and royalty analysis. An overview of typical eastern limestone mines (both quarries and underground) is presented. Specifically, properties in West Virginia and Alabama are reviewed and the sample methodologies and valuation calculations are presented.

Jan 1, 1991

By William R. Wayment

The objective of this investigation was to obtain data on friction-head losses of sand slurries during their transport in pipelines. The data ultimately will be used in designing hydraulic transport systems. Information that was incidental to the primary objective was gathered on degradation, changed percolation characteristics, and critical velocities of the slurries~ Tests were made in a closed-circuit pilot plant, with one type of tailing, through horizontal 2-, 3-, and 4-inch-pipe test sections at various pulp densities and flow velocities. Tests were made in a closed-circuit pilot plant, with one type of tailing, through horizontal 2-, 3-, and 4-inch-pipe test sections at various pulp densities and flow velocities. Approximately 2,000 tests were run in the pilot plant. The ranges of flow velocities used in the experiment were 2.8 to 19 f.p.s. in the 2-inch line, 4 to 14.5 f.p.s. in the 3-inch line, and 4 to 11 f.p.s. in the 4-inch line. Velocities were varied in increments of 0.5 f.p.s. through the entire velocity range in each pipe size. Densities were varied in 3-percent increments from 40 to 70 percent solids by weight except for one series of tests in the 2-inch line; in this series, densities were varied in 5-percent increments from 5 to 65 percent solids by weight.

Jan 1, 1962

By W. W. Mein

IN March 1949 the Calaveras Cement Co. was sued by five landowners whose properties are located in the vicinity of the plant. These landowners—all of them cattle ranchers—sued for dust damages of $120,338 and for an injunction preventing the company from casting dust upon their properties in injurious quantities. The issue was split, the jury deciding the amount of damages and the court handling the injunction features. The action came to trial before a jury in April of that year and resulted in damages being awarded in the amount of $7,508. A month later the court issued its injunction requiring recovery of stack dust to an 87 pct minimum. The Calaveras plant, shown in Fig. 1, is located three miles from San Andreas in the heart of the Mother Lode country, about 45 miles east of Stockton, Calif. Since it is in a small town, the company's responsibilities to its employees and to the community are different from those of plants located in large centers of population. Construction of the plant was begun in 1925, and production was started the following year. Standard gray Portland cement as well as several specialty cements are produced. Production facilities have been continually enlarged so that the present capacity is more than double what it was 25 years, ago. The most important item in the company's expansion program was the purchase in 1945 of an 11 ft 3 in. x 360 ft Allis-Chalmers kiln which had been declared surplus by the Defense Plant Corp. The company is now able to produce about 2,500,000 bbl of cement a year, and employment at the plant is approximately 300. The production of cement has always involved a dust problem, solution of which has been attempted in a number of different ways. By far the most efficient method of catching dust discharge is electric precipitation. Soon after the company went into production in the 1920's, the landowners near the plant began complaining about dust discharge. The company settled the matter by paying them a total of $27,000 for dust damages incurred during the period from 1929 to 1938. In the latter year the two-unit Cot-trell Electric Precipitator shown in Fig. 2 was installed and collected over 85 pct of the dust resulting from operation of the two 11 ft 3 in. x 10 ft x 240 in. kilns. From 1938 until 1946 the landowners registered no objection and were apparently satisfied with that dust recovery. In 1946, however, the substantially higher production resulting from operation of the new kiln immediately overtaxed the facilities of the existing two-unit precipitator. In a short time claims for dust damages were again received from the landowners. The company informed them that because of postwar shortages it would take several years to install a new precipitator. The company stated that it intended to purchase an additional precipitator and offered in the meanwhile to pay the landowners a fair amount to cover their damages. This offer was rejected and the landowners filed suit in the Superior Court of Calaveras County asking for total damages of $120,-338 and for the injunction outlined above. Case for the Ranchers The attorneys for the plaintiffs produced three different types of witnesses: first, the landowners themselves and members of their families; second, other cattle raisers who were sympathetic to the plaintiffs; and third, several types of technical experts: veterinarians, soil chemists, and an aerial photographer. The testimony of these witnesses was designed to establish that the flue dust from the plant had not only damaged the land and the forage, but had also caused fluorine poisoning to their animals. By a combination of these causes, the plaintiffs attempted to prove substantial loss of profits.

Jan 1, 1952

By L. A. Haas

In this Bureau of Mines investigation, conditions were determined to form an iron sulfide adherent coating with a metallic golden luster on steel upon anaerobic heat treatment with sulfur. The sulfide formation rate was determined in the temperature range of 105° to 500° C with reaction times up to 68 hours. The optimum temperature and time to form an adhering decorative coating on mild steel was in the range of 105° C for about 70 hours to 285° C for 1 hour. The golden coating consisted of an inner layer of pyrrhotite and an outer layer of pyrite. At temperatures higher than about 300° C, the outer layer thickness decreased owing to the decomposition of pyrite to pyrrhotite.. Small quantities (<0.5 wt-pct) of petroleum oil accelerated the sulfide growth rate. The sulfide coating decreased the corrosion rate of steel in a neutral aqueous medium by a factor of two. The dissolution of pyrite in water was dependent on particle size and surface area with the flat pyrite coatings exhibiting the lowest dissolution rate.

Jan 1, 1974

By E P. Nelson, R Gutierrez, P W. Layer

The San JosT district in Patagonia comprises a number of epithermal precious metal quartz veins hosted by a Mesozoic volcanic sequence. New radiometric data indicates that upper Jurassic volcanism was closely followed by vein mineralisation in the lower Cretaceous. A structural model is discussed for the district at times of mineralization that may also apply on a regional scale and other mineralised districts in Patagonia. An&nbsp;EXTENDED ABSTRACT&nbsp;is available for download. A full-length paper was not&nbsp;prepared for this presentation.

Jan 1, 2008

Tailings embankments can develop a high phreatic surface if the original design for the embankment does not include drainage facilities or if existing drainage facilities become ineffective. Subsequent raises can develop a seepage surface due to a high phreatic surface that can lead to stability problems. The U. S. Bureau of Mines amended contract J0100013 to initiate this study of horizontal drains in tailings embankments. This study developed a technique for determining the length of and spacing between parallel drains through the use of the finite element model UNSAT2. The analysis is based on the combined output of a vertical planar mesh and a horizontal planar mesh. The slot opening in the drain pipe and the length of the perforated section are determined from an analogy to water well design. The pipe diameter and gradient can be determined from Manning&apos;s equation. To the authors&apos; knowledge, this is the first attempt at horizontal drain design using a finite element model. Additional research is recommended in this area.

Jan 1, 1982

By D. R. Parrish, T. M. Geffen, R. A. Morse, W. W. Owens

Laboratory studies of several factors affecting measurements of relative permeability were made using the three-section plastic-covered core technique. Results show that the core assembly, properly constructed, will perform as a single unit, and that the testing technique will, under suitable conditions of pressure gradient, gas expansion, and migration of partial water saturation, permit measurement of flow characteristics not affected by technique. Wettability equilibrium is readily established in cores exhibiting strong wetting preference to water or oil when initially saturated with water. Laboratory tests must be conducted so that saturation changes represent those that occur in the reservoir. Immediate implications of saturation history are (1:) that the possibility exists of increasing the displacement efficiency of solution gas drive reservoirs over the natural process, and (2) residual gas saturations following water flooding in gas or gas condensate reservoirs will be 15 to 50 per cent pore space rather than 1 to 11 per cent as generally believed. INTRODUCTION Solutions of petroleum reservoir problems pertaining to production performance require the use of true relative permeability characteristics. &apos;This relationship of fluid conductivity and saturation has been obtained by reservoir engineers in four ways, namely: 1. From past gross reservoir performance and the extrapolation of this data based on experience,1,2 2. By using published fluid flow relationships obtained in laboratory studies on general type porous materials,3, 4, 5 3. By attempting a mathematical derivation of flow behavior," using some experimentally obtained characteristics of reservoir rocks, and 4. By laboratory flow tests using representative rock samples of a reservoir. The first three methods listed above have shortcomings which make their use limited or questionable. Production characteristics of only certain processes are obtained from field data and these are not available at the beginning of a reservoir&apos;s producing life, at which time they are desirable. It is fortuitous if general fluid flow characteristics obtained experimentally have accurate application to specific field problems. Also, it is felt that at this time there is not sufficient knowledge of the flow behavior of oil, water, and gas in porous materials to enable applicable analytical description of this to be made based on other measured rock characteristics. Measurement of relative permeability in the laboratory offers the only direct method subject to adequate checking for determination of flow characteristics applicable to field problems. Primarily, this paper deals with laboratory experiments to establish the effects of several factors on the measurement of relative permeability and the practical significance of this knowledge. Laboratory flow tests are essentially model studies; the gross reservoir being represented by a small rock sample. It is necessary to simulate in experiments all the factors of importance which influence flow in the reservoir, as well a.; to eliminate effects peculiar to the model studied to assure measurement of valid flow behavior. Factors which affect the measurement and behavior of fluid flow in porous materials have been studied by other investigators.3,7,8,9,10,11 This analysis is not intended to evaluate fully all factors involved, but to establish first the validity of measurements by the technique used and then study flow behavior under various conditions. The studies reported are as follows: 1. Effects of pressure gradient, 2. Effects of gas expansion in tests conducted at near atmospheric pressure, 3. Effects of migration of a partial water saturation in oil-gas-water systems, 4. Effects If wettability characteristics of the system. and 5. Effects of the fluid saturation history. The first three are important only in laboratory measure-

Jan 1, 1951

Beneficiation of Nickel Lateritic Ore from Montes Claros de Goißs, Brazil Beneficiation is a key factor for both technical and economical aspects of industrial processing of nickel lateritic ores. A combination of comminution, classification and concentration stages are usually used to upgrade the metallurgical plant feed, thus resulting in both capital and operating cost reductions. This paper describes the testwork conducted on Montes Claros nickel lateritic ore in order to investigate the potential for upgrading. A comprehensive laboratory testing program included crushing, scrubbing, screening, grinding, gravity separation and attritioning, for both saprolitic and limonitic ore types from the Montes Claros deposit. The results indicated a clear potential for such an upgrade, which was later validated in a pilot plant program.

Sep 13, 2010

By E. C. Harder

J. T. SINGEWALD, JR., Baltimore, Md.-I might say a word further in regard to the Miguel-Burnier district. I am sorry Mr. Harder is not here. I had hoped to be able to ask him a few questions in regard to some of the features of those deposits. This Miguel-Burnier district is the other district that I referred to that lies in the State of Minas Geraes. The interpretation that Mr. Harder gives to, these deposits is the same as that given by Harder&apos; and Chamberlin in a previous paper, and that is that they consist of lenticular deposits of sedimentary origin in a series of rocks that also include lenses of limestone, but they seem to think that the manganese ores occur at a definite horizon and at a horizon different from the limestone. We found that the manganese ores occur at several horizons, as also do the limestone lenses, and the limestone masses are of the same shape as the manganese orebodies, so that our own feeling was that these manganese ores simply represent concentrations within the zone of oxidation formed as. a result of decomposition and replacement of this limestone. To the east of Miguel-Burnier there is a big bend in the railroad which cuts through, at right angles to the strike, this series of rocks. Here is shown very well both the local character of the limestone lenses and the local character of the manganese lenses in that, though the distance across the bend is only a couple of hundred yards, the limestone and. ,manganese lenses do not match up at all, and it also shows plainly that both occur at more than one horizon.. Consequently there is no reason why the manganese ore could not represent alterations of this limestone. The mine workings do not as yet give very definite information on this point in that they are all comparatively shallow and within what would be the zone of oxidation so that what they will grade into below that depth, we do not know. On the other hand, the character of the ore suggests that it may, represent such -a product in the zone of oxidation in that it tends to be quite earthy; whereas, if the manganese had been there originally as such it would have undergone the same metamorphism that the other rocks have undergone and one would have expected that it would have been converted into a hard manganese ore that would today stand out pretty much as do the iron ores of that same region and not have the soft, earthy texture which is a prevailing characteristic.

Jan 4, 1917

By Fookes R. A, Gardner K. J, Gravitis V. L, Watt J. S, Steffner E. J

Two radioisotope techniques suitable for the rapid laboratory determination of the ash content of coal have been tested ou unwashed coal samples from four Australian coal seams. In one techniqne, measurements of backscattered 238Pu L X-rays and iron K X-rays from finely ground coal samples have been combined to determine ash content in uuwashed coals to &#177;0.5 weight per ce111 ash (ls) for three seams and 0.9 weight per cent ash for the fourth.The second technique, which involves measurements of the transmission by the coal of narrow beams of 241Am 60 keV and 123Ba 356 keV ? rays, requires less sample preparat ion. The ash was determined to within the range of 0.8 to 2.6 weight per cent for the four seams (unwashed coal). For washed coals, errors are expected to be &lt; &#177;0.5 weight per cent ash.

Jan 1, 1982

By J. D. Pelletier

SAN MANUEL orebody is a disseminated copper deposit in quartz monzonite, monzonite porphyry, and diabase. Quartz monzonite, which is Pre-Cambrian1 in age, is exposed in an area including No. 1 and No. 4 shafts and extending about 2400 ft southeast from No. 1 shaft. It is also exposed in the bottom of No. 2 shaft and in a zone roughly 500 to 1200 ft southeast of No. 2 shaft having its long dimension along a northeast-southwest axis. Churn drilling has shown all these exposures to be parts of a contiguous mass of quartz monzonite lying within and beneath the ore zone.

Jan 7, 1957

By H. K. Shearer

Oil production in north Louisiana in 1938 was 28,442,910 bbl., a decrease of 225,160 bbl., or less than 1 per cent, from 1937. The principal increases were at Cotton Valley, Lisbon and Zwolle. The greatest decrease was at Rodessa, with small normal declines in production of the old settled fields. Natural gas production from gas wells declined 15.9 per cent from 1937, but casinghead gas increased, so the decline in total production was only 6.9 per cent. Decline in completions was due to lack of proven areas for drilling, as well as price and marketing difficulties; and wildcat activity mas also less than in 1937. The increase in number of dry holes was due chiefly to shallow drilling in the old Caddo and Zwolle fields. Most important events in 1938 were the discovery of the Shreveport deep oil and gas field, extension of the Logansport gas-distillate field into Louisiana, development of oil production in the Bodeaw zone on the flanks of Cotton Valley, opening of deep gas-distillate production at Shongaloo, and completion of one well in a deeper horizon at Bluc Lake (Zwolle field). Geological Notes The deep drilling done in 1938 did not cause any important changes in geological correlation and nomenclature of the formations below the Upper or Gulf Cretaceous. The stratigraphic section of the Lower Cretaceous and deeper beds, with names used in the accompanying tables, as approved a year ago by the Shreveport Geological Society, is as follows:

Jan 1, 1939

By John Griffen

K. F. Tromp (Kerkrade, Holland)—Your assumption that the Dutch State Mines have lead in the development of heavy medium processes—the Barvoys, Loess, Driessen—is not correct. The credit should be given to a Dutch engineer Mr. deVooys, the inventor of the Barvoys process. deVooys started in 1932 in Hiickelhoven, a German but Dutch-owned mine, where he was a director. Several plants on the Continent as well as in Great Britain were erected. The State Mines started their first plant in 1937. They could not get that plant working satisfactorily and built another one. Their process made no headway, and up to 1946 there was only one plant installed, the one at their own pit. Since 1946 they started the cyclone process and only since that time have they been more active, though industrial cyclone washeries are still in their infancy. deVooys sold his patents to the Dutch State Mines in 1946 and this might have given you the impression that the pioneer work had been done by the Dutch State Mines. John Griffen (author&apos;s reply)—I wish to thank Mr. Tromp for giving the correct story on the development of heavy medium processes in Holland.

Jan 1, 1952

By O. Worku, J. H. Masliyah, Z. A. Zhou

ABSTRACT The viscosity of concentrated kaolinite or illite clay in aqueous suspensions was measured in the presence and absence of a small amount of montmorillonite (<1 wt%). To avoid solids settling and to increase the sensitivity of the suspension viscosity measurements, solids concentrations higher than 38 wt% were used. The pH of the suspensions and the concentration of calcium and bicarbonate ions were found to significantly impact the viscosity of the clay suspensions. The results showed a significant increase in the viscosity of kaolinite suspensions with the addition of as low as 0.25 wt% of montmorillonite on a solids weight basis. In addition to illustrating the role of water chemistry in modifying slurry rheological properties, our study demonstrated that viscosity measurement could be a simple, yet sensitive technique for determining the content of smectite clays, such as montmorillonite, in a complex mix of various types of clay.

Jan 1, 2012

By David, Levinger

THESE observations of the metal-working industries of Europe are based on a three months&apos; tour of eight countries of Europe, in which 75 industrial establishments were visited in England, France, Germany, Belgium, Holland, Italy, Austria and Switzerland during the summer of 1927. Since the Western Electric Co. is a large consumer of copper and brass, these industries were of particular interest and differences in practices were of keen interest to us.

Jan 1, 1928

By Luis de Montreul

El conocimiento de los controles mineralógicos, tipos de ocurrencias y otras características mineralógicas de los depósitos auríferos permite plantear una adecuada exploración geológica-minera y seleccionar un óptimo tratamiento metalúrgico. Por ello, se busca establecer la relación entro el oro y determinados minerales metálicos y no metálicos para obtener una mejor recuperación de este elemento valioso. En ese sentido, el presente texto presenta ejemplos de controles mineralógicos en seis yacimientos aurífero de cinco Fajas mineralizadas del Perú.

Jul 1, 1987

By Ray Light, Everett M. White

Numerous articles have been written about the coal miner ; he has been compared with brave men who have gone out to conquer some unknown hazard throughout the ages. Now, however, modern mining is no longer something to be avoided, but a vocation that anyone can be proud of, with remuneration equal to or above that of almost any industry. A concerted effort is being made each day by both the operators of most mines as well as the state and federal inspectors to see that coal mines are as safe or safer than work places in any other industry. How- ever, it is true that mine fires and explosions have occurred in the mining industry since its inception. One of the earliest accurate references to such an occurrence is found in the transactions of the Royal Society of London. In the Colliery Managers&apos; Handbook, 1898, Caleb Pamely writes of an explosion that occurred ,at Fatfield, England in August 1708, resulting in the deaths of 69 persons. He states: "Three of them, viz, two men and a woman, were blown quite up from the bottom of the shaft, fifty-seven fathoms deep, into the air, to a considerable distance from the mouth of the pit." It is interesting to note that women were employed ,as miners in England during that period. In the United States, the first record of coal mined was in 1702 by the Jamestown colonists. In 1786, about 20 years after Pittsburgh, PA was first settled, a charter was granted by William Penn to mine coal on the banks of the Monongahela River. Then in 1803, the first important coal company, the Lehigh Coal Co., was established. From this beginning, the mining industry continued to grow in importance and the first state mining law was formulated in 1870. The Pennsylvania state mining law was followed in 1873 by Ohio&apos;s, and in 1876 by Maryland&apos;s. A mine explosion at Avondale, PA in 1869 stimulated state legislatures to formulate these early laws. In 1907 near the town of Fairmont, WV, there were, within three days, two explosions resulting in a total of 597

Jan 1, 1981

By Fardy J. J

Abundance data are presented for a comprehensive range of elements in oil shale samples from deposits located in Queensland. The techniques of instrumental neutron activation analysis and spark source mass spectrometry were used to obtain concentration data for up to 50 trace elements in each shale. These techniques were supplemented by other spectrometric methods to obtain data for major, minor and some trace elements. Sixty-four elements were determined quantitatively. This comprehensive characterisation of oil shale samples from the major deposits in Australia provides inorganic abundance data not previously available. It also provides important background information for processing studies and the associated environmental aspects of shale oil production and waste disposal.

Jan 1, 1986

By R. L. Levens

The Underground Injection Control program was promulgated in 1981 by the U.S. Environmental Protection Agency under the provisions of the Safe Drinking Water Act. Placement of mine waste backfill underground is considered underground injection under the provisions of this program. A major issue is whether mine waste that is regulated as a contaminant source on the surface should be disposed of underground. The U.S. Bureau of Mines conducted research to investigate the impacts of mine waste sandfill on the quality of ground water. Analyses of water samples collected before and after contact with sandfill in a 10-year-old stope, as well as samples of the sandfill itself, were used to ascertain the influence of the sandfill after mine closure and subsequent flooding. Computer models supported the hypothesis that oxidation of pyrite by oxygen, accompanied by dissolution of carbonates, was the predominant reaction controlling the quality of the water being discharged from the stope. Concentrations of metals released as a result of acid production remained near or below detection limits. Metals release after mine flooding is expected to remain low as a result of the buffering by the sandfill and the reduced rate of oxidation.

Jan 1, 2010

By Edward S. Cook

For several years past, dating particularly from the days of serious "ore-dirt" complications at the Warwick furnace, I have been desirous of providing some safe, quick and easy method of relieving the tuyeres of slag, when the cinder- and iron-notches are chilled through loss of heat in the clucible or when, from dropping or jumping of stock, the molten slag is forcibly driven into the bellyand leg-pipes. Various methods were proposed, but objections of one kind or another always presented themselves, and the subject was postponed to a more convenient season. In the summer of 1887, while running on anthracite alone, 1 found the various expedients in use to be so utterly valueless, that the importance of a practicable tuyere slagging-valve impressed me more forcibly than ever. The holes left in the cast-iron jacket at one side of the bottom of the water-blocks were found to be of no value whatever. The swinging or hinged cap on the elbow of the belly-pipe, while convenient to permit the removal of lag after the belly-pipe was partially or wholly filled, could not be adapted to discharge the slag before solidifying, except at great risk to the men and loss of time just when the constant running of the engine and the keeping of blast on the furnace was of the utmost importance. By removing keys from the caps and holding them in place with props, the slag could be discharged through the tuyeres and belly-pipes, with the engine running, by knocking the props away at a given signal. This method is extremely hazardous to life and limb, and I have always hesitated to make use of it. When the furnace is in such condition as to require the adoption of some method of the kind, the stoppage of the engine, cooling the blast and the contents of the crucible, always aggravates the trouble. When the caps are blown open and the slag is discharged by removal of the props, it is necessary to stop the engine to replace them. An hour or more will elapse before this can be done, as the slag must be partly removed before the tuyeres can be approached by ordinary mortals, and the caps handled and fastened in place again. Any movement of the stock is liable to burn the workman, as he stands, securing the cap in front or at one side of the open belly-pipe.

Jan 1, 1889