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By R. Henry Norton

The State of Oregon, although admitted into the Union February 14, 1859, is to-day, so far as any practical knowledge of its mineral resources is concerned, almost terra incognita, as compared with the other Western States and Territories. This is partly to be accounted for by the class of emigrants who first settled in the country ; they seem to have been, as they still are, a pastoral community, to whom the terms " mines " 'and " mining " are synonymous with bankruptcy and disaster, and who discourage all attempts to develop the mineral resources of the State. This statement is emphasized by the fact that Oregon has no State Geolo-

Jan 1, 1891

By Alfred F. Brainerd

A few months since, Prof. Lawrence C. Johnson, of the U. 8. Survey, discovered in Mississippi large deposits of carbonate iron-ore, geologically located in the Claiborne formation of the Tertiary Epoch. These deposits are not pockets, but continuous layers or beds extending for miles, and can be located with certainty where they have not been removed by erosion. Upon examination, recently made by G. W. West, Birmingham, Ala., the largest deposits and highest grades of ore were found near Enterprise, Lauderdale county, and in Clark county, Miss. These beds measure from 10 to 18 feet in thickness, are superimposed upon a " burr rock," associated with green sand, and dip 30 feet to the mile southeast, at an altitude of 350 feet above sea-level, can be

Jan 1, 1888

By G. E. Karantzavelos

A novel two-stage froth flotation process for the recovery of pure magnesite from low grade ores is described. The process consists of a first-stage, magnesite flotation step where a rougher magnesite concentrate is floated with amine collectors. The first-stage froth concentrate is then repulped in fresh water, and quartenary ammonium salt and fuel oil are added to float the remaining impurities. The results from laboratory batch tests show that a high-grade magnesite concentrate assaying 0.99-0.20% Si02 and 2.84-0.46%a Ca0 can be produced. Regulation of the variables controlling magnesite froth flotation also allows the variation of the ratio % Ca0: % SiO2, between the acceptable limits 0.32 to 5.79. This ratio is important to the quality of dead-burned magnesite.

Jan 1, 1985

By John W. Cabot

In the manufacture by the Bessemer process of soft steel suitable for rolling into fine sheets, tubes and 60 forth, a difficulty is sometimes met with, in the tendency of this kind of metal to rise violently and boil in the moulds while being cast; this results in hollow-topped ingots, and consequently in an undue amount of scrap in the subsequent rolling. It has been noticed that this peculiarity does not pertain to all pig-irons, some grades producing a blown metal which pours quietly, while others, in whatever way the blow may have been conducted, give a metal which rises in the moulds, accompanied by the evolution of large quantities of hydrogen and carbonic oxide gases, and requiring a long time to solidify. This difference in behavior has been some-

Jan 1, 1891

By Byron W. Cheever

In working up the process which I described at the Chicago Meeting, May, 1884 (p. 163 of the present volume), for the estimation of phosphorus in iron and steel, I employed samples of steel obtained from one works only, and of a given brand. Since then I have had frequent occasion to test the process on other steels, and find that it works equally well. But some steels present certain colors which may mislead the operator; and I therefore propose a slight change in the directions formerly given. On the second page of my paper, in the second paragraph, I would substitute the following modified directions: Place the flask under the hydrant, till the solution is perfectly cold ; then add, gradually, strong ammonia, with constant stirring, till the solution is changed into a pasty mass and the ammonia is in slight excess; then add cautiously HNO3 (1.40 specific gravity)

Jan 1, 1885

By H. T. Wyatt, A. S. Baptie

The Ten Section field is approximately 10 miles southwest of Bakers-field, Kern County, Calif. (Fig. 1). There is no surface evidence of the existence of the Ten Section structure, which subsurface exploration has shown to be a gently folded, anticlinal dome. Regionally, this field occurs as a fold in the deeper beds of the gently rolling floor of the San Joaquin Valley. It is on the easterly slope of the valley, its position with relation to the axis of this syncline not having been determined. The field was discovered by Shell Oil Co. with the completion of well Stevens A-l, on June 2, 1936, at a depth of 7888 ft. The location for this

Jan 1, 1938

By Cornelius J. Dwyer

It is possible to hold a very optimistic view of the future of the U.S. coal industry, and there are those in the coal industry who generally choose to do so. For example, a major coal company stated recently in its annual report, "Coal's prospects appear brighter today than at any period in the past." In order to continue in this state of euphoria, it is only necessary to remind oneself of the following "facts":

Jan 7, 1967

By Charles E. Heinrichs

There arc still ample reserves of phosphate in Florida and Tennessee, but the richest low-cost areas have been exhausted. The miners, by the introduction of more efficient equipment, have succeeded in preventing material increases in production costs. Further mechanical improvements could not be expected to keep up with the factors tending to increase costs. While the conventional phosphate "washers" are capable of recovering practically all of the plus 1.5-mm. phosphate from the matrix, approximately 50 per cent of the phosphate values are in the minus 1.5-mm. sizes. Flotation now affords an economical and efficient means for recovering the fine ( — 1.5 mm.) phosphate formerly discarded to waste dumps. Through the reclamation of dumps and recovery from current washer wastes, flotation has doubled the reserves of Florida and Tennessee. By doubling recoveries from the matrix, flotation reduces capital investment requirement and substantially reduces production costs. It definitely improves the grade of the total production and provides a flexibility of operation that cannot be obtained by any other known means.

Jan 1, 1934

By Allan Gibb

The ores of copper are usually associated with minerals containing arsenic, antimony and bismuth. Whatever the means adopted for extracting the copper, these metals are usually found, to a greater or less extent, in the product. There is, however, usually some elimination in the various metallurgical operations to which the ores are subjected, and some attempt is made here to determine the degree to which this elimination is effected.

Jan 1, 1903

By A. F. Beasley

FROM the initial Bunker Hill smelter operations in 1917, to March, 1930, only 50 per cent of the ore production of the Bunker Hill and Sullivan Mining and Concentrating Co. was handled at this plant. Since the date last mentioned, the total mine production has been received. The old lead refinery was equipped with four 105-ton drossing kettles, three 110-ton softening furnaces, four 105-ton desilverizing kettles, three 100-ton refining furnaces, one 150-ton round refined lead-storage furnace, one 75-ton residue furnace and one hand-operated casting wheel. This equipment, with the exception of the residue furnace, could not adequately handle the increased tonnage in addition to the regular supply of custom ore. It became necessary either to install additional furnaces and kettles or to rebuild the entire plant, installing equipment of greater capacity.. The latter course was chosen, partly because of lack of space for additional equipment but mainly because of the more economical operation of larger units.

Jan 1, 1932

For the first time in the history of shaft sinking, the concept of mid-shaft loading has been used. By making use of available hoisting capacity during drilling periods, development work on underground hoist chambers and ore-pass and ventilation by-pass systems at Vaal Reefs South gold mine is being done simultaneously with sinking. This factor, together with the unusual configuration and design of the twin-shaft system at Vaal Reefs South, and the use of raise borers in the installation of ore-pass and ventilation by-pass systems, will mean that the shaft will be commissioned at least a year earlier than would have been possible had conventional methods been used. The possibilities of mid-shaft loading in reducing the time normally taken by shaft service development were recognized by Anglo American Corp. consulting engineers and Shaft Sinkers Pty. Ltd., the company which is sinking both shafts at Vaal Reefs.

Jan 1, 1970

By H. R. Hardy

The study of the mechanical properties of geologic materials was initiated in the Mining Research Section of the Fuels and Mining Practice Division in 1951 as part of a fundamental study of ground stress in Canadian coal mines.1 Early in the investigation of the mechanical properties of geologic materials, however, it was realized that the test results are influenced by the rate and the duration of loading. For this reason, laboratory investigations2,3 were undertaken to study the effect of long-period uniaxial stress on the deformation and failure properties of these materials. A literature survey indicated that work on the time-dependent properties of geologic materials had been very limited in the past.

Jan 1, 1965

By John Birkinbine

Awakened public interest in efforts to conserve natural resources will certainly be appreciated by the members of the American Institute of Mining Engineers, and a discussion upon conservation may well form a part of one of the Institute meetings, for the records of papers and discussions which appear in the 38 volumes of its Transactions are replete with evidence of efforts in this direction. Every process which reduces the fuel consumed or the power applied per unit of product; every utilization of waste material, or employment of that formerly rejected, to obtain something of value; every feature of construction or operation which lessens the labor required or increases the output per employee, is an advance in the direction of true conservation. This may not appear from the records of late conferences or from published articles, in which the effort seems to be concen-

Jan 1, 1910

By Thomas M. Brown

The method usually employed in accurate determinations of sulphur in pig-iron and steel is to treat a weighed sample of borings in a flask with muriatic acid, and to pass the gaseous products through an alkaline solution of lead or silver, which precipitates all the solphur of the sulphuretted hydrogen in the form of sulphide of lead or silver. The sulphide thus formed is subsequently oxidized by aqua regia, bromine, or other oxidizing agent, and the sulphuric acid formed precipitated in the usual way by chloride of barium. I have substituted for the alkaline metallic solution, a solution of permanganate of potash in the strength of one gramme of permanganate to 200 cubic centimetres of water, and find that it gives results quite as accurate as those obtained by using an ammoniacal solution of silver. By the employment of the permanganate it will be readily seen that there is considerable saving of time and work. In order to test the accuracy of the method, six samples of pig-iron borings were weighed out (about six grammes each) and treated identically

By M. D. Hassialis, C. G. Myer

THE nature of a collector-coated mineral surface has been the subject of some experimentation and much speculation. Various aspects of the problem have been isolated and studied; it is probable, however, that there exist aspects as yet unrecognized, which are needed for a complete description of the system. The recognized elements of the problem are: 1—The nature of the chemical units comprising the film and the nature of the forces holding these chemical units to the mineral surface; 2—The orientation of the chemical units at the surface; and 3—The disposition of the collector units at the mineral surface. This report touches upon all three aspects of the broad problem; it deals, however, with a new and heretofore unrecognized element—the mobility of the collector units in the two dimensions of the solid-liquid interface. Regardless of the viewpoint adopted as to whether the chemical units comprising the collector film are collector ions or molecules, held either by chemical or physical forces, the writers on flotation theory are in apparent agreement as to the orientation of the chemical units at the mineral surface. Wark and Cox' showed that the contact angle at a stable collector-coated surface in a constant chemical environment is independent of the nature of the mineral and of any resurfacing agent; it depends solely upon the collector used. They showed further that the value of the contact angle increases with the number of carbon atoms in a homologous series of compounds. Taggart, Taylor, and Knoll2 postulated that the collector ion is oriented with the chemically reactive, polar end toward the mineral surface and the non-polar, hydrocarbon-like end toward the liquid phase. In support thereof they cited the abstraction of p-p1 dihydroxydiphenylthiourea and of glycol xanthate8 by galena without a concomitant increase in the contact angle above that of clean galena. It was argued that in these cases the water-repellent layer which normally would be presented to the liquid phase owing to the orientation of the collector ions is overlain by a layer of water-avid groups, the hydroxyl groups. Implicit is the analogous orientation exhibited by a monomolecular layer of an insoluble substance at an air-water interface. It should be pointed out that these facts also are consistent with the concept that the collector units be flat on the surface of the mineral and that the response of the surface to an air bubble is determined by the ratio of the area covered by water-avid groups to the area covered by water-repellent groups; the areas being weighted according to the relative watef-avidity or water-repellency of the groups involved. The disposition of the chemical units of the collector film at the mineral surface has not received the attention it merits. Taggart4 concluded from the observed stoichiometry of the ions entering and leaving a surface that the stoichiometry is obeyed in detail at the surface of the mineral. Thus, in the case of xanthate-coated galena, pairs of xanthate ions are attached to surface lead ions. In the case of chemisorption, Gaudin and Preller postulated an agreement between the atoms or ions of the substratum (the mineral surface) with those of the superstratum (collector film); in the case of the physical adsorption their position is not clear. In one place they state "the first type (physical adsorption) does not require any agreement between the atoms or ions of the substratum with that of the superstratum" and in another place that "It seems, in fact, as though some slight influence of the substratum is formed even in physical adsorption." The present work shows that in some cases of chemisorption the chemical units of the collector film are in constant surface-bound motion and may not be assigned to any site of the surface, hence there is no permanent association between the chemical units of the film and the atoms or ions of the solid. The physical property of the collector film that is of paramount importance is its surface energy. Although this property is not susceptible to direct experimental determination, the related contact angle is. Much of the knowledge of the properties of a collector film derives (by deductive and inductive reasoning) from the behavior of an air bubble thereat

Jan 1, 1952

By Peter McKellar

The district around Bag bay in Shoal lake, meat of Lake of the Woods, in the Ontario western gold-fields, is attracting considerable attention at the present time as a gold-producer. A large number of gold-bearing veins have been prospected and mined to a considerable extent in the locality. On the whole they make a fair showing, considering the work done ; and some are undoubtedly rich—the Mikado, for instance. The principal mining companies that have been operating here are the Yum-Yum, Ontario Limited, Cornucopia, Engledue Concession, Tycoon, Toronto and Western and Mikado Cos. I will confine my remarks chiefly to the three companies last

Jan 1, 1900

By Andre Hubaux

In the writer's opinion, more stress should be put on field and microscope observations, as J. L. Gillson does. His discovery of relics of big labradorite feldspars from the Marcy anorthosite in all the other rocks is proof enough that previous field observations have been inadequate. The writer's field experience with anorthositic massifs is limited to the Egersund-Sogndal district in southern Norway; however, this is a very large and well exposed area. It seems to have so many points in common with the Adirondack region that a detailed comparison should be beneficial. This comparison was not possible 20 years ago, owing to the scarcity of geological data, at least for Norway. Both regions are now far better known-the Norway district because of the work of Professors Bugge and Barth33-35 and especially because of the extensive field and microscopic research of P. Michot,36-46 who introduced me in the field to the problems of that region.

Jan 3, 1958

By Carleton Ellis

The problem of the influence of hot surfaces upon gaseous combustion is one which, from a purely scientific standpoint, has engaged, for many years past, the attention of Prof. William A. Bone, of Leeds University and the Imperial College, London ; and as his recent work has been the direct outcome of earlier scientific investigation, it will be appropriate, by may of introduction, to review briefly the present position of science with respect to this important subject, as stated by Professor Bone. One may perhaps best arrive at an understanding of the term " flameless " or " surface " combustion by considering certain facts which differentiate it from the more familiar processes of

Jan 1, 1913

By John S. Alexander

DURING the past few years the block coal of Indiana has been talked about and written upon to such an extent, that almost every one at all interested in such subjects, has been made acquainted with the area and geographical position of the field, the quality and peculiar properties of the coal, the thickness of the veins, the manner of mining, etc. The writer, therefore, taking for granted that, to those present all this is familiar ground, desires more especially to call attention to the position this coal takes in the market, and at those points of consumption where it is brought in direct competition with rival fuels. Chicago, thus far, has been the chief consumer of Indiana block coal, the distance from the mines at Brazil, via Terre Haute and the

By George F. Kunz, Henry S. Washington

The recently discovered occurrence of diamonds near Mur-freesboro, Pike county, Ark., was brought to our attention by Mr. Samuel W. Reyburn (Trustee for Messrs. C. S. Stifft, A. D. Cohn, August Zinsser, Jr., and himself, owners of the property), through whose courtesy we investigated the locality of the deposit. Prospecting with the diamond-drill is now in active progress; but mining operations on a large scale have not yet been ordered. Geology.—The geology as well as the petrography of this interesting locality has been well described by Messrs. J. C. Branner and R. N. Brackett,' but they did not class it as dia-mondiferous, although Branner suggested that it might be. Briefly summarized, the igneous rock in which the diamonds are found is a vitreous peridotite, forming a stock or volcanic neck, which has broken up through the Carboniferous and Cretaceous quartzites and sandstones. After an extensive period of erosion, during which an unknown portion of the neck and pre-

Jan 1, 1909