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By Pedro Beltrán

DURING the war South America attained a very important position in the production of metals and minerals, brought about by her strategic location near the "Arsenal of Democracy" and the loyalty of her peoples to the cause of freedom This seemingly miraculous achievement in the wartime delivery of the all-essential metals-copper, tin, lead, zinc and tungsten -as well as 35 other war-important minerals and metals, was not the simple result of orders received and of routine production It was the end result of pioneering, prospecting, developing, planning and plodding throughout the lifetime of your organization It was the introduction of new engineering principles, mining techniques, smelting procedures and refining practices, which presaged the entrance of the vast amount of venture capital essential to carry these promising mineral potentials through the dangerous stages of early development Many of those attending the meeting must in the past, as young engineers, have braved the untold hardships and discouragements that beset them at every turn Only they can really appreciate the true meaning of the overwhelming wartime demand on the mineral production of every one of the South American countries No one country has all of everything necessary to produce armaments on a scale imperative during an emergency Not even the United States, with its wealth of natural resources, could hope to meet the unprecedented de-

Jan 1, 1947

By Edward Skewes

In view of the importance of the Cripple Creek district, the large amount of the publications concerning it, and the circumstance that many members of the Institute reside in it, or are familiar with it through repeated visits, it is surprising that our Transactions should have remained so long without any contributions on the subject. The same observations may be made with regard to the Witwatersrand, in South Africa, the other great productive gold-field of recent development. And I suppose the explanation is the same in both cases, namely, that the members of the Institute persoilally acquainted with the

Jan 1, 1897

By Edgar Stansfield

WHEN plants decay in a peat bog the woody parts form a brown pasty mass, or peat muck, largely soluble in. alkalis. This brown matter has been termed "ulmin." The same material, but commonly black in color, is found in coal, and there is evidence of the similarity between the material forming the main bulk of the coal and the bulk of the more recently decayed material in peat bogs. The. more recent or low-rank coals, such as lignite, little removed from the peat stage, contain notable percentages of alkali-soluble ulmins, but the percentage decreases with increased, degree of coalification and is negligible in bituminous or higher rank coals. The determination of the alkali-soluble ulmins in any coal gives, therefore, an indication, of its degree of coalification or rank. Coals which contain few or no ulmins soluble in alkalis do contain ulmins which can be rendered soluble by oxidation. The higher the rank of the coal, the more difficult it is to oxidize the insoluble ulmins and make them soluble. High-rank coals can be differentiated by oxidation tests on the, insoluble ulmins; but low-rank coals can be characterized by both their soluble and insoluble ulmins. This paper deals with the determination and significance of the alkali-soluble ulmins, present, as such in- the coal. The chemical nature and composition of ulmins are not discussed.

Jan 1, 1932

By Russell W. Dayton

THE metallurgical polarization microscope has been utilized in several researches in the last few years, thus attaining a fair degree of prominence, but little has been written in a manner suitable to a metallurgist concerning the theory of this instrument. In this investigation the theory was carefully studied, and the results are presented here in a detailed manner, yet as simply as possible. The theory - is discussed with particular reference to the three chief functions of the instrument: (1) determination of anisotropy; (2) effect of strain; and (3) identification of inclusions. Each of these is investigated experimentally, with especial attention to the mechanism of producing any effect. Where possible, the discussion is supplemented by photomicrographs. The instrument used had numerous defects as a polarization microscope; these and their remedies are discussed. In the microscopic study of transparent mineral sections (chalcography) the use of polarized light has aided tremendously in the identification of a mineral. The determination of strain in transparent substances (photoelasticity) by the use of polarized light has lately become a commercial process, used in testing finished glass articles. The success of the use of polarized light with opaque materials has not been so great. The magnitude of the effects obtained is much less than that of the corresponding effects with transparent materials, and the mechanical difficulties are much greater. Königsberger, (1)‡ in 1909, was the first to apply polarized light to the microscopic study of

Jan 1, 1935

By W. L. Saunders

It is now generally admitted by experts that at least so far as rapid progress is concerned the Alpine system of tunnel-driving is superior to any other. This is perhaps natural in view of the record of experience in driving tunnels through the Alps. These great mountain-chains cannot be treated in the ordinary way by shaft-sinking and driving headings, thus multiplying the points of attack. The work must be done from the ends only, hence speed in driving is of the utmost importance ; and, as necessity is the mother of invention, the concentration of effort to make progress has resulted in an organization and in mechanical appliances that have produced results so much in excess of the usual practice, even in America, that a discussion of the subject in detail should be of much value to the engineer and contractor. The first Alpine tunnel mas the Mont Cenis, length 7.5 miles, driven with a progress that averaged about 7.75 ft. per day. Next came the Saint Gothard, 9.5 niiles long, 18 ft. per day; Arlberg, 6.5 miles long, 27.25 ft. per day; Simplon, 12.25 miles long, 36 ft. per day. The figures represent progress when driving from two headings, so that by dividing them in two we get the daily single-heading progress. The latest of the Alpine tunnels is the Loetschberg, now being driven. In this work the world's record has been beaten by a single day's record in one heading of 36 ft. and by an average daily record in one heading of 29.5 feet. The Alpine range forms a natural barrier between a large section of northern and southern Europe. This range extends from the southeast of Prance to the frontier of Hungary, betveen Italy and the plains of sonthern Germany. The contour

Jan 1, 1912

By E. C. Harder

IN view of the gradually decreasing known reserves of high-grade manganese ore and the rapidly increasing consumption of iron-manganese alloys in the steel industry, it is well to turn our attention to the development of low-grade manganiferous ore deposits and to the utilization of these ores in steel manufacture. The dependence of this country on imported manganese ore and ferromanganese has been forcibly brought to the attention of steel makers during the last few years by the cessation of manganese-ore imports from Russia, the restriction of manganese-ore imports from India and of ferromanganese imports from Europe. Should the importation of manganese ore from Brazil cease, the steel industry of this country would face a serious situation. The present practice of steel making requires ferromanganese in large quantities and ferro-manganese of the grade used at present can be produced only from high-grade manganese ores such as the United States appears to possess only in insignificant amounts. There are in the United States, however, large reserves of manganiferous iron ore which could probably be used extensively in the steel industry if certain changes in the practice of steel manufacture were made. Thus high-grade manganese ore could be conserved. Among the most important deposits of manganiferous iron ore in this country are those of the Cuyuna iron-ore district of Minnesota. It is probable that in case of restriction of foreign supplies, the users of manganese in the United States would have to rely to a large extent on the Cuyuna district to make up the shortage.

Jan 9, 1917

By John Griffen

THEORY HYDRAULIC classification as explained by Rittinger and others was largely restricted to conditions wherein the free-falling velocities of the particles were conceived as governing the separations effected (see chapter 9). The laws governing classification under free-falling conditions have been summarized by Chapman and Mott as follows: 1 Nomenclature r represents, in a particle of irregular shape, the round-hole screen through which the particle would pass, or some other linear dimen¬sion of the particle equivalent to d, the diameter of a sphere. s, the specific gravity of the particle. 1, the specific gravity of the water used as a medium. K, a constant. W, the velocity of the water. In an Upward Current of Water 1. A particle will move upward if [W > KVr(s-1)] and, by suitably regulating the speed of the water current, the larger and heavier particles may be made to fall downward against the current, leaving the smaller, lighter particles in suspension in the current. 2. Particles such that [T1= s2-1] cannot be separated in an upward-current classifier with any one velocity of current. Coal particles having a specific gravity of 1.35 cannot be separated from refuse particles of 2.5 sp. gr. Unless 2.5-1 the ratio of diameters is less than [1.35-1 or 4.3 to 1,] and the raw coal must be screened to size limits within this ratio if they are to be separated. Cone¬-shaped vessels or vessels of other shapes that allow the use of&apos; different velocities of current at different points in the flow are used to modify this limitation. 3. During the initial stages of motion, coal particles ascend more rapidly than refuse particles of the same size. 4. A particle will ultimately fall if [W < KVr(s-1).] If particles of

Jan 1, 1950

As the radical element has secured control of the various local printers&apos; unions of New- York City, 250 magazines have temporarily suspended publication rather than grant their demands. The actions of. these local unions have been repudiated by the officers of the different inter-national unions, who are seeking in every way to carry out their agree-ments with the publishers. The charters of the local pressmen&apos;s and feeders&apos; unions have been revoked by the international officers and new local unions are being formed. Members of the typographical union are not, as yet, directly affected by the strike, but many of them are taking "vacations," which accomplishes the same purpose as the strike but without the odium. The Engineering and Mining Journal, with true engineering spirit refusing to admit insuperable obstacles, is sending out a two-page printed market bulletin, together with two typewritten pages, making an an-nouncement of its predicament and giving brief items of mining news. Thus s brought home to the members of the mining profession in a very direct way the pernicious results of unrestrained control of labor organi-zations-by foreign and un-American elements. No sermon on this sub-ject is required, as the facts themselves are sufficiently eloquent.

Jan 11, 1919

By John J. Croston

THE year 1935 witnessed one of the world&apos;s oldest industries-gold mining-attain the stature of a billion dollar business. Preliminary estimates indicate that somewhat over 30,000,000 oz. of gold was pro-duced, the largest output ever recorded and exceeding the previous year by more than 11 per cent. Of this huge total the Witwatersrand field produced about 10,800,000 oz., compared with 10,480,000 oz. in 1934. Russia was apparently the stellar performer, and from incomplete data it appears that between five and five and a half million ounces were produced by the Soviets compared with 4,200,000 last year and 2,814,000 in 1933. The United States nosed Canada out of third place with a production of 3,546,000 oz. against 2,916,000 in 1934, while Canada increased her total from 2,965,000 to 3,291,000 oz. Similarly, gains of lesser magnitude were made in Australia, the Gold Coast and other countries. As a result of great activity in developing outlying areas on the Rand, and the great number of new companies building mills in Canada, Australia, the Gold Coast and the United States, the years 1936 and 1937 should see new high records, as these new producers will more than offset any decline in the older properties. The whole world has become "gold conscious" during the past three years. It has been the subject of innumerable articles by economists and others, but, unfortunately, because of their lack of actual mining knowl-edge, they have treated the production of gold as a static affair, ignoring geological and technical factors. It is hardly necessary to draw attention to the fact that the world&apos;s gold-mining industry was slowly but steadily shrinking in importance, owing to the gradual depletion of known deposits that were profitable to work at costs existing prior to 1929. The International Geological Congress at Pretoria and the League of Nations Committee drew atten-tion to the estimates of the mining experts of the various governments predicting a steady falling off in world production. On the Rand there

Jan 1, 1936

By Robert Anderson

The diffraction of x-rays by cold-worked and heavily polished surfaces of metals gives, no evidence of an amorphous state and typically perfect crystallographic diffraction&apos; patterns are obtained. Severely cold-worked metals, reduced as much as 98 per cent. in area, give true crystallographic diffraction patterns, and polished surfaces of large single crystals of metal give typical crystallographic patterns. The conclusion is drawn, on basis of x-ray evidence, that metals are fragmented on cold work and polishing and not amorphized. THE purpose of this paper is to report evidence, regarding, metal: structures, that is contradictory to the amorphous-metal, hypothesis of Beilby, and particularly evidence that is opposed to the proposition that a vitreous amorphous layer is produced by polishing a piece of metal. According to the theory of Beilby, which has been developed, by Rosenhain and others, polishing a piece of metal greatly affects the condition of the metal at or near the surface polished, making that surface entirely different in character from the metal beneath. A vitreous amorphous surface film is said to be formed. The polishing process, on the basis of Beilby&apos;s explanation, is well known-and does not&apos; require discussion here, but it is advisable to seek the precise meaning of,., the term "amorphous." According to Beilby, "amorphous means. Non-crystalline in the most intimate sense of the word&apos;; the molecules are not marshalled in crystalline order and orientation." According to Rosenhain, the amorphous condition is that assumed by a metal when, the .crystalline arrangement is completely broken up so that the atoms exist in a state of disorderly arrangement similar to that ;which exists in the liquid state. Thus, from the point of view of the phase rule, the "amorphous phase" is regarded as being identical with the liquid phase. Amorphous metal is often likened to an undercooled liquid. A crystalline substance is one in which the atoms are arranged in space according to some definite repeating geometrical pattern. The existence of amorphous metal has not been definitely proved.

Jan 1, 1925

By Y. Fukunaka, Y. Kondo, Z. Asaki, S. Nakashita

The pyrite smelting process in which about half amount of sulfur is recovered from pyrite by thermal decomposition in an oxygen-free high-temperature combustion gas flow in the flash smelting furnace is being conducted at Kokkola Works in Finland. A mathematical model of this process was developed, and the rates of thermal decomposition and fusion of suspended sulfide particles in the reaction shaft of furnace was calculated. This model is thought to be appropriate because of a fairly good coincidence of the calculated length of reaction zone with the shaft height of the furnace at Kokkola Works. The calculated reaction zone in which the thermal decomposition and fusion of sulfide particles occur becomes longer when pyrite particles of larger sizes are fed. The feeding rate of pyrite particles and the gas velocity at the nozzle exit are also the important operating factors. These two factors are closely related to the volume fraction and the residence time of suspended particles in the gas stream, and the optimal combined levels of these factors at which the length of reaction zone becomes minimal were obtained.

Jan 1, 1976

By W. P. Sykes

RECENT investigations of the molybdenum-carbon alloys have been reported by Becker and Ebert1,? Westgren and Phragmén2, T. Takei3, and H. Tutiya4. Takei3 studied the Mo-C system by employing metal-lographic and X-ray methods, and the other publications described the determination of the crystal structure of the molybdenum carbides. In exploring this system by a technique previously applied to the tungsten-carbon series5, the results of Takei were confirmed with two definite exceptions; i.e., first the composition of the eutectic, and second the nature of the carbon-rich intermediate phase. Consequently, a more thorough examination of the molybdenum-carbon constitution was initiated in an effort to correlate the data supplied by the microstructures, diffraction patterns and chemical analyses.

Jan 1, 1935

By Thomas Leonard Watson

Sulphide ore-bodies of more or less lenticular shape occurring in metamorphic crystalline schists, gneisses, and slates, and conforming closely in strike and usually in dip to the inclosing rock, have been recognized and described along the Atlantic seaboard from Quebec to Alabama. The ore-bodies do not entirely conform, in all cases, to the structure of the inclosing schists, but they sometimes cut across the foliation in dip, though conforming more closely with the direction of strike. In composition the principal sulphide mineral is usually py-rite or pyrrhotite, or both, accompanied by copper, frequently gold, and almost always some sphalerite and galenite. Other metallic ores are, so far as these sulphide bodies have been investigated, less common; silver is not uncommon, and in some of the pyrrhotite masses nickel is present in quantity sufficient to be commercially valuable. Cobalt frequently accompanies the nickel, usually in smaller amount, and the two vary much in relative proportion. Quartz and calcite are probably the most common of the non-metallic minerals. A number of silicate minerals are frequent representatives in one place or another ; garnet, am phi-bole, biotite, pyroxene, zoisite and others. The sulphide bodies of Virginia, comprising both pyrite and pyrrhotite, are among the most extensive along the Atlantic seaboard. Among the pyrite bodies may be mentioned the well-known and extensively worked mines of Louisa and Prince William counties, located on the main pyrite belt (A, Fig. 1) of the middle and northern, eastern Piedmont region in Virginia, and among the pyrrhotite bodics is the famous " Great Gossan Lead" (13, Fig. 1) of the Floyd-Carroll-Grayson coun-

Jan 1, 1908

By Waldemar Lindgren

THE important investigations of Dr. G. F. Becker at Steamboat Springs, Nev., in 1885, aided by the analytical work of W. H. Melville, established the fact that sulphides were being deposited at the surface by hot ascending waters.1 Steamboat Springs is situated near the eastern base of the escarpment of the Sierra Nevada, six miles distant from the Comstock lode. In a region of former volcanic activity, hot springs with a temperature of about 80° C. break forth through a fissure in granodiorite, and at the base of a basaltic bluff the waters have deposited a large amount of siliceous and calcareous sinter, some of which is colored red by antimony sulphide. The sinter from one of the springs was analyzed by Mr. Melville,2 and his results, re-calculated to grams per kilogram, showed [ ] The relative quantities of antimonious and arsenious sulphides are not given in the above analysis, but I believe that the former greatly predominated. The water of one of the springs was also analyzed by Melville and the re-calculation of this analysis to salts that were possibly present is given in Table I.

Jan 1, 1913

By James Herbert Bartlett

The MANUFACTURE of Iron in the PROVINCE of Quebec. The St. Maurice Forges.—The deposits of iron-ore in the St. Maurice district, in the rear of Three Rivers, were probably known to the Indians and .Jesuits, but it is not till 1667 that any discovery is reported. The affairs of the colony were then in the control of the " West India Company," who amongst other monopolies had a right to all mines and minerals." Specimens of the iron-ore were examined in Quebec. in 1668 by the Sieur la Potardière, who reported unfavorably on them. In 1671, Louis de Buade, Comte de Frontenac, was appointed governor of La Nouvelle France ; and in the original manuscripts relating to his administration some allusion is occasionally found to the St. Maurice iron mines.? In a letter to the Imperial Government, dated 2d November, 1672, he says: "The iron mine of which I have already spoken is of great consequence. I have visited it myself, in order that I may be enabled to give a more accurate account of its nature. I am gratified to learn that another mine has been discovered in Champlain, which is much richer than the Cap de la Madelaine mine, and the ore is in greater

Jan 1, 1886

By Philip Wilson

THE Province of British Columbia covers 382,000 sq. mi., about 250,000 sq. mi. of which have not been prospected. In fact, the coast country and the islands are so heavily timbered and the surface covered with so thick a mantle of soil, muskeg, and, over broad areas, glacial drift, that prospecting, and even trail breaking are extremely difficult. It is only along the coast or stream channels, or above the timber line, or where snow or rock slides have scoured the surface that rock outcrops can be found. Glaciers nestle in many of the cirques and fill the valleys in the higher ranges. Great ice sheets and perpetual snow persist in certain localities, thus reducing the exposed areas worth prospecting. Almost the entire country has been subjected to intense glaciation, so that the conspicuous oxidized outcrops of orebodies typical of the south-western United States and Mexico do not exist and surface bodies of enriched or oxidized ore are rare. With few exceptions, the mines1 of the Province are working primary ore. Developments have proved that some of these orebodies are large and important, although usually comparatively low in grade. Besides the few mines that have produced most of the minerals, there are many small mines, but their total output is unimportant. Considering the number of mines and prospects and the widespread mineralization, it is strange that no really great mines, comparable in size and richness with those in the western United States have been found.

Jan 8, 1922

By G. Lavagnino

The old Telegraph mine lies on both sides of Bear gulch, a short branch of Upper Bingham canon, and nearly in the center of the group of mines called the Bingham Mines, about twenty-seven miles southwest of Salt Lake City. It is considered, by local miners as the most important mine of the district. The geological formation consists of Weber quartzites, with subordinate conformable limestones and shales, alternating with porphyritic rocks. These widen towards and connect with the massive backbone of the Oquirrh mountains, while the quartzite develops itself on the slope broken through by Bingham canon. The porphyry not only runs between the strata, but also cuts across them, isolating large portions near the mountain mass, and again on a smaller scale it penetrates some joints in the quartzite. It is a crystalline felspathic rock, containing variable proportions of quartz, mica, hornblende, chlorite, and iron pyrites as accessories. In places, it takes a less distinct or almost uniform fine-grained structure. It has a gray or greenish, and, when much altered, also a reddish or even white color. The quartzite is a fine-grained or almost compact grayish-white or bluish or reddish quartz-rock, containing in places fine scales of mica and grains of iron pyrites as accessories. The raised, folded, or broken masses show well-defined bedding-joints, and their general dip is 35 to 50 degrees towards north or northwest. In the porphyry occur metalliferous veins with a prevailing N.E.S.W. strike. These are in general narrow veins; their principal contents are not dissimilar from those of the other deposits; but there is considerably less oxidation near the surface and the ore is mostly richer in silver and gold. In the quartzite the ore-deposits generally occur on the joints of bedding. The more important deposits occur either in clearlydefined contact-veins or, more often, in somewhat vaguely-defined mineralized zones, that could be called contact-zones. These comprise several masses of more or less altered or decomposed rocks and the newly-distributed products of their mechanical and chemical decomposition, such as breccia and clay in seams or in more irregular bodies..

Jan 1, 1888

By J. F. Blandy

IN October last, I was call upon to examine a copper deposit in the South Mountain, near the Pennsylvania and Maryland boundary. The specimens shown me contained oxides and carbonates with native copper, and were similar to some that had been described to me some years ago as existing at the Luray Gap in Virginia. An examination of Rogers&apos;s Report on the Geology of Pennsylvania, led me to expect to see his so-called "Primal Formation," such as exists throughout the southeastern district of the State. I was therefore much surprised on arriving at the summit of the Western Maryland Railroad to find myself on familiar ground. Instead of the "Primal" as I had known it in Southeastern Pennsylvania, I soon decided that the rocks were identical with the "Lake Superior Copper Formation." My visit was unfortunately a short one, part of two days, and in that time I had to pass over a good many miles, but I saw sufficient to convince me that instead of the Lake Superior Copper Formation being a local geological feature, it would have to be considered as a widely extended series of rocks. I was unable to even approximately estimate the thickness either of the trap zone or other members, schists and slates, of the series. In an article on the Copper Range of Michigan, prepared by C. P. Williams and myself in 1862, and published, in vol. xxxiv of the American Journal of Arts and Sciences, we endeavored to divide that range into zones, according to the character of the traps. The limited nature of the explorations at that time made this work very imperfect. Subsequent explorations have confirmed my notes then

Jan 1, 1879

By Tomoyuki Moritani, Atsuyuki Mizuno

A concentration of manganese nodule varies areally from 0 to 30 kg/m2 in the central-eastern deep sea bottom of Central Pacific Basin with depth of 5,600-5,900m, but generally it is low, mostly of the abundance order from 0 to less than some kilograms per square metres through the bottom. A high concentration over about l0kg/m is localized to the northwestern basin, besides "St. 414 Deep Sea Hill" and “GH 76-1 Trought”, and also it is likely related with the substratum of deep sea clay. Nodules are tentatively classified into nine types of Sr, SPr, SEr, Db, Ss/SPs, ISs, IDPs and V, in terms of morphology and surface feature. The types may be related with internal structure, nuculeus, mineral composition, chemical composition, occurrence and areal distribution, and might have resulted from various environmental factors of nodule genesis. The abundance of nodule at each station shows the interesting relation with acoustic records by 3.5KHz and seismic reflection profilings. In both the records, thick transparent layer over about 45m thick yield neither any nor significant amount of nodule. The layer less than 45m relates with abundant nodules up to 30kg/m2, though it yield also very little nodule in some cases. The relation suggests that the formation of nodule most likely could be related with the accumulation rate of the post-middle Eocene sedimentary sequence to some extent and also with other controlling factors. The relation can lead us to the tentative delineation of distribution of nodule deposits in the area. The comparative-consideration with the deposits in GH 74-5 area, just east- ward of the present area, shows the areal peculiarity of nodule genesis in deep sea bottom. The results of chemical analyses will be discussed elsewhere.

Jan 1, 1976

By Maurus Seet

Mainland China, with one-fourth of the world&apos;s population and one-tenth of its coal production, can no longer be ignored as a considerable force on the world energy scene. In terms of annual productivity, China&apos;s 300 million tons of coal rank third behind the Soviet Union with 655 million and the United States 557 million (1968 Minerals Yearbook. USBM). When viewed from another angle, 1967 figures show that increased productivity from all coal-producing continents, with the exception of North America, was led by Chinese-dominated Asia with a 19% gain. Not unpredictably though, China, on a per capita basis, is closer to the bottom of the list among members of the industrial community. Despite its misspent youth, and despite the set- backs caused by the Big Leap Forward of the late 50&apos;s and the Cultural Revolution of the late 60&apos;S, the People&apos;s Republic has managed to make some impressive strides in developing its coal industry over the past twenty years.

Jan 1, 1971