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By W. R. Opie, O. W. Mole

By confining the electrolytic reduction of TiCl4 to the interior of a porous basket-cathode the electrolyte between the anode and the cathode can be kept free of reduced chlorides of titanium eliminating undesirable reactions of reduced titanium chlorides with brickwork or oxygen in the cell atmosphere. Semiwalls are not needed. Operating conditions are given and discussed. Titanium yields based on TiCl4 introduced are 93 pct. Cell voltage and amperage characteristics are adaptable to multiple cathode-series cell urmngements. EXPERIMENTS conducted in the National Lead Co., Titanium Division, Research Laboratories showed that titanium metal could be deposited in an electrolytic cell in which titanium tetrachloride was introduced through a tubular cathode.' The reduced chlorides as formed were confined to the vicinity of the cathode. They were reduced to form a cocoon-shaped growth of sponge titanium metal at the end of the cathodic tube below the surface of a sodium chloride-strontium chloride electrolyte. No diaphragm was needed.' Although high-purity, coarse crystalline metal was produced in the cocoon growth, the yields of metal removed from the cell, based on the amount of titanium introduced as TiCl4, were usually only 40 to 60 pct. The growth of the cocoon deposits was away from the cathodic tube for introduction of TiC14 toward the anode following the flu lines. The reduced chlorides of titanium diffused through the deposit and were reduced to titanium electrolytically within the deposit or on the outer surfaces. Deposition within the pores of the cocoon was detrimental to further deposition because it plugged the passages used by the reduced chlorides to diffuse away from the point of titanium introduction. As plugging due to deposition in the pores proceeded, the reduced chlorides in the center of the cocoon would force their way out by forming a channel and would escape from the vicinity of the cathode without being reduced to metal. Some work had been done previously1, 2 which indicated that if the end of the cathodic tube for introducing TiC14 was surrounded by a screen connected to the tube so that it too was cathodic, growth could be made to occur within the screen. Direction of growth was observed to be from the screen toward the point of TiCl4 introduction. Through a series of design modifications a cathode evolved which consisted of an introduction tube surrounded by a perforated metal basket as shown in Fig. 1. Modifications of this design are described in Refs. 3, 4, and 5. This basic cathode designa" was incorporated in electrolytic cells containing graphite anodes and constructed of high-silica brick refractory for containing the electrolyte (see Fig. 2). The inner crucible was surrounded by insulating brick and the entire unit contained in a welded steel shell. Suitable cooling chambers with inert gas atmospheres were devised so that the cathode could be removed from the cell without exposing the deposit to air while hot. Various alkali and alkaline earth chlorides were used as electrolytes.

Jan 1, 1961

By M. D. Cooper

IN spite of the uncertainty in the bituminous coal industry during 1933, progress worth recording has been made. Along with other industries, coal has felt the effects of business stagnation, but even in the worst weeks of the past four years, .the total production of bituminous coal in the United States was seldom less than half the production in some of the best weeks of the more prosperous years, a record better than that of many industries. However, the competition of other fuels and sources of power, together with the increased efficiency in the use of coal, has brought anxiety to producers. This has resulted in pressure for reduction of costs, not always by the wisest means. On the other hand, the effort to survive has directed increasing interest toward research, a wholesome development in a difficult situation. Wages, limitation of hours of labor, and the NRA have occupied much time and thought. Following a period .of wage cutting paralleling price cutting, the industry found itself rather suddenly faced by the President's Agreement, followed in due course by the Code, and then in many places by the agreement with the United Mine Workers. Although there is still some uncertainty in regard to the detailed working out of the new arrangements, there seems to be an honest endeavor by the signatories to the Code and Agreement to work them out in a straightforward manner.

Jan 1, 1934

By E. Hornbogen, R. C. Glenn

Copper precipitates from a iron as fcc E phase without formation of intermediate compounds. In the first stage of the precipitation, spherical particles with diameters < 100A are formed at a high rate. During the second stage, the particles grow at a rate given by Zener&apos;s equation for growth of a spherical precipitate. In the third stage, growth is slower. Rod-shaped particles form after long aging times at 700°C. Maximum strengthenzng was observed at the beginning of the second step of precipitation. During plastic deformation of the aggregate, particles appear to deform initially by twinning. THE work discussed herein was part of a study of precipitation of substitutional elements from a iron. Copper was chosen as one of these substitutional elements because it has about the same atomic size as a iron, and does not form an intermetallic compound with iron. The data on the iron-copper system then available were summarized by Daniloff1 several years ago. The solubility of copper in a iron has been determined by electrical conductivity measurements,2 lattice parameter measurements,3 and by saturating thin iron foils with copper and determining the copper content.4 The results of the three investigations do not agree very well, but the value of 2.4 wt pct for the maximum solubility at 840°C seems to be the most reliable,4 Fig. 1. An alloy containing 1.23 wt pct Cu was used in our work to assure starting with a completely homogeneous material. On the copper-rich side of the diagram, there is a maximum solubility of about 4 wt pct Fe in copper at 1094°C ( phase). The precipitation of

Jan 1, 1961

Transit A light weight, totally enclosed theodolite, especially designed for mining, has been placed on the market by Askania Werke, A. G. The instrument weighs only 41/4 lb and measures 51/8 x 71/2 in. without tripod and in a waterproof aluminum hood. It may be mounted on tripod or bracket without removing the protective hood. [ ] Standard equipment includes diagonal eyepiece rotating in all directions which eliminates need to be in line with scope for sighting and makes an auxiliary scope unnecessary for steep sights. The transit reads direct to 1 minute and may be estimated to 6 seconds by means of optical micrometer on both horizontal and vertical circles. The telescope in vertical position serves as optical plummet, sighting through an opening in the base. The instrument is shown above mounted for attaching to a pin driven in timber or rock, eliminating tripod or set-up bar in cramped quarters. The chain clamp in the lower picture is used on timber or steel ground supports. Complete with carrying case and set-up brackets, ready for use in a raise, it weighs less than 6 lb, and the protective hood remains on until the instrument is securely mounted. [ ] Accessories for increasing versatility of this mining theodolite are: tripod, electric illumination for optical micrometer and reticule, close range objective lens, and objective lens prism for sighting vertically in front of the instrument. Circle No. 1

Jan 1, 1952

By S. E. Bretherton

Mr. AllaW Gibb, of Mount Perry, Queensland, Australia, in an interesting and instructive paper,* describes fully the great difficulties metallurgists encounter in seeking to produce marketable copper by smelting refractory ores containing arsenic, antimony and bismuth. After reading this description, I prepared a paper for the Institute, which was, however, through a misunderstanding on my part, published in the San Francisco Mining and S&apos;cie~ztiJic Press of April 4, 1903, after its acceptance by the Council, and without credit to the Institute. Consequently, it cannot be reprinted for the Transactions of the Institute; and I can only here summarize its contents and conclusions, referring the reader to the article above named for further particulars. In that article I omitted the col~sideration of bismuth, which we do not encounter in our smelting at Val Verde, and added lead and zinc, which Mr. Gibb had not discussed; and I undertook to shorn, by the record of a year&apos;s practice of the Val Verde Copper Co., Arizona, that copper-ores containing arsenic, antimony, lead and zinc may be successfully smelted, without preliminary roasting, in an ordinary blast-furnace with hotblast, making a normal slag, such as one would aim to make under ordinary conditions with cold-blast, so as to produce a marketable matte, containing not less than 45 per cent. of copper, free from arsenic and antimony, and below the limit in lead and zinc penalized by the refineries.

Jan 1, 1904

By R. F. Campell, W. L. Jensen

IT is not uncommon for martensitic high carbon steels having a coarse austenite grain size to exhibit microcracks when polished and etched and examined with a microscope, as described by Davenport, Roff, and Bain.&apos; Whether such cracks exist before etching or are the result of acid attack during etching has been debated from time to time. Fig. 1 illustrates the effect of electrolytic polishing, mechanical polishing and etching subsequent to each polish on microcracks produced by oil quenching from 1800°F a steel containing 1.14 pct C, 0.23 pct Mn, 0.33 pct Si, and 0.45 pct Mo. The austenite grain size was 3-4 on the ASTM scale. Grinding on lead laps followed by either electrolytic polishing with acetic anhydride-perchloric acid solution&apos; or mechanical polishing with Linde "B" alumina on "microcloth" (sometimes referred to as Gamal cloth) revealed microcracks without conventional etching, as shown in Fig. la and b, respectively. These same fields, after subsequent etching with saturated picral, are shown in Fig. lc and d, and the cracks are seen to be typical microcracks; moreover, the cracks appear to be broader and longer than before etching. Although the microcracks were revealed by electrolytic polishing alone, the possibility of acid attack was present; however, the mechanical polish was accomplished without any intermediate etching to remove disturbed metal, hence this is regarded as definite evidence that microcracks are present before etching.

Jan 1, 1954

By Garth M. Crosby

Hugh E. McKinstry (Professor of Geology, Laboratory of Mining Geology, Harvard University, Cambridge, Mass.) Pre-Cambrian age for the Coeur d&apos;Alene mineralization, as indicated by isotope studies and recently discussed by Silverman, Long, and Kulp&apos; would explain some features of the mineralogy of the district that have long been a puzzle. In the Silver Belt, especially in the Sunshine mine, lead-zinc min erali zation passes downward into tetrahedrite ore. Although commercially speaking this is a rich silver zone, the silver is, quantitatively, a mere impurity amounting to a small fraction of 1 pct. In effect the zonal change is from lead-zinc down into copper mineralization—-the usual zonal change that occurs in many districts. In the Burke-Mullan portion of the district, on the other hand, lead-zinc ore does not pass downward into copper mineralization of the Sunshine type. Instead, pyrrhotite appears in depth while the tenor in lead and zinc declines. The change occurs at increasingly greater depth away from the Gem stocks, deepening irregularly by some 3000 ft within two to four miles. As noted by Crosby, biotite, grunerite, and garnet appear in the deep zone. The marked difference between this apparent zonal change and the more nomal change to a copper zone is quite explainable if already existing pre-Cambrian veins have been locally metamorphosed by a Tertiary intrusive. The chief obstacle to this explanation is the evidence that mineralization cuts Laramide intrusives, but evidence on this point is conflicting as indicated by Crosby&apos;s observations and summary. This is not the first instance of a problem in determining the time-relationship of mineralization to a spatially associated intrusive. At the Noranda mine veins of chalcopyrite extend into a diabase dike which apparently cuts the ore, although Price2 concludes that the ore is later. However, at the Normetal mine diabase of a similar dike is thought3 to intrude the orebody but is cut by stringers of chalcopyrite. In the Sullivan Mine, B. C.,4 galena follows a fracture in a larnprophyre dike which, itself, cuts the main orebody. In the Sudbury district dikes of olivine diabase are clearly younger than the nickel ore, yet where they cut the Creighton orebody they contain stringers of chalcopyrite. In the laboratory, Hawley5 has developed veinlets of sulfide (chalcopyrite) it] silicate gangue by heating specimens of ore in a stream of H2S at 410 °C. From this and other evidernce. it seems clear that sulfides can be transferred from one site to another — at least through short distances — at temperatures well below their melting points. It would seem then that even if sulfide Mineralization in the Gem stocks can be shown unequ ivocably to be later than the intrusive the possibility of "remobiliza tion" need not be more than local. Thus the zonal relationships are quite in accord with a pre-Cambrian age for original deposition of the lead, zinc, copper, silver, and uranium in the Coeur d&apos;Alene district. REFERENCES 1. A. Silverman, A. Long, and J. L. Kulp: Discussion of: The Gem Stocks and Adjacent Orebodies, Coeur d&apos;Alene District, Idaho. Mining Engineering, May 1960, pp. 470-471; AME Trans., 1960, vol. 217, p. 117. 2. Peter Price: Geol. & O. D. at the Home Mine, Noranda, Quebec. Can. Inst. M & M Bull 263, 1934, p. 108; also,Trans. CIMM 1939, pp. 108-140. 3. w. L. Brown Nometal Mine in structural Geology of Canadian Ore Deposits, Montreal, 1948, p. 690. 4. C. O. Swanson and H. C. Gunning: Geology of the Sullivan Mine. Can. Inst. Mining & Met. Trans. vol. 48, 1945, p. 653. 5. J. E. Hawley: Heat Effects on Sulphides and Possible Applications. Univ. Toronto Studies, Geol. Ser. No. 46, 1941, p. 34.

Jan 1, 1961

By JOHN A. MALONEY

AS noted in the February issue of MINING AND METALLURGY, an advisory committee to the Museum of Science and Industry of Chicago was authorized by the Institute&apos;s Board of Directors, with W. R. Wright of Chicago, former Director of the Institute, as chairman. Since that time the committee has been undergoing organization, and held its initial meeting at the Museum offices in Chicago on April 11 and 12. Functioning as consultants to the Geology and Mineral Industries branch of this new institution, the advisory committee is aiding in building an exhibit which will tell the story of geology, mining, and metallurgy to millions of visitors a year. Although patterned to some extent

Jan 1, 1932

By I. C. Edwards, G. E. Agar

INTRODUCTION Many research efforts over the past years have been devoted to the study of energy consumption in comminution and the characteristics of the broken material. The old "laws" have been superseded by more general methods of analysis1,2,3 but these methods have not received much attention outside the laboratory. The work to be described here was done in order to obtain scale-up information on wet rod milling of sylvinite. EXPERIMENTAL A 30 x 51 in. Denver rod mill with a scoop feeder was used for these tests. Ore was fed from a variable speed screw conveyor into the feed box along with saturated brine. The mill was filled to approximately 45% of its volume with 2400 lbs of a mixed rod charge. The minimum possible feed rate was 2.5 tph and the practical maximum for this mill was 8 tph. Individual tests were run by setting the solid feed rate, then adjusting the brine flow rate to give the desired pulp density. After steady state, as evidenced by constant discharge pulp density, had been reached, samples of the discharge were taken at 15-minute intervals. These samples were filtered, washed with alcohol, dried, then screened on Tyler screens using a Ro-tap shaker. The sylvinite feed was regular plant feed that had been scalped at 20 mesh and was tapped from the coarse ore bins. It had been previously passed through a roll crusher set at 3 inches and after scalping was essentially minus 1 in. plus 20 mesh. RESULTS The screen analysis of samples from each series of tests was plotted on double logarithmic scale paper to determine the reliability of the series. In some cases, a faulty sample or screening procedure dictated that the results of one test be discarded. The criterion is a simple one — if the slope of one plot was noticeably different from the others in the series, it was discarded. The only cases that caused difficulty were those in which the brine was not thoroughly displaced from the solids. When this occurred agglomerates were easily identified on the screens and the whole of the sample was retained on 3 or 4 screens. There were no border line cases. The number N given in Table 1 is the number of size analyses that were pooled to form the data shown in Fig. 1. While examining the reliability of the sizing and sampling by plotting the data, it became apparent that there was no significant difference between grinds made at 50 and 60% solids. For the analysis given here, these tests were regarded

Jan 1, 1967

By E. E. AGGER, Arthur Notman

THE proposal has been made in a bill introduced into Congress at the last session by Representative Jones of Michigan that an import duty of 6 c. per lb. shall be placed on copper. This action is urged after eighty years of prosperity for the industry in this country; during most of which copper has been on the free list, and during all of which a tariff would have been without real effect. To comprehend the general situation upon which this action would be imposed, we must refer to the past history of the industry and its trends at the present time. The following table supplies us with a picture of the physical growth of the industry in this country and its relation to that of the world as a whole down to Jan. 1, 1921:

Jan 1, 1925

By Henry D. Hibbard

I. INTRODUCTION. THESE impurities are perhaps the most important things in steel-especially steel made by the oxidation processes-the effect of which has not been at least approximately determined. By oxidation processes I mean the Bessemer and Siemens-Martin, during which the metalloids in the charge are removed by oxidation. It has been truly said that it is a clear advantage to have a new name for a new thing. To secure this and to economize space, let us adopt the name sonim (plural sonims) to designate the solid non-metallic impurities existing in steel or other metal. I would define a sonim as a solid non-metallic portion of matter existing as an impurity in metal. A piece of sand, brick, clay, or such material, imbedded in metal, would be considered as a foreign body, not as an impurity, and therefore not a sonim. The studies of sonims of which the results have been published hitherto, have been made chiefly or wholly on finished or at least on cold steel, without much, if any, regard to the specific methods by which the steel was made. While many of the results so obtained are valuable, they give little help in determining the cause, effect, or cure of the disease. It is not enough, in such a study, to know merely the commercial name of the process; for within the field of each process lies a great number of possible variations, each of which will yield a result differing in some respect from all others; and the control of sonims is particularly dependent. on the metallurgical treatment of the metal, because of the inability of analytical chemistry to throw much light on their presence, condition, and effect, as they usually occur in commercial steels. The microscope aids more, perhaps, than chemistry in their study.

Apr 1, 1911

By F. Brons, V. E. Marting

In the past, other authors.1, 2 have studied the influence of a skin effect on the productivity of a well. This skin effect, expressed by the skin factor S, is considered to be caused by a thin layer of impaired permeability immediately around the wellbore and extending vertically over the whole productive interval penetrated by the well. The skin factor S is defined as follows. Based on this, the impairment in productivity caused by a skin can be expressed by the fractional loss in productivity I, which is the loss in productivity divided by the total unimpaired productivity. For compressible flow in a stabilized well which drains a circular area of radius re, 1 is given by The present paper deals with a different kind of productivity impairment. Consider a well in which part of the productive formation is blocked off completely, either by incomplete penetration or by exclusion of parts of the productive zone by blank casing. In Fig. 1 (A, B and C), three examples are shown. Fig. 1(A) shows the situation where a well only partially penetrates the formation. This often is done to combat the actual or imagined danger of bottom-water coning. Fig. 1(B) shows a well producing from only the central portion of a productive interval. This type of completion is sometimes used where both water and gas coning are a problem. Although the case of a well producing through perforated casing cannot be treated in a manner similar to the previous two cases (where radial flow in the horizontal plane is assumed), Fig. 1(C) shows several intervals open to production and qualitatively describes this case (as will be discussed later). To study the loss in productivity in all these cases, two parameters are introduced which fully determine the impairment. The first is the penetration ratio "b," i.e., the total interval open to fluid entry divided by the total thickness of the productive zone. The second is the ratio hlrw. In this ratio, rw is the wellbore radius. The definition of h is more cumbersome. In Fig. 1(A), h is the thickness of the total productive interval. The streamline configuration for this case of partial penetration is basic to the other two cases considered (Views B and C of Fig. 1). It will be obvious from Fig. i (A) that the flow lines in the uppermost portion of the formation will be essentially horizontal, while those in the lower portion will curve upward toward the well. In Fig. 1(B), with only the middle portion of the zone open to production, the streamline configuration. of the upper half will be an exact mirror image of that in the lower half of the zone. Hence, for the case illustrated in Fig. 1(B), h is defined as one-half the total sand thickness. It follows, then, that in Fig. 1(C) h is one-half the distance between corresponding points in adjacent intervals. (In gun-perforated casing, h would be one-half the distance between perforations.) In a paper by Nisle4 and a paper given by the present authors5, the mathematical theory was developed for the cases under consideration. In the present publication, the emphasis is put on the results of these studies; consequently, the equations derived in Refs. 4 and 5 will be omitted, for the most part. The pressure drop p in a well producing from only a portion of the total formation thickness can, in analogy with Eq. 1, be expressed by Numerical solution of Eq. 5 by use of the IBM 650 leads to the following important conclusions. First, during a short period after starting production (usually on the order of a few minutes), the function p(b) is given by

By Carel Robinson

THE little coal mine at Otsego, in the Winding Gulf field of southern West Virginia was dying. In the history of coal mining thousands of mines have been successful at first, but usually a change occurred and profits ceased. Often be change was so gradual and extended over such a length of time that the fundamental causes did not stand out in sharp relief and their significance was not realized. Studies often reveal that the cause for failure was in the arteries that connect the producing places with the mine entrance. Profits continued so long as the working places were close to the tipple and while the thrill of newness aid ease of access resulted in effective supervision from day to day. The air- way and haulageway, the wire line and manway, may have been sufficient when the distance from the entrance was a few hundred feet, but were inadequate when this was extended for thousands of feet.

Jan 1, 1937

By A. W. Gauger

DESPITE many handicaps and in the face of many discouragements anthracite and bituminous coal producers continue to supply the needs of the nation now vastly multiplied by the demands of the greatest war of all time, total output being about 620,000,000 tons of bituminous and 64,445,000 of anthracite. The progress made by this industry during the national emergency reflects more credit on all connected therewith than will ever be given. Not only has the industry been called upon to produce more coal than ever before but it has also sent representatives to England to study and advise on methods for increasing production there, and has co-operated with other Allied Nations by welcoming engineers sent to this country to study American practice. One noteworthy development has been the growth of strip mining in the

Jan 1, 1945

WE the undersigned, being all persons of full age and citizens of the United States, and a majority residents of the State of New York, desiring to form a corporation pursuant to the provisions of the Membership Corporations Law for the purpose of incorporating, as provided in Section 6 of Article I. of said law, the existing unincorporated association known as American Institute of Mining Engineers, do hereby make, acknowledge and 6le this Certificate for that purpose, and do Certify as follows: I. That the American Institute of Mining Engineers is an unincorporated association organized and existing with the object of promoting the arts and sciences connected with the economic production of the useful minerals and metals and the welfare of those employed in these industries by means of meetings for social intercourse and the reading and discussion of professional papers, and to circulate by means of publications among its members and associates the information thus obtained. 11. That the persons duly appointed or designated to manage the affairs of said association are designated by the rules thereof Members of its Council; that the under- signed are all members of said Council as the same was constituted on the 29th day of December, 1904.

Jan 1, 1942

By Hugh H. Waesche

OF all the military services, the Signal Corps is the most concerned with piezoelectric minerals because of its function as a supply service to the strategic and tactical military forces. Consequently this paper is written from the point of view of one associated with that organization. The Signal Corps is responsible for the research, development, and supply of communications, radar, and components to the using services of the Department of the Army and to some extent the other branches of the National Defense Department. Their work therefore includes the study of the sources, characteristics, and application of quartz and other piezoelectric materials. These materials have become a vital consideration in strategic planning and are essential for efficient tactical operation by all the Armed Forces. The Signal Corps at the beginning of World War II was responsible for both Army Ground and Air Force electronic equipment. Since that time this Army service organization has probably done more in the development of frequency control devices using piezoelectric materials than any other group.

Jan 1, 1949

By Lawrence Adler

The authors are to be complimented on using a novel and potentially helpful technique to analyze the effects of mine roof trusses. However, some criticisms of their application and analysis seem appropriate to further its acceptance. This discussion will deal with the normal structural analysis format covering: 1) material. 2) load, 3) structure, and 4) analysis. It will then briefly review the testing procedures and finally cover miscellaneous items. That the analytical and testing results admittedly disagreed by several orders of magnitude, indicates a need for improved understanding. The introduction of data determined previously was not assisted by references to "Interim" or "Preliminary" reports. This material should have been concisely reformulated for the open discussions that Transactions encourage. In addition, many important simplifying assumptions are tacitly made without recognition, and much less, an attempted justification.

Jan 1, 1979

By N. V. Hansell

l. INTRODUCTION. THE last few years have shown an increasing interest in the subject of beneficiating iron-ores -in all iron-producing countries. In the United States, this movement has been slower than in certain parts of Europe, for the obvious reason that the abundance and relative cheapness of the Lake Superior iron ores has hindered the development of enterprises for the preparation of low-grade ores. Gradually, however, conditions have changed. The world&apos;s consumption of iron is increasing enormously. Being in 1900 about 40,000,000 tons, in 1910 ii was already 60,000000; and there is no reason to doubt that for the near future the increase in iron-consumption will continue at the same rapid rate, especially with, the development of China, certain parts of Africa, and other regions which have hardly been touched as yet by modern industrialism. It is. therefore, not surprising that apprehension is felt that the known available iron-ore resources of the world are gradually being depleted. Signs of this feeling are the recent investigation, under the direction of the U. S. Geological Survey, of the iron-ore resources of the United States, and the estimate presented to the last International Geological Congress, at Stockholm, Sweden, of the iron-ore resources of the world. These investigations have emphasized the fact that the known high-grade ore-deposits are limited in extent, and will, at a not distant future, be exhausted, compelling the iron industry to depend for raw material on the enormous deposits of low-grade ores which are distributed over almost all the world. The discovery of new deposits of high-grade ore, in countries not yet thoroughly explored, will not materially change this prospect. Of course, the part which such new deposits will play in the future cannot be forecast. The difficulty and cost of transportation will probably exclude many of them from use at the present centers of the iron industry.

May 1, 1912

By C. A. Stetefeldt

FoR the convenience of those who do not care to enter into the details of this long essay, I begin with a summary of the most important results it presents. The extraction of silver by the lixiviation-process from ores which have been subjected to a chloridizing-roasting, is based upon the fact that silver chloride is easily soluble in solutions of sodium or calcium hyposulphite, and that silver is precipitated from such solutions by an alkaline sulphide, with regeneration of the hyposulphite salts. In case the ore contains lead a large portion of the latter is and dissolved, lead sulphate being soluble in hyposulphite solutions. If, at the same time, copper is present, the sulphides precipitated from the solution, contain silver, copper, and lead, a combination of metals not desirable for subsequent treatment. Mr. E. H. Russell, of Park City, Utah, is the inventor and the patentee in the United States and several foreign countries of a new lixiviation-process, based upon the chemical facts discussed in this paper. Mr. Russell has discovered that lead can be completely separated from a sodium hyposulphite solution, as lead carbonate, by sodium carbonate or purified soda-ash, without precipitating any copper or silver. After decanting the solution from the lead carbonate, silver and copper are obtained from it in the usual way. This method of separating lead prohibits the use of calcium poly-sulphide as a precipitant for the sulphides, because any calcium entering the regenerated lixiviationsolution would also be precipitated as a carbonate with the lead by soda-ash. Hence, a sodium sulphide must be employed. A full investigation has demonstrated that this is by no means detrimental. Sodium sulphide and hyposulphite are more advantageously used in the lixiviation-process than the corresponding calcium-salts. Another defect in the lixiviation-process consisted in the necessity of a very perfect chlorination of the silver in the ore, because silver in

Jan 1, 1885

By Finlay, J. S.

THE North Lily Mine started its career in an unusual way it was discovered by a geologist. The remarkable circumstance of driving a 2400-ft. drift into an unexplored country and "hitting her on the nose," indicates that geologists are sometimes numbered among those whom the Lord loves. Diamond- drilling from surface had previously shown the presence and position of the Ophir beds, and surface showings of pebble-dykes, faults, and bleached rhyolite indicated conditions similar to those at the Tintic Standard "Pot-hole." The discovery drift from the Tintic Stand- ard 700-level reached the North Lily orebody in January, 1926, and development and stoping were continued by Tintic Standard men and equipment until the North Lily shaft was sunk and put into service in May, 1928. The discovery drift was run on a cooperative basis by the Tintic Standard and North Lily mining com- panies. Finding the North Lily mine cost the North Lily company $26,000. The Tintic Standard Mining Co. furnished men and equipment to drive this discovery drift at a fraction of what it would have cost to find the orebody from surface. This was the beginning of the friendly cooperation that still exists. Through Tintic Standard ground the Tintic Standard paid two- thirds of the cost and the North Lily one-third; the cost of the drift through Eureka Lily, into North Lily ground, was paid by North Lily. Later, another drift from the Tintic Standard 900-level was run on the same plan, excepting that Eureka Lily paid its share of the cost; that is, the Eureka Lily paid one-third of the expense in Tintic Standard ground, and the Eureka Lily two-thirds and North Lily one-third in Eureka Lily ground. This 900-drift was driven by North Lily from the Eureka Lily line to near the North Lily west side-line. From this point the Chief Consolidated continued the drift well into Tintic Bullion ground.

Jan 1, 1929