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By John A. Bonucci

AMAX Base Metals R&D, Inc. has developed technology for extracting and recovering platinum and palladium from spent automobile exhaust emission control catalyst. Our most promising route is a chloride-based hydrometallurgical flowsheet in which catalyst pellets or crushed monoliths are leached in HC1 with an oxidant at 95°C without agitation. Alumina co-dissolution can be limited by thermal pre-treatment of the catalyst. The leach solutions are treated by one of several precious metals recovery techniques to produce a high grade PGM concentrate. For the new generation of three-way catalytic converters which contain rhodium, an H2S04 preleach could selectively extract much of the rhodium while leaving the platinum and palladium behind. Capital and operating costs will be discussed.

Jan 1, 1984

By Ronald E. Versaw

Environmental legislation, both existing and proposed, requires that mills, tailings dams, evaporation ponds, and related processing facilities be located, constructed, and operated within stringent guidelines. An early step in planning a new processing facility is performing a site selection study in which topographic, hydrologic, geotechnical, and environmental parameters are evaluated for several alternate sites. Once a site is selected, then an environmental report, including a description of the proposed action, alternatives, baseline surveys, and discussions of potential environmental impacts, mitigation measures and monitoring programs is required. The federal legislation, siting studies, and environmental studies (along with the implications of these as they affect design) are discussed. In addition, costs for performing these studies and implementing control of effluents are discussed.

Jan 1, 1978

On Friday, Jan. 17, the thirteenth impression of the Perkin Medal was presented to Dr. Frederick Gardner Cottrell, at a meeting of the New York Section of the Society of Chemical Industry, held at the Chemists' Club, in New York City. The presentation address was delivered by Dr. C. F. Chandler, Senior Past President of the Society. The medal was awarded for the recipient's work in the electrical precipitation of suspended particles in gases. Dr. Cottrell's career, which is so familiar to members of the Institute, was sketched by Dr. Chandler. He told at some length of the experiments leading up to the final solution of electrostatic precipitation, which has done so much to solve the problem of smelter smoke. The principal interest in Dr. Cottrell's speech of acceptance lay in his remarks about helium, the production of which has been so reduced in cost that it has practically supplanted the use of hydrogen for inflation purposes in war balloons. He said: "Two or three weeks after war was declared in 1917, Dr. R. B. Moore attended a meeting of the American Chemical Society in Kansas City. At the general session, Mr. Seibel of the University of Kansas, gave a paper on krypton and xenon in some of the natural gases of Kansas. At the end of his paper, he expressed regret that at such a time, when everyone was thinking of war problems, his paper was of a purely scientific nature and had no practical bearing on the war. Dr. Moore immediately got up and said that he did not agree with Mr. Seibel. The presence of helium in those wells could, and should, have a very practical bearing on the war, as this gas could be extracted in quantity from the natural gas and used for balloons and Zeppelins. He pointed out some of the natural advantages of helium over hydrogen, and quoted Sir William Ramsey's letter advocating the use of helium for airships. The general attitude of those present was one of scepticism, so he finally asked Dr. Cady for his opinion who stated that he believed-the thing could be done, but was very doubtful whether it could ever be made practical on account of the cost." Dr. Moore in a letter wrote: "That same day I talked to Dr. Parsons, who was present at the meeting and was returning to Washington almost immediately. I told him what had happened, and that I believed the matter should be taken up by the Bureau at once and presented to the War Department. He promised to do this as soon as he got to Washington; and I know that he did take the matter up with other Bureau officials." Dr. Cottrell continued in part: News of Ramsey's suggestions also reached this .country through other channels and eventually came to our attention. Professors Satterly and Patterson of the University of Toronto commenced experimentation of the subject Jan. 1, 1916. Col. G. A. Burrell, who headed the research department of the Gas Warfare Service at the American University, tells me that Cady's experiments had also suggested similar possibilities to him.

Jan 3, 1919

By H. T. Clark

NO previous determinations of the deformation or recrystallization textures of titanium or of titanium-base alloys have been reported in the literature. The room-temperature structure of titanium is hexagonal close-packed with a c/a ratio less than 1.633. It would be expected, therefore, to have a rolling texture similar to that of other hexagonal close-packed metals, namely (0001) [1010]. Burgers and Jacobs1 have shown that zirconium, a metal isomorphous with titanium in its structure and similar in many of its properties, has such a texture with a scatter of the basal plane toward the transverse direction. This scatter is in the opposite direction from that found in magnesium by Bakarian2 but similar to that reported by Smigelskas and Barrett3 or beryllium. The rolling and annealing textures reported here for high-purity iodide titanium are significantly different from the . textures of any other hexagonal close-packed metal. All titanium used during this investigation was prepared by the iodode process." The annealed hardness of this material varied from 73 (material used for sample No. 2) to 97 Vickers hardness number. An estimate of the chemical composition of this grade of titanium has been reported by Finlay and Snyder.5 With one exception, shown in table I, the as-deposited titanium was cast into 10 to 20 g ingots in an electric arc furnace in purified argon before being rolled to sheet. The cast ingots were forged and ground until their cross-section was approximately rectangular, annealed 1 hr at 700°C in vacuum and cold rolled. Rolling was carried out in a two-high, 4 in. diam mill, using reductions no greater than 10 pct per pass. The direction of rolling was reversed after each pass, and, in order to avoid temperature effects, the sheet was allowed to cool after each pass. Unless the rolled sheet was sufficiently thin for X-ray penetration (about 0.004 in.), it was reduced to this thickness by pickling. Because of the possibility of introducing twinning or other deformation during grinding, no attempt was made to maintain uniform thickness of the sample during pickling by intermediate grinding or sanding operations. Those samples to be used for determining the annealed texture were recrystallized by vacuum annealing the cold-rolled sheet for 1 hr at 500°C. These thin samples were held between thick titanium sheets during annealing to prevent distortion. Table I outlines the rolling and annealing schedule of those samples for which photograms or texture patterns are shown. X-ray Techniques The usual techniques for determining textures were employed during this work. Molybdenum radiation was used for the transmission exposures and copper radiation for the glancing angle ones. Since titanium fluoresces under these conditions, it is necessary to employ a filter between the sample and the film. The Kß radiation filters are very satisfactory for this purpose. Sufficient grains having favorable orientation were present in both the cold-worked and in the cold-worked—500°C annealed samples to provide satisfactory patterns with the samples stationary. Because of the difficulties of comparing intensities of transmission photograms with those obtained

Jan 1, 1951

By F. H. McDowell

The electro-magnetic separator of Mr. G. Conkling, Glens Falls, N. Y., described by Mr. Birkinbine* in a paper at the New York meeting of the Institute, in February, 1889, has been in successful operation at the Tilly Foster 'mine for a considerable period, under the disadvantages which seem to be the inevitable attendants of pioneer enterprises in new technical fields. The results of a run of several months, which the Superintendent, Mr. S. P. Tomkins, has taken pains to collate, are here presented by his courteous permission, and that of Mr. E. S. Moffat, the energetic and skilful General Manager of the Lackawanna Iron and Coal Company, to whom our profession is already indebted for examples of bold and ingenious practice in mine-engineering. It is believed that these figures will assist those who are planning similar operations to decide intelligently what they may, and, more important still, what they may not, expect to accomplish. The local difficulties in the way of this experiment at the Tilly Foster mine were many and great. Only about two-thirds of the waste-dump, resulting from the assorting of previous years, is ore; and this varies in content of iron from 20 to 28 per cent. The remainder is rock, some (from horses in the vein) showing particles of adhering mineral, some (from the foot- and hanging-walls) entirely barren. The expense of overhauling the dump and removing this rock is by no means the least of the numerous items which must be charged against the concentration. Associated with the lean ore are hornblende and other minerals, carrying iron in the non-magnetic state, which must necessarily be washed away with the tailings. The waste-dump was originally located without reference to future treatment, and now can only be handled by means of a locomotive,

Jan 1, 1891

By Arthur S. Dwight

The profeseional career of Thomas Septimus Austin, who died at El Paso, Tex., Aug. 23, 1906, was contemporaneous with the growth of the silver-lead smelting-industry of the Far West, to which his talents and zeal contributed in no small degree. Born at Stratford, Conn., Dec. 7, 1853, he was the seventh son in a family of thirteen. His parents were well-to-do; and he received a thorough preliminary training at the Hopkins Grammar School, New Haven, Colin., passing thence to the Columbia School of Mines, in New York, where he was graduated in 1876. His first professional work was that of analytical chemist with a Cuban sugar company. In this position he spent a year, and, whatever else of benefit he may have acquired during that year in Cuba, he gained a facility of speech in the Spanish language which was of inestimable value in his subsequent work in Mexico and the southwestern United States. In 1877, he went to the Rocky Mountains, and, under the firm name of Murphy & Austin, opened an assay-ofice in Lead-ville, Colo., which was just then coming into public notice as a rich silver-lead camp. The next year, however, he entered the service of the Germania Smelting & Refining Co. at Salt Lake City, Utah, where he remained until 1882, first as assayer and chemist, and later as Assistant Superintendent. The Germa-nia bears the honorable distinction of being one of the first of the large " custom" lead-smelters erected in the West. Its founders may be called the pioneers of the modern lead-smeltr ing practice, and the Germania served, to a large extent, as a model for the many plants that sprang into existence during the next few years in Utah, southern Idaho, Colorado and other lead-producing districts. The formulation, for the first

Jan 1, 1908

By Horace H. Emerich

PrePatory Note.—The first part of this paper was sent to me by Mr. Emrich nearly nine months ago; and I held it, waiting for the second part, which he had promised to forward soon, so that I might submit the whole to some of his former professional associates, and advise him of their criticisms and suggestions before off'ering his work to the Institute. But, five days before the second part reached me, I received by telegraph the news of Mr. Emrich's sudden death. The paper has therefore not had the benefit of such a revision by the author as might have made it ill some respects clearer and more cornplete. Nevertheless, I believe that experts in the branch of metallurgy with which it deals will find it both original and suggestive.—A. Eilers. I. Partial ReFining iN the ANode-Furnace. During my connection with one of the large New Jersey copper-refineries, and probably before that period, from 15 to 30 per cent. of the copper-bullion received was the very foul, leady blister-copper produced from lead blast-furuace matte. It had been customary to mix a small part of this blister with each charge of purer pig-copper, in the effort to dilute it as much as possible before casting into anodes; but tank-house conditions were such that I was led to try making entire furnace-charges of this blister, and refining it as much as possible in the furnace—afterwards casting to anodes and refining elec-trolytically, in tanks and solution separate from the main bulk of the purer copper. In making this experiment, notes were made, for several furnace-charges, of everything thought to have a bearing on the question, and some interesting facts were brought out, both in the furnace-working and afterwards in the tanks.

Jan 1, 1913

By M. A. Hosmer, Job Goostray, R. F. Harringon

In this paper, as in so many discussions of an historical nature, there is little chance for original material and much has had to be rewritten from older papers, documents, accounts, reports, and the like, some of which are of doubtful authorship or contain conflicting statistics. Fully aware of these pitfalls, the authors have tried to quote the origin where possible, and also to seek further confirmation when the statement warranted it, but they cannot assume responsibility for certain facts and dates. The Encyclopedia Britannica was frequently consulted. The authors wish to acknowledge assistance from Mackintosh-Hemp-hill Co. (formerly the Fort Pitt Works) and also from officials of the Watertown Arsenal who loaned valuable books and gave much necessary information. They are particularly indebted to Colonel Dickson of that institution. The data on modern guns were furnished by Mr. F. Brauer of the Watertown Arsenal; Mr. H. S. Chaffee assisted by obtaining records and data of work carried on by the Builders' Iron Foundry of Providence, R. I. Three Epochs in History of Cannon Among the great industries of New England, the manufacture of iron was the first to receive attention. Iron ore in considerable quantities was known to exist within the territory of the Massachusetts Bay Colony; and as early as 1629 some steps appear to have been taken toward the manufacture of iron by the Court of Assistants in London, under whose patronage the colony was founded. During the next ten years, deposits of bog ore were found in numerous ponds in the Plymouth Colony; and, in 1652, iron manufacture was begun at Raynham. The "Old Colony" was known as the main seat of this industry in New England, out of which grew a concern which was later to become one of the principal

Jan 1, 1925

By Kenneth Cottingham

The number of wells drilled in Ohio in 1943 was slightly in excess of the number drilled in 1942. Compared with the average annual completions for the five years preceding, the year 1943 was short 11 per cent, hut the average initial volume of gas wells was considerably improved. In 1942 the average initial open flow per gas well was 668 M cu. ft., whereas in 1943 the average was 913 M cu. ft. Although no large gas-producing areas were discovered during the year under review, some 30 small pools were found in 17 of the counties of eastern Ohio. These new pools averaged about 300 acres each, and most of them were not extensions but were separate pools adjacent to older production. The Clinton sand furnished most of these discoveries, although six were from the Berea, one was Newburg, and three were shallow sands. No discoveries were made outside former producing counties, and there was no new development the Trenton area of western Ohio. The number of oil wells decreased from 181 drilled in 1942, to 170 in the year 1943. The production of Pennsylvania-grade oil increased 7644 bbl. The total Corning production, however, decreased 91,325 bbl. The present price of Corning-grade oil, $1.31 per bbl., is too low, in the opinion of the operator, to justify exploration. Until something is done in correcting the price level of Corning grade, the production probably will continue to decline. The oil industry in Ohio is making a concentrated effort toward increased production and improved methods of recovering Pennsylvania-grade oil, and a.s this report is written a research and engineering program is being formulated for the benefit and information of the various producers of that grade in Ohio.

Jan 1, 1944

The following is an incomplete list of members and guests who called at Institute headquarters during the period July 10, 1919, to Aug. 10, 1919. Howard C. Arnold, Washington, Pa. J. S. Lane, New York City, N. Y. L. M. Banks, Denver, Colo. H. W. Lawrie, Washington, D. C. George S. Blair, Pittsburgh, Pa. J. L. McAllen, Latouche, Alaska. Richard H. Catlett, Newark, N. J. David F. McFarland, Urbana, Ill. George L. Clark, Council Bluffs, Iowa. James F. Magee, Lancaster, Pa. Capt. Frederick S. Cook, Portland, Ore. A. G. McGregor, Warren, Ariz. John J. Croston, Atlanta, Ga. Emory M. Marshall, Santa Fe, N. M. Thomas Davis, Seattle, Wash. Benjamin L. Miller, Bethlehem, Pa. J. C. Dick, Salt Lake Cite, Utah. 2d Lieut. C. 0. Noble, U. S. Army. Chris. G. Dobson, Vancouver, B. C. Irving Perrine, Hutchinson, Kans. H. S. Emlaw, Grand Rapids, Mich. Fred S. Porter, Seattle, Washington. F. A. Fahrenwald, Cleveland, Ohio. Capt. H. R. Robbins, Peking, China Lieut. James L. Head, St. Louis, Mo. Joseph P. Ruth, Jr., Denver, Colo. A. A. Holland, Napanu, Canada. William A. Simkins, San Francisco, Calif. W. E. Hopper, Washington, D. C. T .V. Smirnoff, Siberia. Harry Hotchkin, Chicago, Ill. Harrison Souder, Cornwall, Pa. L. L. Hutchison, Tulsa., Okla. F. J. Sur, Denver, Colo. Paul S. King, Wilmington, Del. Harry Wolf, Denver, Colo. George K. Anderson, Jr., lies accepted a position as manager for Wight & Co., producers of air-cooled blast-furnace slag, at Longdale, Va. J. M. Armstrong, with the Caribbean Petroleum Co., has been transferred from Philadelphia to Maracaibo, Venezuela. Fred Sherman Baker, who has been with the Oriental Consolidated Mining Co., at Unsankinko, Chosen, Korea, is now at Columbia City, Ind. Ray J. Barber has removed from Roxbury, Mass., to New York City, and is now consulting engineer for the Roxbury Cold Mines, Inc.

Jan 9, 1919

By P. Martignan

THE year 1923 has seen new developments in the only French wells, i.e., those of Pechelbronn, Alsace. The output of the two pits now in operation totaled more than 75,000 tons, although there was a two months' strike. It is expected that 1924 will see an output of 85,000 tons; and 1925, 100,000 tons. A new pit has just been put in operation (fourth pit; the third not being in operation). The oil and the oil sands are extracted at a depth of 350 meters. Special attention has been given to the development of the distillation and refinery plants, particularly the manufacturing of lubricating oils. The present output of the lubricating-oil factories is approximately 20,000 tons neutral oils; 20,000 tons spindle oils, together with 2000 tons of paraffin. Engineers are introducing the most modern American processes of refinery and distillation. The company has 3000 employees. The capital of the company has just been increased from 45,000,000 francs to 81,000,000 francs. Some other drilling has been done in the Auvergne and Landes districts, and some oil has been found, but in too small quantities for commercial operation. Great hopes, however, are entertained of finding large quantities of oil, and the French Chambers have voted a special fund of 20,000,000 francs for investigating oil in France. Much work has also been done in the Colonies but without much success; oil is found in different districts of Tunis, but in relatively small quantities. In Morocco, drillings have not been successful. A prospecting mission recently returned from Madagascar gave an optimistic report concerning the oil conditions on the Island. Prospectings are being made also in French Indo-China. The present domestic yearly consumption is about: Gasoline 750,000 metric tons, kerosene 70,000 metric tons, automobile lubricating oil 75,000 metric tons.

Jan 3, 1924

By Kenneth Cottingham

The number of wells drilled in Ohio in 1943 was slightly in excess of the number drilled in 1942. Compared with the average annual completions for the five years preceding, the year 1943 was short 11 per cent, hut the average initial volume of gas wells was considerably improved. In 1942 the average initial open flow per gas well was 668 M cu. ft., whereas in 1943 the average was 913 M cu. ft. Although no large gas-producing areas were discovered during the year under review, some 30 small pools were found in 17 of the counties of eastern Ohio. These new pools averaged about 300 acres each, and most of them were not extensions but were separate pools adjacent to older production. The Clinton sand furnished most of these discoveries, although six were from the Berea, one was Newburg, and three were shallow sands. No discoveries were made outside former producing counties, and there was no new development the Trenton area of western Ohio. The number of oil wells decreased from 181 drilled in 1942, to 170 in the year 1943. The production of Pennsylvania-grade oil increased 7644 bbl. The total Corning production, however, decreased 91,325 bbl. The present price of Corning-grade oil, $1.31 per bbl., is too low, in the opinion of the operator, to justify exploration. Until something is done in correcting the price level of Corning grade, the production probably will continue to decline. The oil industry in Ohio is making a concentrated effort toward increased production and improved methods of recovering Pennsylvania-grade oil, and a.s this report is written a research and engineering program is being formulated for the benefit and information of the various producers of that grade in Ohio.

Jan 1, 1944

By A. Weiss

Operations Research developments within the mining industry have evolved over the last few years through stages typical of any new technique. By 1965, most companies had passed from mere recognition of the usefulness of operations research techniques to cautious acceptance of and, in some in- stances, to confident utilization of this relatively new tool. This is reflected in the growing interest and increasing participation of mining companies in sponsoring individual papers on the subject published in mining journals or presented in full sessions at annual meetings. Chief among the sources which served, in 1965, as a barometer for measuring operations research progress within mining is the Annual Symposium on the Applications of Statistics, Operations Research, and Computers in the Mining Industry, which is now sponsored by the University of Arizona, Stanford University, Colorado School of Mines, The Pennsylvania State University, and the Society of Mining Engineers of the AIME. Two significant trends were evident in the applications of operations research techniques to problems typical of the mining industry. On the one hand, unique and imaginative O.R. applications were being developed by several companies, government agencies, and at the university level. These techniques were usually developed to solve specific existing problems. On the other hand, there was unmistakable evidence of attempts to look for problems which could be solved with those "operations research" approaches which would involve the use of the digital computer. In the latter instance, solutions may become applications or demonstrations of how the computer can be used in the reduction and interpretation of data, without the benefit of a decision model. This is a common tendency as most companies have computers, at least in their accounting sections, and many operations research solutions require the use of a digital computer. From the applications observed in 1965 and in prior years, the successful techniques have evolved.

Jan 2, 1966

By Charles R. Keyes, D. F. Riddell

For a period of several years, and in a large number of oases, the Metallurgical Laboratories of the New Mexico School of Mines were employed in umpire work. During this time many important local problems mere solved. Against the results of careful chemical analyses of ores, assay-returns mere often checked. In many cases the assay-methods of mine and custom-smelter were compared, and both often found faulty for the ore concerned. A wide range of ores was covered. Many of the chemical analyses and assays were made by Dr. F. C. Lincoln, Professor of Metallurgy, now of the Montana State School of Mines. A varied series of instructive assays was prepared by Prof. R. B. Brinsmade, now of the West Virginia State University. Single assays and given series of tests were undertaken by H. T. Goodjohn, now chief chemist to the Cia. Metalurgica de Torreon, Coahuila, Mexico; by H. J. Hub-bard, now superintendent of the Butters Divisadero Mines, Jocoro, San Salvador, C. A.; by E. D. Morton, now superintendent of the Arizona & Nevada Copper Mining Co., at Lunning, Nev.; and by A. W. Edelen, now superintendent of the Angangueo Unit of the American Smelting & Refining Co., in Michoacan, Mexico. A critical comparison of assay-methods that were found to be followed in the case of certain gouge-ores mined in the Mimbres range in New Mexico, and about which there had been much controversy, was made by D. F. Riddell, then Acting Professor of Assaying, and now superintendent of the Providentia Mines Co. of Parral, in Chihuahua, Mexico. To him is due the credit of much that is contained in the following notes, which he has generously permitted to be used in advance of the publication of the complete results.

Jan 1, 1912

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

This story of the salting of a supposed diamond mine is a part of our Western history and deserves to be recorded in this book. It was more than a local affair, because it was concerned with persons in London and New York, as well as San Francisco. Part of the story has been told by Asbury Harpending in a little book published 12 years ago. Harpending (who died at New York in 1923) was in London in March, 1872, when he received a cable dispatch from William C. Ralston, the president of the Bank of California, stating that "a vast diamond field" had been discovered "in a remote section of the United States". Before starting for San Francisco, Harpending had an interview with Baron Rothschild, who showed a lively interest in the story, which was as follows: two weather-beaten prospectors went to the Bank of California and deposited some uncut diamonds and rubies for safe keeping; these precious stones were estimated to be worth $125,000. The men said that they had found the gems in "a desert portion of the West". They departed quietly, but the story was told in business circles; whereupon George D. Roberts, a mining engineer of wide experience and an associate of Ralston, sought an interview with the prospectors. One of them proved to be a man that had been in the employ of Roberts. Both prospectors, named Slack and Arnold, appeared "coy and cautious"; they were "simpleminded fellows", and were "afraid to trust anyone with the momentous secret ". They refused to divulge the place of discovery and declined "to part with their rights", but later "they became more amenable to reason" and expressed willingness to sell a half interest to

Jan 1, 1932

By Harry V. Warren

During the past few years the author has had an opportunity to examine a number of base-metal mines in the western United States, France and Spain. Nearly all of these mines produced some silver, and laboratory studies of the relationship between the silver and the various base-metal minerals in the ore have given some interesting and, it is to be hoped, enlightening facts. As this work was undertaken primarily to ascertain the amount of silver chemically associated with, not controlled by, the various base-metal minerals, the laborious and not always satisfactory method of picking out "pure" samples of each mineral from many localities was employed. However, the results obtained have justified the time that has been spent. Not only have the conclusions arrived at in different mining areas been in accordance with one another but in many instances they have afforded scientific support or explanations for much of the knowledge that operators in the various camps have acquired by practical experience. Although many of the conclusions are not new, many of the facts are, and the results, if they do nothing else, serve to confirm the findings of some of the other workers in this field, particularly the work of Nissen and Hoyt1 and of F. N. Guild2. Dr. S. G. Lasky3 has suggested a novel method for determining from a series of algebraic equations the amount of silver controlled by each of the base-metal minerals but I doubt very much whether his method can be justified, chiefly because there appear to be more variables to be considered than the few that appear in his equations. Typical Examples of Irregular Silver Distribution Combination Mine, New Mexico, U.S.A.—In this mine an examination of the assay plans either of the mine or of the average mill feed or products

Jan 1, 1935

By V. H. Wilhelm

The year 1936 was a prosperous one for the oil industry in California. Increases in crude prices were posted in February and March. Re-establishment of voluntary curtailment in February was a factor in holding production at an efficient level throughout the year. Reduction of storage was effected through adherence to curtailment measures, aided by greater demand and smaller average well completions. During the first six years of voluntary curtailment, allotments were increased during the summer season and reduced during the winter season. This year, good results were obtained through a revised system of allocation, by which the California monthly quota was held constant at approximately 540,000 bbl. per day. After a 7-month period of practically unrestricted production (ending in January 1936), numerous operators found that curtailment was still necessary, as California and export market,s were not yet capable of absorbing the state's potential production, which was estimated to be in the neighborhood of 850,000 bbl. per day. Therefore, in February California operators again placed themselves under voluntary curtailment; with the result that state production dropped from around 700,000 bbl. per day in January to a low of 565,000 bbl. per day in April, and increased gradually to around 585,000 bbl. per day for December. Drilling activity during the year increased about 10 per cent over that of the preceding year, although the resultant production per well decreased. Field Discoveries As a result of a very active wildcatting campaign in California, aided by better interpretation of geophysical data, five new oil fields and two new gas fields were discovered. Oil Fields Greeley Field, Kern County.—The Standard Oil Co. added to its list of djscoveries by drilling and completing its K.C.L. No. 11-1 well at a

Jan 1, 1937