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By R. W. Smith. Discussion by D. Watson, R. M. Manser

D. Wotson, R. M. Monser (Watten Spring Laboratory, Stevenage, Herts., U. K.) - This is a valuable and interesting paper and will make an important contribution to the development of a general theory of silicate flotation. In particular the dominance of surface reactions which produce fluosilicic acid and its ions has been convincingly demonstrated. In a paper to be published shortly, however, we offer some evidence which is not consistent with the feldspar activation theory proposed by Prof. Smith. This theory, given in Eqs. 17-20, suggests that activation takes place through the exchange of SiF6 ions for OH- at aluminum sites. This results in a negatively charged site facilitating adsorption of RNH3 Firstly, we have determined the flotation response (using the vacuum flotation technique) and the adsorption of dodecylamine on a natural feldspar (albite) and on the same feldspar after washing with perchloric acid at pH3. This pre-treatment was shown to remove surface adjacent aluminum atoms. It was found that although the acid washed feldspar floated much less easily than the untreated sample, the function of fluoride ion - giving activation over the pH range 4-6.5-was preserved. Moreover, the amount of dodecylamine adsorbed either with or without fluoride present is little affected by acid-washing, despite the depression caused by this treatment. This suggests that surface aluminum atoms can be of little importance in the fluoride activation mechanism. Secondly, we have determined the changes in solution concentration of F- and H+ (or OH-) accompanying reaction of the surface with fluoride ion. The ratio of H+ lost from solution to F- lost is high, ranging from 6.9 at pH4 to 1.0 at pH 7.5. This is consistent with reaction of HF (6 molecules for every Si removed) at the surface, producing SiFi-ions, but not with the re-adsorption of these ions.

Jan 1, 1967

By E. E. Malouf

With the continued development of low-grade porphyry copper deposits by open pit mining, substantial amounts of copper-bearing strip material have been accumulated in waste dumps adjacent to the many large mines. Since the end of World War II, the production of copper from leaching these copper-bearing wastes increased from approximately 4% of the total copper production to 10% by the early 1960's. Projected increases will probably raise this figure to 20 to 30% by the early 1970's. Furthermore, a gradual recognition of the economic feasibility of leaching mined-out areas is evident and will undoubtedly contribute additional production. Waste dumps in canyons and gulches on the periphery of open pit mines, mine stopes, caved areas, and abandoned open pits often contain substantial quantities of leachable rock ranging in concentration from 0.1 to 0.4% copper. Recent developments in the leaching of copper, mainly the recognition of bacterial oxidation of sulfide minerals combined with better under- standing of the control of the salt content of the leach solutions, both by adjusting the pH and/or by hydrolysis, are resulting in a greatly expanded recovery of copper from these hitherto uneconomic mine rejects. 11.5-1. Mechanism of Leaching. Leaching processes for the extraction of metal values from mine ore or waste may be classified for convenience as either chemical leaching or bacterial leaching. Chemical leaching is considered to be the extraction of soluble salts by metathesis in acidic, basic, or neutral water solutions. The reactions involved may be evaluated by chemical thermodynamics. Bacterial leaching, although a chemical process, is dependent on biological catalysis and this is generally a much more complex process. This justifies its separate treatment in the application to leaching. Acid ferric sulfate solutions are commonly employed in the mining industry to leach valuable metals from metal sulfide ores. The leaching mechanism is a reduction-oxidation reaction in which minerals are oxidized at the expense of ferric sulfate. Such chemical leaching is profitable when

Jan 1, 1968

By J. M. Glass, C. D. Sholtess

We at Hughes Tool Co. are extremely proud of the quality of the hardware and techniques introduced through our efforts in tunnel-machine development and of the ready acceptance of them by manufacturers and contractors throughout the world. All of us who attended the conference and who are represented in the book, we believe, anticipate an increasing need for improved methods of underground excavation. The development of such methods will permit the further exploitation of our underground resources plus providing underground space for transportation and habitation at a rate compatible with demand. We hope that our comments, derived from the application of Hughes Tool Co.'s rotary boring experience, may provide a better understanding of the boring method as a possible avenue through which the desired improvement in underground excavation may be attained. We hope you may also become aware of some of the problems Hughes, as a pioneer developer of raise, shaft, and tunnel-boring equipment, must face prior to further major undertakings in this very interesting field. Our task is to acquaint you with the present status of the Hughes Tool Co. development program as it relates specifically to tunnel-boring machines. We feel this task can best be accomplished by a brief review of the general sequence of events leading to and constituting an equipment development program and more specifically the manner in which these events have occurred to either influence or further our boring-machine development program. The development of a machine to accomplish a certain function or series of functions is usually a very long and tedious process to which any number of individuals must contribute, perhaps over a period of centuries. Of particular irony is the fact that often those who contribute most generously do not necessarily reap the greatest immediate benefit. A marketable ma- chine will, however, result from a sequence of events such as these: 1) A problem or need is defined. 2) An idea is born to eliminate the problem.

Jan 1, 1970

By V. (“Viv”) R. Forbes

[ ] INTRODUCTION "The Liberal Party believes that the State's mineral resources belong to the people of Queensland and therefore it is essential that the state, on their behalf, obtains maximum benefit from the development of those resources." (Liberal Party, 1980 "Mineral Resources Policy" p.2). "Unless sound policies are implemented.... increased production of minerals will benefit only the already wealthy and the lucky few... A resources tax is essential to ensure that above normal profits are shared by the whole community.... Labor policies on taxation must ensure an adequate return from mining developments to the Australian people." (Labor Party Policy Paper, May 1982 "National Issues relating to rapid expansion of mineral production during the eighties". p.1, 37, 47). Judging from these statements, key political parties in Australia believe that mining profits are lightly taxed and that shareholders get most of the benefits. THE REALITY The Government Share of Income statement in Table 1 attempts to measure the government share of the income generated by the "Big Five" Australian mining companies - Broken Hill Pty Ltd. (BHP), CRA Limited, Utah International, MIM Holdings Ltd., and Western Mining Corporation ("WMC"). These companies control over 70% of Australia's mining industry including all the most profitable mining operations. They dominate the mining and processing of iron and steel, aluminum, manganese, coal, oil and gas, copper, lead, zinc, silver, nickel, gold, ferro-alloys and salt in Australia. They are also major world exporters of most of these products. They are thus a representative sample of the profit-earning side of the Australian mining industry. In their two most recent financial years these five companies had income before tax of A$6,980 million. The Government share of this income was A$6,285 million or 90%. The total market capitalisation of the Big Five is about A$8,480 million. (December, 1982). Governments thus consumed the equivalent of 82% of their total value in just two years. This was taking place while the politicians drafted the above statements calling for an "adequate" share for the people.

Jan 1, 1985

By J. W. Whitlow, P. K. Theobald, W. C. Overstreet

Monazite placers in a region of the Carolinas ex- in 1951-1954 by the USGS are estimated to contain at least 53,000 short tons of thorium and 4600 short tons of uranium. None of these deposits is being mined. The 5200-sq mile area investigated extends northeast along the western Piedmont from the Savannah River in South Carolina to the Catawba River in North Carolina. Much of the region is 700 to 1100 ft above sea level. Gentle hills and broad interfluves give a local relief of 100 to 200 ft. This increases to 1700 ft at the west margin of the area where the east flank of the Blue Ridge is approached in South Carolina and the South Mts. are entered in North Carolina. This report is restricted to placers in the Piedmont. Monazite deposits in the Blue Ridge and coastal plain were not covered by the investigation. Monazite Mining in the Carolina Piedmont: Discovered in 1879 by W. E. Hidden,' the monazite placers in the Carolina Piedmont were first mined in 1886. The area was a major world source for thorium and the lanthanides until 1895, when Brazilian monazite entered the trade. Total output from the Carolina Piedmont has been nearly 5500 tons of monazite,2 but the placers have been idle since 1911, except for 48 tons produced between 1915 and 1917. Monazite mining was revived in the Carolinas in 1954 when a dredge operated by the Heavy Minerals CO. opened a fluviatile placer along Horse Creek in the coastal plain near Aiken, S. C. Geology and Mineralogy: Two recent papers",' have described the geology of the monazite placer district in the Piedmont between the Savannah and Catawba rivers; the general geology of the region has been reviewed by P. B. King.' These reports show that the placers are in locally derived alluvial sediments that cover the floors of shallow, narrow valleys in an area underlain by monazite-

Jan 1, 1960

By A. Q. Tool

THE necessity of accurate temperature measurements in the glass-making industries is today being much more widely appreciated than in the past. The introduction of the modern simplified and perfected pyrometric methods in connection with exact regulation of furnace temperatures has caused a marked improvement in the glass product with a quickened rate of production. An example of the processes in which much improvement has been and still can be made is that of annealing or heat-treating the glass. This is one of the most delicate processes in glass manufacture and one that requires a most careful furnace control. The heat treatment is undertaken to decrease the possibility of breakage and, in glass for fine optical instruments, to prevent serious warping of accurately ground and polished surfaces and to make the glass more uniform throughout to the passage of light waves. These objects are accomplished by removing all the harmful stresses that exist in a piece of glass when it has been cooled too quickly or unevenly. Such stresses exist, for example, after it has been pressed, cast, or otherwise worked. Thus the process of annealing consists of heating the glass evenly to the temperature at which it softens just enough to relieve these stresses in a reasonable time and then cooling slowly and uniformly until the glass hardens again. Accordingly, the things that must be investigated and determined in order to anneal glass without loss of time are, the annealing temperature, the time that the glass should be held at this temperature while the stresses relax, and the quickest cooling procedure that will give satisfactory results. After these characteristics of the glass are known the problem is one of pyrometry and temperature control entirely. In cases when it is known that a glass article will be required to withstand some definite type of heat or mechanical shock it is often possible, by a proper heat treatment, to produce such a distribution of the stresses in the glass that it will be enabled to resist these shocks more effectively.

Jan 9, 1919

By Peter N. Calder, Alan Bauer

INTRODUCTION One of the most important decisions involved in the design of an open pit mine is the selection of a slope angle. Despite this fact, engineering procedures have developed slowly in this field. Only recently have the instruments and know-how become available to undertake a design based on sound engineering principles. The effect of blasting on open pit slope stability is one aspect in which the state of the art has not developed fully. These effects include: a) the effects of the ground motion associated with blast waves on slope stability, and b) the fracturing of rock in the vicinity of slopes caused by blast waves. Natural rock jointing plays an important role in both of these. SUMMARY OF BLASTING EFFECTS In recent years there has been a trend to larger sizes of blast holes in open pits to the extent that today 9% in. and 12% in. diam. holes are the most common. The reasons for this have been economic. Larger machines are more efficient and produce at a lower overall cost per ton. As the size of blast holes have increased, so have the other factors associated with blasting. Bench heights have increased, the tons/ft. of hole yield has risen significantly and the explosive load per hole has increased. Quite naturally the rupture radius for a single blast hole has increased along with the vibration level produced per blast hole. Open pit blasting operations can result in two types of unwanted damage: 1. Damage to structures, such as buildings, dams and slopes by ground vibrations initiated by the blast. 2. Fracturing of ground beyond the planned excavation limits. Let us first consider item one. Vibration effects are determined by the type of blast which is fired and the type of medium through which the blast wave is being transmitted. They are strongly influenced by the weight of charge per hole, the number of holes per delay, the distance from the shot point, the mode of initiation, the point of interest relative to the blast, etc.

Jan 1, 1971

By Frank C. Greene

Drilling in Missouri in 1943 continued at a lower rate than in 1942, only 28 wells being completed. Following the completion of the Cities Service Oil Company's No. I Jim Cook near Tarkio, in the northwest corner, NW. 'fi sec. 32, T. 65 N., R. 39, W., Atchison County, four dry holes were drilled by other parties, all a mile or more from the Cook well. Later the Cities Service Oil Co, completed No. 2 Cook for 60 bbl. Table I gives a summary of activities by counties. The total footage drilled was 23,83134 ft., of which 12,802 1/2 ft. was by cable tools and 11,029 by rotary. Four of the dry holes were drilled into Mississippian or older beds.

Jan 1, 1944

The Pennsylvania State College, Mineral Industries Experiment Station, State College, Pa For publications address the Director The Pennsylvania State College through the Minerals Research Experiment Station has issued 10 Bulletins and three Technical Papers, from which the following have been selected as of greatest interest to mining engineers and geologists: Bulletin 1, An investigation of the properties of smitliing coals (1922), free; 2, Petrography of the Mica Pendotite Dike at Dixonville (1926), free; 4, The Helderberg Group from cen¬tral Pennsylvania to southwestern Virginia (1929), 25 cents, 5, Bentonite in Pennsylvania (1929), 10 cents, 6, Production data on Appalachian oil fields (1930), free; 8, Oil field waters of Pennsyl¬vania (1930), free; Technical Paper 2, Condition of water in coals of various ranks.

Jan 1, 1933

By Frank C. Greene

Drilling in Missouri in 1943 continued at a lower rate than in 1942, only 28 wells being completed. Following the completion of the Cities Service Oil Company's No. I Jim Cook near Tarkio, in the northwest corner, NW. 'fi sec. 32, T. 65 N., R. 39, W., Atchison County, four dry holes were drilled by other parties, all a mile or more from the Cook well. Later the Cities Service Oil Co, completed No. 2 Cook for 60 bbl. Table I gives a summary of activities by counties. The total footage drilled was 23,83134 ft., of which 12,802 1/2 ft. was by cable tools and 11,029 by rotary. Four of the dry holes were drilled into Mississippian or older beds.

Jan 1, 1944

Meeting, Apr. 25, 1913.-President Rand recommended the appointment of the Nominating Committee (see p. i), and a Committee on the Use of Electricity in Mines (see p. xliv), which committees were duly approved and appointed. President Rand recommended the establishment of. a Committee on Mining Methods, and requested authority for the President to appoint the members of this Committee, both of which recommendations were approved. The name of the Committee on Economic Geology was, at its own request, changed to the Committee on Mining Geology. The request of the Iron and Steel Committee, that a meeting of the Institute, under the auspices of this Committee, be held in the latter part of October, the place of meeting to be decided later, was granted.

Jan 5, 1913

Oct. 3, AIME, National Open Hearth. Southern Ohio Section, Deshler-Wallick Hotel, Columbus. Ohio. Oct. 10, AIME, Eastern Section, National Open Hearth Steel Committee, Harwich Hotel, Philadelphia. Oct. 15-17, Canadian Institute of Mining and Metallurgy, annual western meeting, Royal Alexandra Hotel, Winnipeg. Oct. 20-22, AIME, Institute of Metals Div., fail meeting with National Metal Congress. Hotel Adelphia, Philadelphia. Oct. 20-24, American Society for Metals, meeting with National Metal Congress, Benjamin Franklin Hotel, Philadelphia. Oct. 20-24, 40th National Safety Congress, Conrad Hilton, Congress, LaSalle. Morrison and Sheraton Hotels, Chicago. Oct. 24, Fall Meeting of Mining Branch of the Southern California Section, AIME, Statler Hotel, Los Angeles. Oct. 24, Illinois Mining Institute, annual meeting, Hotel Abraham Lincoln. Springfield. Ill.

Jan 1, 1952

By C. E. Murphey

C. E. Murphey, Jr., has presented a relevant, simplified comparison of drill string response when drilling with and without bumper subs. His point that drilling without bumper subs gives conditions further from resonance is valid. Thus, drilling from a floating vessel without bumper subs is undoubtedly feasible, especially when the heave motions of the drilling vessel are small. When these heave motions become large, an evaluation of the magnitude of the change of bit weight is a requirement for a realistic comparison between using and not using bumper subs. As Murphey states, this evaluation should include the effects of damping and presence of drill collars. The analysis would be similar to that presented in our Appendix, but is far beyond the scope of this Reply. ***

By S. H. Williston

IT IS not often that bore hole surveys can be checked by actual civil engineering methods. A recent Arizona survey was checked by normal surveying methods and the comparison of the results should be of value to both oil and mining men. During the summer of 1948 the Phelps-Dodge Corporation, at its Copper Queen property near Bisbee, Ariz., drilled a 1245 ft, 8 in. diam, churn drill-hole in a mineralized area and cased part of it, intending to use it to transfer mill tailings for stope fill. The hole, as frequently occurs, was not straight, and, in endeavoring to locate the bottom in the underground workings, they found no evidence of the hole at the underground coordinates directly below the surface location.

Jan 10, 1950

We regret to advise that, owing to unusual pressure of business at our printers, Volume TAX will not be ready for distribution so early as was announced in the last Bulletin. It will probably be distributed in November. Volumes LVII and LVIII were mailed during the month of August to all members whose dues were paid on Aug. 1; members who failed to receive their Transactions within a reasonable time are requested to notify the Secretary. In the case of members who have recently changed their addresses, the Transactions Were sent-to addresses on record on Aug. 19; those who did not notify .us of change of address until after Aug. 19 will find their Transactions at the old address.

Jan 10, 1918

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) The governing body of the Imperial College of Technology, London, S. W. (Royal School of Mines), will shortly proceed to the appointment of a Professor of Metallurgy. This important Chair has been filled in the past by such eminent metallurgists as John Percy, Sir William C. Roberts-Austen, and others. A large manufacturing company having two iron foundries, blast furnace, etc., requires the services of a chemist, metallographist, and metallurgical engineer qualified to give advice on cast iron practice, and to prescribe remedies for difficulties often met with in the usual iron foundry. The position of converter blower at a side-blow Bessemer steel casting plant is vacant.

Jan 5, 1913

During the nineteen months in which our country was actively engaged in the war, the United States Shipping Board Emergency Fleet Corpn. expanded the shipbuilding capacity of the United States from an unimportant position among the world's producers of ocean-going tonnage to first place. At the same time it increased the overseas merchant fleet of the United States from a negligible quantity to second place. The shipbuilding program has been greatly reduced since the signing of the armistice. There have been suspended or canceled contracts for 754 ships aggregating 3,797,825 deadweight tons, which would have cost $797,564,276 to complete. The cost of canceling these contracts will be about $202,853,456, and the saving effected by cancelations will approximate $594,710,820.

Jan 7, 1919

BUSTS of James Douglas and his friend, Ben Williams, placed in front of the library at Bisbee, Ariz., were unveiled there on April 8, and the connection of the two men with the development of the. Copper Queen mine was reviewed. Judge Bisbee, the brother-in-law of Ben Wil-liams, secured an option on the Copper Queen claim, financed its development and sent Ben Williams in to build the smelter, which turned out its first copper in November, 1880. Dr. Douglas, who was then superintendent of the Chemi-cal Copper Co., at Phoenixville, Pa., had a refining plant and, looking for more metal to refine, came to Bisbee early in 1881, where he negotiated a contract to refine the Copper Queen copper.

Jan 5, 1928

Wanted.-Engineer for copper-leaching plant, designing building and operations. No. 361. Wanted.-Competent, designing-engineer draftsman, experienced in mill design, construction and operation. Also in-cement works engineering, ore-dressing or concentrating plants. Should be able to design and make working drawings of machinery. Salary $3000. No. 362. Assistant Manager.-By large mining and cyanide milling company, located in Northern 'Mexico. Applicant must be mining engineer with executive ability; must speak Spanish; have good practical knowledge of principles of mining and cyanidation silver sulfide ores; must be capable of handling large organization during absence of manager. Only first-class, competent man below middle age need apply. Copies of references and full information covering experience required. State minimum salary expected. No. 363.

Jan 1, 1919

US 4,189,461-Hydrometallurgical extraction of values from a sulfide ore of copper, silver, nickel, cobalt, molybdenum or zinc Ore is leached in a first stage with an aqueous nitric acid leach liquor and In a second stage the preleached mineral is oxidized with nitrogen dioxide to enable the metal values to be solubilized. The second-stage leach liquor is routed to the first stage, while first-stage liquor is subjected to electrolysis or other treatment for values This patent is a continuation- in-part of US Patent No. 4,132,758, dated Jan 2, 1979. R E Lueders and T C Franiewicz, assigned to Kennecott Copper Corp Feb. 19, 1980. 8 pp. (423-27). Filed. 2-23-78 (880,552). (Drawing below)

Jan 1, 1982