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By M. C. Tippett

The modern era of mineral exploration in Panama began in the late 1960's, resulting in porphyry copper discoveries at Petaquilla, Rio Pito, and Cerro Colorado. In contrast, Panama's early mining history (1503 to the early 1700's) was associated with gold. A single mine, Cana, in Darien Province, produced more than one Million ounces of gold in the colonial period. Except for episodic exploration activity by British and French interests, Panama's gold potential since the 1700's has been largely ignored.

Jan 1, 1989

Jan 1, 1931

By William J. Miles

Bentonite Corporation decided to pursue ISO-9002 Registration for our bentonite production for many reasons. We wanted to improve our current Quality System to encompass all business aspects, not just Quality Assurance. We wanted this system to build supplier/customer confidence and provide our customers with all the services that they needed for their business functions: such as Quality Assurance for their needs; appropriate shipping and delivery; appropriate billing; and appropriate sales, technical and management support of our product. These objectives of our Quality System are addressed by the ISO 9000 clauses and requirements. There were additional reasons and expectations for implementing an ISO 9000 Quality System. ISO 9000 registration would develop and aid international sales since the ISO system is a basic requirement in many parts of the world such as Europe and the Far East. It would bring acceptance of bentonite products by new customers and markets Another objective was to develop better trained employees. We hoped that the ISO Quality System would help us reduce costly non-conformances and reduce overall production and operating costs. We hoped to achieve ISO 900 registration before our major customers required it. For example, our major market is use of bentonite as a binder in foundry mold sand systems. The foundries in North America primarily service the automobile manufacturers who have individual Quality System requirements that are being merged with ISO 9000 Standards. As the foundries addressed the automobile manufacturer?s needs, Bentonite Corporation received numerous inquiries and surveys of our Quality System and its conformance with ISO 9000 Standards. Eventually, ISO 9000 Registration will become a requirement to directly or indirectly service this market.

Jan 1, 1996

By Akita Ito, Sumio Kato, Mikio Sugai, Shinichi Nakata

"Spark Plasma Sintering (SPS) is a newly developed method for the sintering of metal and ceramic powders, and completes their densification at low temperature and in short period. The SiC powder was synthesized from diatomite and graphite or carbon black by heating at 1 450°C for 1 hr in an argon atmosphere. The synthesized SiC powder was heated at 1500-1800°C, 50 MPa for 15-18 min by SPS. The relative density of sintered SiC body increased with the rise in the temperature. The oxidation of the surface of the SiC particle and impurities in SiC from diatomite greatly influenced the sintering promotion of SPS.IntroductionThe SiC has high hardness because of the covalent bonding, and is also excellent in thermal and chemical stability. However, it is difficult to obtain a dense SiC sintered body by the combustion heating-method. Therefore, the dense SiC bodies have been made by the use of additives and I or the hot pressing (HP) method.In this study, the SiC powder was synthesized by using diatomite of natural products and graphite, and carbon black of reagent as raw materials, and the relationship between the properties of SiC powders prepared at various synthetic conditions and the density of sintered body by SPS was examined."

Jan 1, 2000

By P. Beauvais

Philip Beauvais, from the Met Office's International Mining and Agriculture Department, explains the need to understand the impact of the weather and climate when developing future mine sites.

Mar 1, 2015

By AIME AIME

THE following is the discussion of a paper, with the same title, by N. L. Alison, which appeared in our February issue: E. F. Tillson commented that while the fundamentals are well presented it would have been of interest to him to have had the author add some of his own experiences with fan installations. A. W. Hesse remarked concerning the use of the forward curved blade fan on the surface at a metal mine which has, ordinarily, but few airways, that the farther they are driven, the higher the resistance rises, and less air will be delivered, as the water gage will remain constant with a consequent loss in quantity. D. Harrington added that the metal mines do not or¬dinarily install fans until the mine is well developed, so changes are relatively slower after fan installation than at a coal mine.

Jan 1, 1930

By AIME AIME

IN accordance with the provisions of Art. XII, See. 3, of the By-laws of the American Institute of Mining and Metallurgical Engineers, the Board of Directors hereby give notice of their intention to amend the By-laws as follows : Art. V, Sec. 2. Amend by substituting the word "senior" for ('first" before the words "Vice-president" in line two of the third paragraph of said section which relates to the calling of special meetings of the Board in the absence or disability of the President.

Jan 1, 1930

By W. B. Plank

THE figures on enrollment in the engineering schools of the United States and Canada indicate that the total number of students in these schools for the current year, 1949-50, is about 10% less than it was a year ago. This year, 226 - 533 undergraduates and graduate students are studying engineering in the United States and Canada as compared with. 249,913 students last year. These figures are taken from advance data in the Journal of Engineering Education for February 1950.

Jan 1, 1950

By Robert B. Sosman

ONE of the most neglected fields for physicochemical education as well as for research is that of high-temperature phenomena. Few universities or technical schools give instruction in the physical chemistry of substances at high temperatures. On the contrary such instruction is almost entirely confined to the region between the freezing and boiling points of water. This field should be extended to a much wider range of temperatures, both low and high. Such an extension is logical, sound, feasible, and practical.

Jan 1, 1943

By Ralph M. Roosevelt

IN AS MUCH as our Institute, by tradition, never adopts any official view of matters upon which difference of opinion exists, it may be taken for granted that the duty of its Production Control Committee does' not embrace the formulation of any general policy on that much-discussed subject. During the first years of its existence the Committee confined its activities to making arrangements for an annual general session at which the broader aspects of the general problem were discussed by men both within and outside the mineral industry. These general sessions, although interesting, did not indicate any definite path of progress, so during the last year the Committee has held a number of luncheon meetings at which the members might discuss in detail problems existing in the specific industries with which they are most closely acquainted, in the hope that discussions dealing with conditions rather than theories might result in the bringing to light of some general truths. Most of these truths have been fairly obvious from the beginning but they are of such basic importance that a periodic restatement of them seems worth while,

Jan 1, 1932

By AIME AIME

MANY producers have held that the only workable quicksilver ore is easily recognized by its .cinnabar content. In most cases this is true. A noticeable exception is a. particular opalite deposit where part of the ore now being mined in considerable quantity shows only the yellow mineral, calomel, or its alteration products. This mineral, on exposure to the sunlight, quickly becomes coated with gray or black layers that may be removed by scraping to reveal the yellow mineral beneath. The blackening of this mercuric chloride on exposure to sunlight shows reaction to form metallic mercury, which is usually plainly present in this class of ore.

Jan 1, 1929

By Chas. Kohl

ABOUT 1929 an engineer was engaged to organize a Safety Department, lay out an educational program, and achieve a reduction in accident frequency. Due to the large number of employees, about 12,000, and the distances between the various properties, it was a big undertaking. Most of the workmen are from the Sierra and for generations have been agricultural people, with little conception of modern tools and machinery, and to a large degree are illiterate. However, gratifying results have been obtained, as evidenced by the accident frequency curve during the sixteen-year period. Safety offices have been established in each of the six major properties, staffed by men who devote their entire efforts to inspections of working conditions and equipment, instructions as to safe methods, and investigations of accidents. The Corporation is a member of the Inter-American Safety Council, receiving their publications and literature, which serve to keep us up to date and informed on modern methods. Dissemination of this material is accomplished chiefly through word-of-mouth and bulletin boards. When it is found that the accident rate is increasing in a certain occupation, as for instance underground haulage or mine hoisting, the operators so engaged are assembled and given renewed instructions on the safety code pertaining to their work. Inter-camp competitions in accident avoidance are being conducted, with annual awards for that unit having the lowest severity rate for the year.

Jan 1, 1945

By PAUL AUDIBERT

THE downward trend of metal prices seems to act something like a reagent that precipitates selfishness in most business men's hearts; in the same way the upward trend precipitates altruism. Operators do not say: "I continue working my mine without curtailment because I can afford the present prices while my neighbor cannot and thus will give me way." They say: "I continue working my mine because 1 consider it a service for consumers. They will get better prices on a free market. Any curtail¬ment would be an attempt to raise prices artificially, that is to say, bad economics." Copper producers have learned how fallacious is such an opinion. It perhaps was not fallacious in olden times when all mines were worked on a small scale even if operating on a big deposit. At that time the supply and demand law played fair. When prices were too low and profits were vanishing for many mines, they would. shut at once, then little by little the metal scarcity would induce prices to climb up again; finally these prices would reach the point when it became profitable to again work the closed mines. Re-opening and shutting down mines was then a normal custom. Workers and operators weakly deplored this unstability, but there was nothing effective they could, do about it.

Jan 1, 1931

By Roger E. Barthelemy

PRIMITIVE mining and metallurgy has today almost disappeared. Probably the only remaining tribal tin mining and smelting is practiced by the Laotian natives in one of the less known tin areas of the world. This district lies almost a thousand miles from the sea along the Mekong River, one of the longest rivers in the world, that marks the border between Siam and Laos, one of the five states forming French Indo-China. Less than twenty years ago it took more than two weeks' travel on elephant-back to reach the spot and today it still takes many days of travel, using all kinds of transportation from automobiles to native

Jan 1, 1938

By H. Foster Bain

AFTER all, mineral sanctions are not a measure of peace, they are a measure of war, and we must regard them as such. We have had two examples now in the world-first, Italy, and secondly, Japan-where we have applied sanctions. When we got ready to apply sanctions to Italy that would hurt, they went to war. In the Far East, when we applied sanctions against Japan, in the latter part of 1941, there was a quick reaction, and the Japanese bombed Pearl Harbor.

Jan 1, 1944

By E. A. Holbrook

LOCAL yearly taxes levied on bituminous coal lands in Pennsylvania have become a cost of first importance to the coal industry of the State. In Pennsylvania there is no State tax on real estate, but local taxation of real estate furnishes the greater part of the revenue necessary for the small governmental unit, as counties, townships, boroughs, and local school, road, and poor districts. Coal in place in the ground, whether or not title thereto has been severed from ownership of the surface, is assessed as real estate and on its supposed sale or market value. There are eight classes of counties in Pennsylvania, based on population; in populous counties of the first, second and third class, assessments are made by a county board appointed by the county commissioners and are fairly uniform throughout the county. In counties of the fourth to the eighth classes inclusive, property assessments are made by property assessors elected by and for each township within a county. In these counties the board of county commissioners acts as a board of equalization and review to hear appeals. In most counties, therefore, where there is a large unmined reserve of coal, assessments on that coal vary for each township, irrespective of the fact that the coal bed is continuous under many townships.

Jan 1, 1933

By AIME AIME

ALL 32 of the Local Sections of the Institute in the continental United States and practically all of the Divisions as well, had representatives present at the Conferences of Local Section and Division Delegates at the Annual Meeting. Three sessions were held, two on Monday and one on Thursday, both the incoming and outgoing Presidents of the Institute being on hand to con- duct the meetings. H. J. Brown was called to the chair during a portion of the last session, President Fulton having to leave early. Complete minutes of the meetings have ,been sent to all delegates. In general, the Local Sections appeared, from their reports, to have risen to the wartime demands made upon them with their usual resourcefulness. Apparently more difficulty has arisen in the last year in arranging attractive programs and securing acceptable speakers, this being perhaps attributable to the fact that most technical men have been extremely busy. Careful planning ahead .has usually brought good results, however. Another wartime difficulty has been the matter of transportation to meetings, gasoline rationing and congestion on the railroads and buses being a handicap to attendance. Sharing cars has proved practical as a method of meeting this issue, this again requiring planning. Suitable meeting places and a supply of food have been another difficulty for some local groups.

Jan 1, 1944

By John T. Ryan

FOR the first ten months of 1942, on which data are available at the time this is written, the coal-mining industry achieved a most creditable safety record, and ha1 figures for the year may show a record surpassing that of 1941 in which the industry reached the best accident rate in its history. The ten- month accident rate for both bituminous and anthracite mining in 1942 was 2.197 fatalities per million tons of coal mined, compared with a revised rate of 2.271 for the same months of 1941. The bituminous rate decreased from 2.139 in 1941 to 2.039 for ten months of this year, and the anthracite rate shows a reduction from 3.707 to 3.699 for the same period.

Jan 1, 1943

By T. Palangio

Most blasters wouldn’t think of initiating a shot without a seismograph to record vibration and air blast results. Some might even measure the velocity of detonation but few surprisingly record the event on video, photo document loading conditions or take pictures before and after the shot. This paper discusses digital imaging, the equipment, methods, techniques and information that can be learned from digital pictures taken in the field during blasting operations. The guy who said “a picture is worth a thousand words” probably understated it.

Jan 1, 2008

By Cláudio S. S. Pinto

Em face do agravamento da situação da energia elétrica no Brasil, com disponibilidade cada vez mais restrita e custo cada vez maior, torna-se urgente reduzir o seu consumo onde possível. Ventiladores centrífugos de processo de médio e grande porte são grandes consumidores de energia elétrica e podem ter um elevado potencial para a redução do seu consumo. Este texto mostra como identificar a possibilidade de economizar o uso da energia elétrica em um determinado ventilador e que modificações ele necessita para cumprir este objetivo.

Sep 25, 2017