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By AIME AIME

FEW mining schools possess an art gallery and certainly none can equal the collection of paintings depicting the mineral industries now hanging in the comparatively new building of the School of Mineral Industries at The Pennsylvania State College. Dean Steidle, who conceived the idea, early this spring boasted of 55 paintings in the collection, by 24 different artists, the gallery being appraised at $18,000. Since then, eleven additional paintings have been added. Opportunity will he presented for an inspection at the meeting of the Industrial Minerals Division, to be held at the College, Sept. 24-26.

Jan 1, 1936

Commodities statistics and other information are available through the following three systems: Internet Access: To acccess the USBM Gopher server on Internet, connect to: gopher.usbm.gov port 70, using gopher client software. Or contact the Systems Administrator for technical questions: Matt Klevemann, 412-892-6499 (klevemmc@miner.usbm.gov) These USBM materials are available on Internet, with more to come in the future: Publications and other research findings, including this bimonthly publications list, newsletters, tech transfer updates, enviromental technology research, health and safety information. USBM software products Media materials and speeches. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219-3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button on your fax machine.

Jan 1, 1995

By C. H. Bucknam

Principles of Green Chemistry provide useful guidance for sustainable mineral process development. Laboratory bench scale testing was carried out using pregnant cyanide leach solutions, and a number of commercially available mercury precipitation reagents were compared using jar testing to determine the most efficient and selective reagents for mercury precipitation. The most efficient reagent identified was sodium polymeric thiocarbonate (NaPTC).Coagulation experiments with fine diatomaceous earth resulted in a stable precipitate, with good settling properties. On line monitoring of the mercury in solution is recommended for process implementation to conserve reagent removing approximately 90-95% of the mercury with minimal silver and negligible gold losses.

Jan 1, 2004

Jan 1, 1967

By B. Cavender

Safety departments have traditionally been held responsible for the safety performance of their division or company. This approach leads to a lack of ownership of safety issues by the larger organization. An alternative paradigm is significantly more effective: the members of the work force (managers as well as workers) are fully responsible and accountable for safe production. The safety department is not extinct, however. Its role has changed, to focus on training, litigation, and external relationships such as community relations. This approach was implemented at BHP Copper's Superior mine and mill in Arizona. By obtaining the genuine commitment of the work force to accident-free production, the mill's MSHA incident rate immediately dropped from 7.4 to zero. The mill also ran one year with no MSHA citations. When this philosophy was implemented at the divisional level, the division's incident rate decreased from 9.5 to 1.1,an 88-percent reduction in six months.

Jan 1, 2000

Ion exchange (IX) has been in use for a long time, references to IX are made in The Bible, Exodus Chapter 15 vs. 22-25 ?and the waters were made sweet?.1, 2 Aristotle noted a reduction in the salt content of water when passed through certain types of sand, a phenomena probably associated with ion exchange characteristics of zeolites. Some major milestones in IX development include; ? ~ 1400 BC Moses ? ~ 330 BC Aristotle ? 1850 the discovery of the IX process3 ? 1909 Gans proposed zeolites for gold recovery ? 1935 sulfonated coals used for water softening ? 1939 copper recovery from Rayon Production ? 1940 The Rare Earth Project at Ames ? 1952 first South African U IX mine at West Rand (first SX of U using amines 1957) ? 1954 first U IX in USA at Shiprock Mine N.M. USA. ? Late 1950?s U IX over 50 fixed bed systems installed in North America ? 1950?s-1960?s FSU introduce U IX both fixed bed and RIP ? 1968 Gold IX (RIP) Muruntau Uzbekistan (CIL wasn?t commercialized until 1973) ? Mid 1970?s FSU & USA independently develop ISL combined with IX for U recovery ? 1978 Chinese Tungsten IX commercial Plant ? 1984 Uranium extraction from seawater ? 2004 Recovery of Gallium using hydroxyamic acid ligands ? Current ? Commercialization of IX for recovery of gold thiosulfate. Ion exchangers can be naturally occurring or synthetic; the majority of ion exchange materials in use today are synthetic resins based upon organic polymers such as polystyrene or methacrylate. Into more modern times the use of ion exchange for metal recovery was first proposed for the recovery of gold using zeolites in 1909.4 In 1939 copper was being recovered from the manufacturing of Rayon using ion exchange5 a development that continued applicability through to current times in the production/recovery of copper and nickel in ammoniacal leach processes. In early 1949 researchers at the Rohm & Haas Company discovered that hexavalent uranium existed as an ionic complex in sulfuric acid leach liquors, and that quaternary ammonium anion exchange resins exhibited a high selectivity for this ionic species6 The first commercial application of this technology went on-stream in October 1952 at the West Rand Consolidated Mines, Ltd operation in South Africa. 7 Ion Exchange has been applied for the recovery and purification of a range of metals;8 ? Uranium, Thorium and transuranic elements ? Rare Earths ? Gold, Silver and platinum group metals (PGM?s) ? Chromium, Copper, Zinc, Nickel, Cobalt ? Refractory Metals; Molybdate, Vanadate, Tungstate, Rhenium Mercury.

Feb 27, 2013

By Wang Xuguang, Tian Ruigi, Xiong Shangbin, Xiong Daiyu

Combining action features of explosive shock with those of natural lignocellulosic biomass structure, we have successfully developed a new explosive shock dilatation and separation technique for pretreatment of natural lignocellulosic materials in the laboratory. Based on a brief introduction to the technical background and experimental procedure of this new method, some preliminary experimental results are given and discussed: the scanning electron microscope (SEM) qualitative observation results show that for treated natural lignocellulosic sample such as corn cob etc., their length of fibre bundle shortens, fibre bundle arrange disorders, biomass appearance and structure of samples largely change to be dilatation and loose state. The dilute acid hydrolysis quantitative measure results show that for treated samples, the overall yield of the reducing sugar largely increases, hydrolysis rate of corn cob sample is over 80%, rate and speed of hydrolysis are increased by times.

Jan 1, 1998

By Walter Harvey Weed

The Republic of Mexico is traversed by many mountain ranges, and presents a great diversity of climates, soils and geographical features, yet its grander geographic provinces are few and peculiarly well defined. The Gulf plain, the Cen tral plateau, the Sierra Madre, and the lowland or Tierra Cali ente of the western coast are the main features of the geogra phy of the Republic, and in the northern half these provinces are particularly well defined. The Sierra Madre separates the Republic into eastern and western parts, and from the City of Mexico north to the Texas line presents an almost impassable barrier to east and west travel. On the north, the first wagon road pass from east to west is at El Paso del Norte, the site of the Texan city of El Paso. Southward for many hundreds of miles the Sierra Madre, traversed by well-worn trails, over which all travel from the west coast to the interior must pass, is a stupendous barrier to social and commercial intercourse. The Sierra Madre is commonly described as a range or con geries of mountain ranges. In fact, it is, in Chihuahua at least, a great plateau, fringed by mountains on the east, trenched by deep canons in its center, and bordered by a wild and rugged complex of mountains carved out of the plateau on the west. Professional duties took me across this region from Parral westward to the Gulf of California via Guadalupe y Calvo. As it includes some of the great ore-deposits of Mexico, and its geological features have never, so far as I am aware, been described, I have prepared a diagrammatic section made from my observations on a horseback trip across the Sierra, and added such notes as seem to be of general interest.

Jan 1, 1902

In 1991, Placer Dome Venezuela established a 70% stake in Minera Las Cristinas, to mine the Las Cristinas gold deposits in Bolivar. This case study examines the multi-sectoral partnership arrangement that was developed to improve health services near the proposed Las Cristinas gold mine. The investment climate in Venezuela is uncertain and the socio-economic circumstances are potentially hostile. Despite that, the partnership between the mining company, local communities, government agencies and an international health nongovernmental organization (NGO) collectively leveraged nearly $2.5 million to build and operate a community health center.

Jan 1, 2002

By John E. Shively, Tracy K. Lundin, Francis Fong

The Superconducting Super Collider (SSC) features two 20 TeV counter rotating proton beams which will be housed in 87 km (54 miles) of tunnel. Four additional lower energy particle accelerators will be housed in 26 km (16 miles) of tunnel and underground structures. Physics experiments will be conducted in two underground detector halls approximately 67 m (220 feet) deep with footprints measuring about 30 m (100 feet) by 100 m (330 feet). Definition and design of underground facilities is advanced with construction of approximately one-third of the SSC program underway. This paper presents an overview and status of the SSC project.

Jan 1, 1993

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4/ issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and, if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous .sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1958

By Howard M. Wells

Portfolio theory and the Capital Asset Pricing Model (Modigliani and Pogue, 1974) provides an investment decision rationale which takes account of the benefits of diversification in reducing effective risk, but this theory does not consider the financial capability of the firm to survive large losses if they should occur. The LL-curve theory (Wells, 1976) takes the latter consideration into account, but it does not provide for the effects of diversification. This paper pro- poses a general theory to account for both diversification and the financial capacity of the firm to underwrite the investment risks.

Jan 1, 1983

By A. E. Dabbagh

Saudi Arabia’s mineral potential offers development target that compliment the national effort to diversify the income of this oil and gas economic based nation. Ma’aden, a joint stock company with paid-up capital of US$1 billion, has from its inception in 1997, actively developed in-house engineering and management skills to transform the Arabian shield’s mineral potential into such real projects. Gold mine operating facilities of 100,000 oz/yr underground and 50,000 oz/yr open pit are de-scribed, as well as 3 targets, two of which are underdevelopment; Al Hajar (3,000 tpd at 2.5 gpt Au)and Al Amar (5,000 tpd at 20 gpt Au). Emphasis is also on exploitation of phosphate rock and down-stream fertilizer products, based on the Kingdom’s107,000 sq. km. northern basin geological reserve. Al Jalamid, the prime target, represents 216 million tonnes of these P2O5 reserves. Saudis and expatriates, together, lead international engineering companies and contractors operating and developing these facilities.

Jan 1, 2000

The International Symposium-cum-Workshop on Management andControl of High Gas Emissions and Outbursts in Underground CoalMines was held in Wollongong in March 1995. Coverage of high gasemissions was virtually confined to instantaneous outburst implications, essentially seam gas pre-drainage. Globally, instantaneous outbursts have been known for 150 years, andthe first Australian outburst occurred in 1895 and Australian occurrences and mines affected have increased since. Few significant coal producing countries are unaffected. The coals affected range in rank from lignites to anthracites. Geological disturbances are the most likely environments for occurrences. The most likely mining geometry is of virgin headings, with some occurrences on longwalls and in other situations. Widespread research into many aspects of the problem has yet to produce a generally accepted explanation. Explosive inducement is a well-known control. Apparently high advance rates increase face gassiness and create higher stress abutments, increasing proneness. The most popular preventive measure, pre-drainage of virgin coal ahead of faces has produced highly successful very long hole drilling performances but without the precision necessary for accurate geometric hole patterns, despite quite sophisticated drilling equipment and hole surveying instruments. For the future, more precise degasification is sought, even from the surface, together with rapid face coal gassiness assessments to confirm lowering below threshold values, as well as other proneness lowering measures, perhaps related to new heading and longwall geometries and to new equipment to provide them. But above all, safe management plans are required for each operation, to safeguard the miners and their working environments, and thus to protect underground coal mining from this mounting threatening problem.

Jan 1, 1997

By David Arana

The use of gas-water dispersion of a molten material flow onto a vibrating surface is developed as a process to minimize water pumping requirements, minimize the risks of explosions, and minimize the post solidification dewatering and fines handling equipment requirements. The process uses existing vibration transport technologies and common plant utilities. Plant trials using the smaller footprint and the progressive molten particle cooling time have yielded encouraging results. The results are analyzed and reported.

Jan 1, 2006

By John J. Sammarco

Abstract- Emergency shutdown systems (ESDs) for mining machinery provide critical functions to safeguard miners. Traditionally, ESDs were realized with simple hardwired circuits; today, there is a growing trend to use programmable electronic technology such as programmable logic controllers (PLCs). This paper describes an analytical study to quantify the safety integrity of a PLC-based ESD and a hardwired ESD. The safety integrity level of each design approach was determined by quantifying the average probability of failure on demand (PFDavg) as described by the recommendations for programmable electronic mining systems published by NIOSH and the IEC 61508 international standard. The safety analyses addressed system architecture, hardware failure probability, proof test interval, diagnostic coverage, and human error probability. The results indicated that a same level of safety, safety integrity level 3 (SIL 3), could be attained when evaluating random hardware failures. Neither approach could attain SIL 3 if manual activation was used. Human error was the limiting factor where, using human reliability analysis, PFDavg < 1 x 10-1; thus, the ESD does not meet SIL 1. It is apparent that automatic verses human¬activation of the ESD is a very important safety consideration. Manually actuated ESDs can only achieve SIL 1 regardless of the technology; therefore, additional independent safety layers of protection are needed to exceed SIL 1. Secondly, it is apparent that the technology choice is very important. The PLC-based ESD was much simpler to design and to validate safety1.

Jan 1, 2007

By X. Zhu, R. Du Plessis, J. D. Miller, D. G. Kotylar

Research on the low-potential hydrophobic state of pyrite with potassium amyl xanthate (PAX) as collector, is reported to help explain and understand the fundamental aspects of the N2TEC flotation process, which was originally developed for the improved recovery of gold from refractory auriferous sulfide ores. Typically in the N2TEC process, air is replaced by nitrogen as the flotation gas, and potassium amyl xanthate is used as collector for the reactive auriferous pyrite particles. The first N2TEC flotation process was commissioned at Lone Tree in Nevada in March 1997 and has been in operation ever since. On the basis of electrochemically controlled contact angle measurements, the low-potential, low-pH hydrophobic state of pyrite has been examined as a function of flotation variables such as pH, gas-phase composition, collector concentration and pyrite potential.

Jan 1, 2000

By Youjun Tao

Falcon centrifugal gravity separation tests were conducted to study desulfurization and de-ashing performance with different size fractions of a high-sulfur Chinese -0.5mm fine coal in a dense medium. Performance indicators such as combustible recovery, ash and sulfur rejection, and desulfurization efficiency were used to evaluate the separation efficiency. The results show that for -0.5 mm coal particles, all performance indicators except ash rejection are higher for the Falcon concentrator than for flotation. More specifically, for the +0.125 mm size fraction, Falcon centrifugal separation produced better ash and sulfur rejection performance than froth flotation. However, the Falcon concentrator also showed higher combustible recovery but lower ash and sulfur rejection than froth flotation for the -0.125 mm size fraction.

Aug 1, 2013

By F. B. Henderson

1.0 PROLOG Since the "end" of the Cold War, revolutionary new research and commercial remote sensing capabilities are being developed that will dramatically change the way we map the earth and address its environmental problems. The technology challenge is not the growth of new environmental remote sensing technologies themselves. It is, rather, how these new innovative observing systems can be accepted and used to the benefit of both the regulatory and the mining communities in the light of present concerns about unknown risks of discovery and liability. The basis for this paper is an unpublished technology primer prepared for the industry-government Workshop on Advanced Measurement and Site Characterization for Mining Impacts held at Colorado School of Mines, Golden, Colorado, July 14-17, 1997

Jan 1, 1999

By Reynold N. Hoover

The bombing of the Murrah Federal Building in Oklahoma City, Oklahoma, on April 19, 1995, has once again renewed public debate surrounding the availability and use of explosives in the United States. In the past, Congressional review of explosives regulation has generally followed tragic events such as the bombing of Pan American World Airways Flight 103 over Lockerbie, Scotland on December 21, 1988; the February 26, 1993, bombing of the World Trade Center in New York City; and the delivery of six package bombs to members of one family in several western New York communities, killing five people, on December 23, 1993.

Jan 1, 1996