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By W. A. Nordland

BISMUTH can be readily grown into single-crystal form using the so-called "quick freeze" growth method.' Some advantages of this method are that very large crystals can be grown in a relatively short time, and with comparatively simple apparatus. We have found the general quality of crystals grown by this method to be not as good as that of "pulled" crystals.' This communication describes a "quick-freeze"

Jan 1, 1968

By Kenneth C. Stewart

Eight brands (three samples of each kind) of commercially available audio-dosimeters were performance-tested. Each unit was placed in an anechoic chamber and subjected to various acoustic signals to measure its A-weighting response and overall integration accuracy. All units met the A-weighting tolerance for type II sould level meters, and six brands were within the Bureau I s overall accuracy requirements of ±2 dbA referred to input.

Jan 1, 1974

By Joan T. May

Anhydrous methods were tested for the extraction of beryllium from low-grade source materials. The purpose of the investigations was to find new extraction processes that are applicable to domestic ores. Beryl, helvite, and phenacite materials containing from 0.1 to 2.8 percent BeO were used as starting materials for direct halogenation tests and pretreatment followed by halogenation. The results of the investigations showed that direct fluorination and carbide-chlorination are two practicable methods that can be applied to low-grade concentrates. Treatment of concentrate-carbon mixtures with anhydrous hydrogen fluoride extracted 99 percent of the beryllium in the concentrate; the soluble fluoride product, converted to an oxide, contained 70 percent BeO. Chlorination of beryllium-silicon carbide, prepared from low-grade concentrates, extracted beryllium into the volatile chloride product.

Jan 1, 1962

By G. D. Ritson

Gold surveys were sent to 21 gold operations around the world. Eleven different surveys were sent, each targeting a dif­ferent unit operation used commonly in gold processing. On a monthly basis the individual reports were returned to the opera­tions. Empirical data collected during the surveys has con­tributed to more effective engineering design. Graphical rela­tionships established have been used by the operations to "benchmark" performance against the industry and identify areas of possible improvement. This paper presents some of the findings related to the fol­lowing four surveys that investigated parameters specifically relating to carbon processing. Rescan Gold Survey GO 1 - Carbon Management practices Rescan Gold Survey 003 - Carbon Stripping Rescan Gold Survey 006 - Carbon Loading Isotherms Rescan Gold Survey 007 - Screening A final report documenting all the surveys will be compiled

Jan 1, 1998

By Alden Greninger

MANY recent contributions in the field of theoretical metallography have been concerned with crystallographic definitions or descriptions of various phenomena. The lattice orientation of the crystal being studied must be known before such definitions can be made. Practically all the metallic crystals used do not have crystal faces-other than the unknown "plane of polish"; hence resort must be had to other means of determin-ing orientations. Some use has been made of etch-figures, slip bands, optical properties, etc., for this purpose; but for. accurate results, and because of the fewer restrictions to their use, the various X-ray methods have been the most satisfactory.1 The methods that, have been used may be divided into two general classes: (1) oscillation methods, and (2) transmission Laue methods-2

Jan 1, 1934

The National Mining Hall of Fame and Museum will hold its Ninth Annual Induction Banquet Sept. 8, 1996, at the Las Vegas Hilton Hotel. Six mining greats, two of them living, will be enshrined at the event. They will join 126 other mining legends previously honored by the hall of fame. The keynote speaker will be William Perry Pendley, president and chief legal officer of Mountain States Legal Foundation in Denver, CO. Jeffrey Zelms, president and chief executive officer of The Doe Run Co., will be master of ceremonies. Richard Swayne, regional director USA for Boart Longyear Co. of Salt Lake City, UT, will introduce the speakers. Thomas Falkie, president of Berwind Natural Resources Corp. and chairman of the Mining Hall of Fame’s board of governors, will enshrine the inductees.

Jan 1, 1996

By Yves Caron

Résumédes travaux effectués De septembre 2009 àmai 2011 ? Plus de 21 000 m de forages complétés en avril 2011 et près de 9 000 échantillons ? 2,7 km de décapage, 52 tranchées et 852 m de rainures ? Estiméde ressources 28 mai 2010 (SGS Géostat) ? Essais métallurgiques en laboratoire (automne 2010) ? Étude économique préliminaire (janvier 2011)

May 1, 2011

By H. Xi-Lum

Three rapid cold bonding production methods wing sponge iron powder as a binder for low temperature pellets have been successfully developed. These methods differ from ordinary bonding by the elimination of salt and other catalyzers, equipment corrosion and environmental pollution. Experiments show that these pellets have good metallurgical properties. A semi-industrial test has proven the laboratory results, with the continuous and stable production of metallic pellets. These methods replace traditional high temperature firing of oxidized pellets for direct reduction. As a result, the plant for oxidized pellets can be saved and substituted for grate in the grate-kiln system. Thus, 20% of the investment could be saved, and production cost may also be decreased because the production of cold bonding pellets does not need additional space.

Jan 1, 1984

By George C. Toland, Ronald E. Versaw

Most existing impoundment ponds and dams leak effluent into the soil or rock upon which they are constructed. However, proposed environmental legislation will require very stringent control of the release of toxic effluents such as cyanide. More exacting investigation, design, and construction techniques than have been used in the past will be required to satisfy these new regulations. The types of field and laboratory investigations required to develop the data for the design of an impoundment system containing toxic effluent are discussed, together with the technical considerations necessary to design this system. Design topics include reservoir sealing with natural and man-made materials; embankment sealing; embankment design considering stability, surface hydrology, capacity, and downstream catchment basins; and special implications of cyanide effluents.

Jan 1, 1977

By Tony van der Steen

Subsea mining system are designed for the following, principally different, tasks: Dreding - The destruction and removal of seabed sediments overlaying the bedrock. Cleaning - The competence of the system to systematically remove the deposits from an undulating hard bedrock with irregular pulleys, channels and fissures. Factors that influence the choice of dredging equipment for a specific project are project requirements such as environmental conditions, location and water depth. However, the most important selection criteria are soil conditions. As a consequence, possible dredging systems, must be evaluated for the following, principally different, characteristics: Dredging proficiency - The destruction of the strata by the equipment. System stability - The capability of the soil to support the subsea equipment The above parameters are determined by the strength characteristics and the bearing capacitv_ of the soil. The author describes the processes involved in excavating the subsea deposits and (transporting the gathered soil as a water-soil mixture to the surface using different excavation and transport methods.

Jan 1, 1998

By Steven Doyle

Presentation Outline ?Introduction to Brunswick Mine ?Mining Needs and Drilling Trends ?Maintenance Program ?Back to Basics ?Results ?Additional benefits Introduction Xstrata Zinc Brunswick Mine ?No. 12 deposit discovered in 1953, pilot mining 1957, u/g mining began in 1964 ?Zinc, copper, lead and bulk lead/zinc concentrates ?Since 2007, a fully owned division of Xstrata Zinc Canada ?Over 132Mt milled 3.4 % Pb, 8.8 % Zn and 102 g/t Ag ?Deposit dips approximately 70 degrees; strike length of 1200 m; currently mining from 250 m to 1125 m depth

Nov 1, 2011

By Terry M. Hertel

Zortman Mining has spent approximately three years evaluating the metallurgy of the sulfide ores from the mining area of the possible expansion project. As the test program proceeded, an interesting series of events took place which changed the scope of the work. During the agglomeration work, one of the control columns was inadvertently set up without the addition of lime to the material prior to loading and subsequent leaching. The gold recovery from this column was comparable to those columns that had a lime addition of 10 pounds per ton of ore. In fact, the gold recovery curve had a much steeper slope than those of the other columns. Furthermore, the pH of the pregnant liquor from the "no lime" column recovered to typical levels as fast as the solutions from the "lime" columns. These observations led to the concept that rinsing the ore with water prior to cyanide leaching could be advantageous to the heap-leach process.

Jan 1, 1992

By Tucker A. J

An overburden blast utilising horizontal blast holes was successfully attempted at the Ulan Coal Mines during December 1991. The blast reduced operational problems and costs and improved dragline productivity in an area of that contains poorly consolidated sands and clays overlying very hard Permian strata.The fan shaped shot consisted of seven 250 mm diameter holes between 80 and 95 metres long drilled into the highwall face. The holes were loaded with ICI Powergel Gold 25606 bulk Emulsion explosive. The design powder factor was 0.15 kg/bcm for the total shot of 180 000 bcros and 0.44 kg/bcm for the competent Permian strata into which the holes were drilled. Fragmentation from the horizontal blast was comparable to areas conventual blasted. Following the success of this shot further shots are planned for this area.

Jan 1, 1992

Plenary SpeechI have given considerable thought about what I might say to such a group of professionals, given that I am not an extractive metallurgist. It was immediately apparent that I would quickly be out of my depth if I tried to present some technical aspect of extractive metallurgy. So, instead I thought it might be useful to review the subject from the minerals business management point of view in order to improve understanding for the extractive metallurgist who some times finds it difficult to comprehend directions being given by management.

Jan 1, 1992

By K. J. Stanaway

Environmental pressures on waste disposal are forcing pigment producers to use feedstocks with higher Ti02 content and lower levels of trace elements. Despite this, 50% of the world's Ti02 comes from ilmenite concentrates with only 37% to 54% Ti02. An industry growth rate of 25% in the next 10 years, combined with trends to diminishing resources and lower mining grades for rutile (95% P02) and leucoxenized ilmenite (55% to 90% P02), means that unless new discoveries are made soon, the industry will become even more reliant on ilmenite.

Jan 1, 1995

By J. Steven Whisler

Corporate managers are facing increasingly demanding challenges as they seek to ensure compliance with environmental laws. Management also must deal with new liabilities created by environmental laws. These laws provide both private groups and governmental agencies with access to the courts to seek penalties, compliance orders, cleanups, or to forestall developments that could affect ecosystems. Environmental laws and liabilities are also affecting commercial transactions, including the availability of financing. Corporate managers must develop new and innovative methods to address these challenges in order to assure both sustainable industrial growth and stewardship of the environment.

Jan 1, 1991

By Sheldon Shepherd

Fifty years ago, belt scales were mechanical devices based on a complex weight balancing design. Today's systems use load cells to assess material weight, belt speed sensors and microprocessor-based integrators to continuously compute the rate of material transferred along a conveyor. Belt scales have become important assets to a plant. They help maximize the use of raw materials, control inventories and aid in the manufacture of a consistent product. Choosing and installing a belt scale system may seem complicated but it can be simplified by following a few guidelines.

Jan 1, 1999

By David G. Chedgy, Edward A. Zawadzki, Robert D. Stoessner

Extensive research and testing in commercial facilities has clearly demonstrated that heavy medium cyclones are the most effective process for cleaning a 0.6 x 0.15mm (28 x 100 Mesh) coal at low separating gravities, less than 1.35. This paper describes testing performed to deter- mine system characteristics at these lower gravities and the type of circuitry required to maximize performance. The results of these studies include both pilot and commercial scale tests of cleaning 0.6 x 015mm (28 x100M) coal.

Jan 1, 1988

Mining software systems have provided a basis for integration of resource, survey, and design functions. They can similarly provide a basis for incorporating ground conditions into the process.Exploration and mine geologists have a prime role to play in this process, extending their responsibilities further across the geological spectrum, into exploration of ground conditions, analyses of results, and assessments of their implications for mining. Ground conditions are as much a part of the geology of a prospect or mine as its mineralisation, and can have critical imnlicationa for mining.

Jan 1, 1993

By Kurt O'Bryan, Gary Beerkircher

WaterFlush Technology offers maximum comminution performance benefits over to­day's more common comminution methods. These benefits will be presented with case studies of existing installations, and the projected performance gains for circuits scheduled to begin operation in 1992.

Jan 1, 1992