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By George D. Brunton

The past and present argillaceous rock studies for the U.S. National Waste Terminal Storage Program consist of: (1) evaluation of the geological characteristics of several wide- spread argillaceous formations in the United States; (2) laboratory studies of the physical and chemical properties of selected argillaceous rock samples; and (3) two full-scale in situ surface heater experiments that simulate the emplacement of heat-generating radioactive waste in argillaceous rock.

Jan 1, 1981

By P. Zhang, W. D. Xiao

"A process mineralogy study was conducted to guide the development of a process for the extraction of vanadic oxide (V2O5) and aluminum compounds from bone coal and its ash as well as the production of byproducts. Results show that to extract the targeted metals at higher recovery rates, one must find a suitable agent capable of destroying the structure of the mica and breaking down the lattices in which these metal-bearing minerals occur. For such minerals, metal extraction efficiency is usually low if the approach is simply adding an oxidant that cannot destroy the structure. In this research, a byproduct fluosilicic acid (H2SiF6) at 20 percent concentration from an operating phosphate fertilizer plant was found to be powerful and effective for the leaching of vanadium-bearing minerals such as mica. This environmentally friendly process improved the leachability of valuable constituents in the bone coal significantly, with the leaching rate of V2O5 increased to 94 percent, from 83 percent, and that of aluminum oxide (Al2O3) increased to 75 percent, from 40 percent. X-ray diffraction and chemical analyses showed that the structure of mica can be destroyed using fluosilicic acid either alone or in combination with sulfuric acid. Based on the process mineralogy study, a processing flowsheet was tested, which resulted in a final V2O5 powder product with purity of 99.2 percent and an overall recovery rate of higher than 85 percent. The flowsheet consists of leaching, ion exchange and ammonium precipitation. With this process, various byproducts could also be generated, including aluminum fluoride, cryolite, aluminum sulfate, calcium sulfate, ammonium chloride, sodium chloride and cement admixtures.IntroductionVanadium is an important rare metal broadly used in the production of steel alloys and nonferrous alloys as well as in the chemical field as a catalyst. Vanadium-bearing bone coal and clays are abundant in China, and they contain other valuable metals such as aluminum. Bone coal is a type of carbonaceous shale. The vanadium-bearing minerals mainly exist in mica, kaolin, iron oxides, tourmaline and garnet. According to previous studies (Xiao, 2007; Xu, 1989; Xu and Chen, 1991; Ji and Xu, 1991; Chen and Xu, 1992; Xu and Heng, 1992), vanadium occurs from the isomorphous substitution of V3+ for Al3+ or Fe3 + in the crystal lattices of mica, tourmaline, garnet, dolomite and aluminosilicate minerals. In iron oxide and kaolin minerals, vanadium appears as an adsorption form. The isomorphous substitution of vanadium is more stable in tourmaline, garnet and silicate minerals. Therefore, vanadium in bone coal may exist in three phases: vanadium-containing kaolin and oxides, vanadium-containing mica, and tourmaline and garnet (Xu and Chen, 1993; Xu and Zhang, 1993; Xu and Wang, 1994; Feng, et al., 2005; Lin and Fan, 2001)."

Jan 1, 2015

By R. W. Macqueen

Organic matter commonly associated with Mississippi Valley-type (MVT) lead-zinc deposits may be used to assess the burial/thermal history of host rocks and sulfides. Organic matter may also have been involved in the genesis of H2S required to precipitate sulfide ores. Pine Point, Northwest Territories, Canada, provides an example. Located on the south shore of Great Slave Lake, Pine Point is an operating world class deposit which has produced 58 million tons of ore containing 3.0 percent Pb and 6.1 percent Zn from more than 40 Individual orebodies. Well-documented paleokarst features in a Middle Devonian carbonate complex are the main ore hosts. Sphalerite and galena ores are mainly open space fillings, and, from fluid inclusion studies, were deposited from saline fluids at temperatures of up to at least 100°C. Forms of organic matter occurring in the Pine Point barrier-reef complex Include indigenous organic matter, heavy oil and bitumen. Based on numerous geochemical criteria, it is clear that heavy oils and bitumens were derived locally from indigenous organic matter. The geochemical character of the Indigenous organic matter demonstrates that the barrier-reef complex is immature to marginally mature with respect to petroleum generation, and has not been heated above about 60°C maximum. Thus sphalerite with fluid inclusions that yield temperatures up to about 100°C represents former thermal anomalies. Bitumen is of two main forms at Pine Point: widespread soft, tarry material soluble in organic solvents (unaltered bitumen); and hard, brittle, glassy material that is mostly solvent-insoluble, and associated with white sparry dolomite and lead-zinc ores (altered bitumen). There are also partly altered bitumens. Unaltered bitumens have atomic H/C ratios of about 1.4, sulfur contents averaging 7.8 percent, and sulfur isotope ratios 634S) of approximately +4.6 per mil. Altered bitumens have atomic H/C ratios averaging 1.02, sulfur contents averaging 22 percent, and 634S values of about +12.9 per mil. These data and the organic geochemical character of a large suite of bitumen samples analyzed, strongly support the concept that some bitumen has been involved in the thermochemical reduction of sulfate to produce the H2S required to precipitate the ores. Mass-balance calculations indicate that the amount and degree of alteration of bitumen is more than enough to account for the reduced sulfur species deposited as metallic sulfides at Pine Point. MVT deposits, including Pine Point, seem to require the coincidence of available metallic Ions, pre-existing pore space, and a precipitating agent. A close look at organic matter in more MVT settings may outline trends in distribution or alteration which can be used as indicators of past thermal environments and processes of ore deposition.

Jan 1, 2013

By A. D. Hammond

"INTRODUCTION The recent drop in iron ore prices has claimed an unwitting casualty in vanadium. Vanadium is dominantly produced as a co-product of steel production. The recent shutdown at EVRAZ’s Mapochs steel-vanadium operations in South Africa has cut-off 10% of the world’s vanadium output. Earlier in February, 2015, Australia’s Atlantic Ltd. suspended operations at its Windimurra iron-vanadium complex after a fire caused severe damage at the plant. Since then, challenging market conditions has resulted in the permanent closure of this operation. This decoupling of vanadium production from integrated iron ore producers presents an opportunity for vanadium exploration companies to target single-product deposits. This trend is manifested in the increasing number of pure-play vanadium ventures around the world.The mine production of vanadium is dominated by three countries namely, China, South Africa and Russia, which collectively produce 98% of the world’s vanadium. While the use of vanadium as an alloy in the steel industry remains by far the largest application for this metal, growth in demand is expected to come from the renewable energy industry in the form of batteries for energy storage. This paper summarizes the current state of vanadium exploration, briefly describes the vanadium market and lists sources of future demand for the metal. TREND IN VANADIUM EXPLORATION The most active participants in the current vanadium exploration are pure-play vanadium ventures in Brazil, South Africa and Australia. These ventures are targeting deposits with higher vanadium grade than those typically mined in titaniferous magnetite operated by integrated steel-vanadium producers. The 10% shortfall in vanadium production resulting from the shutdown at EVRAZ’s Mapochs is expected to be partially compensated by Largo Resources’ Maracás Menchen vanadium operation located in the State of Bahia in Brazil, which commenced operation in August 2014 and is expected to reach design capacity of 11,400 tonnes of vanadium pentaoxide (V2O5) by the end of 2015. The estimated production1 for 2015 is 6,500 tonnes of V2O5 at a target production cost of $3.60/lb. This is the first vanadium operation to be placed in production in the Western Hemisphere in over 35 years."

Jan 1, 2016

By S. G. Ozkan

Boron minerals of economic importance are primarily colemanite, tincal, and ulexite. Turkey and the United States are the leading producers of boron minerals and compounds. Other production includes datolite in Russia and synthetic colemanite in Chile. This paper will discuss various types of chemical and physical treatments of boron ores to produce the marketable minerals and compounds that are consumed in commercial products.

Jan 1, 1995

By Leslie F. Ruppert

The US Geological Survey (USGS) is currently conducting a coal resource assessment of the coalbeds and zones that are projected to provide the bulk of the nation’s resources for the next few decades. The Pittsburgh and Upper Freeport coals are the first two beds in the northern and central Appalachian basin region to undergo fully digital coal assessments. The bed-specific assessments are being carried out in partnership with the state geologic surveys of West Virginia, Ohio, Pennsylvania and Maryland. Comprehensive stratigraphic and geochemical databases have been developed for both of the beds. The extent of the bed with mined areas, structure contour, isopach, and overburden thickness maps for the Pittsburgh coal bed have been released as USGS open-file reports.

Jan 1, 1999

By Robert E. Blackett

To help local governments plan for long-term supplies of sand and gravel for buildings and infrastructure, the Utah Geological Survey is assessing natural aggregate resources (mainly sand and gravel) in the St. George, Utah area. Whereas much of the aggregate in the study area is adequate for road-base construction, high-quality aggregate for Port- land cement concrete is limited due to geology, and also due to land administration and environmental issues. Virgin River alluvial gravels southwest of St. George are generally poor sources of aggregate because they contain clasts of soft sediments and soluble minerals derived from Mesozoic rocks. Elsewhere, widespread secondary calcium carbonate (caliche), as rinds and matrix in gravel, lower the quality of material. Young river-terrace deposits in Fort Pearce Wash, and along the Virgin River above St. George are the primary sources of sand and gravel for the area. Alluvial fans on the east side of the Beaver Dam Mountains, and on the west side of the Hurricane Cliffs are also sources of aggregate. Stream-channel deposits associated with "inverted valleys" north of the towns of St. George and Hurricane, Utah, and older pediment gravels on the west flank of the Beaver Dam Mountains may be future sources of high-quality aggregate. Accelerated urban development during the 1980s and early 1990s has caused St. George and other communities in Washington County to encroach upon sand and gravel pits originally located in rural, undeveloped areas. Urban residents often view nearby sand and gravel operations as undesirable neighbors and pressure elected officials to close the pits. Pit closures effectively eliminate the remaining reserve from the sand and gravel resource base of the area. More- over, resources may also be lost as new homes are built upon undeveloped sand and gravel deposits. The St. George area is particularly susceptible to loss of aggregate resources because high-quality natural aggregate for construction is already in short supply. Moreover, most of the land in the study area is administered by the U.S. Bureau of Land Management and subject to various land-use restrictions. Much of this public land cannot be developed for mineral materials, such as sand and gravel, because of federal regulations protecting rare plants and animals, archaeological sites, and important watershed areas. Of particular concern to resource development are areas designated as Areas of Critical Environmental Concern, Wilderness Areas, and Wilderness Study Areas. Protection for Endangered Species is a critical element in all planning efforts. Those species present in the St. George area or in areas near- by include: the desert tortoise, southwestern willow flycatcher, Virgin River chub, and dwarf bearclaw poppy. As the St. George area is depleted and/or deprived of sand and gravel resources through extraction and urbanization respectively, construction costs will rise unless conservation measures are instituted. To avoid the loss of aggregate resources, the UGS is pursuing a program of data gathering and field surveying of surficial deposits to determine tonnage and quality of the remaining sand and gravel resources. The resource information from this program will help land planners, developers, and government officials make informed decisions concerning urban development throughout the region.

Jan 1, 2001

By Brian Stimpson

A recent study by the National Academy of Engineering concluded that if the U.S. Coal Industry is to double production by 1985 it must open 30 new 2,000,000 tons per year surface mines in the eastern states and 100 new 5,000,000 tons per year surface mines in the western states, in addition to major growth in underground mining. Major expansions in coal mining are also planned in other countries. Engineering geology can play an important part in coal mine development, operation and abandonment (Table I), and with the increasing scale of surface coal mining and the requirements of environmental legislation, it seems certain that engineering geology and geotechnics will play a growing role in surface coal mining.

Jan 1, 1976

By W. A. Mathews

We report on the progress of an automated mineralogical deportment of fluorine (F) in two portions of the Grasberg District for the development of metallurgical amelioration protocols for Cu sulfide concentrates. Fluorine detection limits in automated SEM technologies range from 1% (TIMA) to about 9% (QEMSCAN), however substitution in hydrophobic minerals or those reporting to concentrate is typically much lower (

Mar 2, 2022

By C. Green, J. Uhrie, C. Filippone, A. Guzman

A central aspect of heap leach management and recovery optimization is solution control. Insofar as each heap is unique in physical and metallurgical properties, it is essential to understand the hydraulic parameters that control the migration of solution on a case-by-case basis. Water Management Consultants, as part of an ongoing research effort for Phelps Dodge Process Technology Center, have adapted techniques of parameter estimation for application to data typically resulting from metallurgical column testing. The parameterization is completed within the context of a variably saturated flow model that allows interpretation of available hydraulic information collected during hydrometallurgical column tests. A novel interpretation approach is introduced to extract the necessary hydrodynamic parameters from typical hydrometallurgical data sets. Results from the application of the approach to standard metallurgical test data will be presented together with a discussion of the application of information gained to the design and operation of a heap.

Jan 1, 2002

By S. Hamilton

Borates are essential to life, and to many products that are essential to an acceptable standard of living. They occur naturally in seawater at an average concentration of five milligrams of boron per liter. Fresh water lakes, rivers, streams and ground water generally have concentrations of about one milligram boron per liter. Borates are also present in soil at concentrations ranging from 0.1 to three milligrams of boron per kilogram. Because most of that boron is locked into insoluble minerals, clay or organic matter, boron deficiency is more widespread than boron enrichment. Borates evaporate into the atmosphere from seawater, rain, snow and hot springs. In rain and snow, natural boron concentrations range from 0.002 and 0.1 milligrams boron per liter. All told, boron moves through the atmosphere at a rate of 5 Mt to 7 Mt/a (5.5 million to 7.7 million stpy).

Jan 1, 2005

The two candidates in the upcoming presidential election in the United States each say that they have their own solution to the nation?s energy problems - solutions that will increase the amount of energy available, lessen the nation?s dependence on foreign sources and reduce the amount of pollution released to the atmosphere. Democratic nominee Sen. Barack Obama and Republican candidate Sen. John McCain both advocate research funding for coal-to-liquids and clean coal technologies. McCain also supports increased oil and gas drilling offshore. And Obama has even made some noises in that direction, although his plan leans heavily on the increased use of renewable energy sources. The energy debate is not new to this election. Congress and whichever party is in the White House has for years been trying to craft a comprehensive energy policy. One difference in this latest debate is that the increased use of nuclear energy has gained more attention. Current President George W. Bush has said he favors the increased use of nuclear power as part of the nation?s energy package. And McCain said he supports the building of more nuclear power plants. Obama has not said much about that. The American public is also showing signs of changing its stance on nuclear energy. To be sure, images of Three Mile Island and Chernobyl are still alive in some minds. However, the American public has said it wants cheaper energy and they want it produced more cleanly. With nuclear, the nation can have both. In the United States, nuclear accounts for slightly less than 20 percent of the electrical power used (see interview with Gary Steele of Energy Fuels on page 27). Globally, that figure is about 15 percent. And there are several nations that derive better than half of their power from nuclear sources. Add to that the world?s increasing need for more energy and the future of nuclear is bright.

Jan 1, 2008

By K. R. Griffin

Atmospheric conditions underground are constantly changing and from a safety perspective, it is critical to identify when conditions are trending abnormally. Atmospheric monitoring in underground coal mines allows mine operators to analyze atmospheric conditions underground in real-time. Real-time monitoring can then be used to identify whether atmospheric conditions underground have become problematic. The implementation of a risk assessment and management process allows operators to then use a risk-informed decision making to identify comprehensive site specific ventilation parameters. Establishing risk-informed ventilation parameters and tracking conditions relative to these parameters, management can modify ventilation plans as mine conditions develop to manage evolving risks. Ventilation risk assessment and management allows developing atmospheric monitoring technologies to be fully utilized in order to increase safety standards in the United States. This paper reviews general risk assessment approaches, state of the art ventilation based risk assessment, and the risk assessment and management application within the United States regulatory framework.

Feb 27, 2013

By William P. Walsh

In December 1983 the author undertook an investigation in east Texas which was organized to learn the feasibility of applying geophysical techniques over shallow lignite deposits. The work embraced experimental high resolution seismic reflection and offset Wenner resisitivity sounds over three 4 to 4 mile test sections. This site also was sponsored by Woodward-Clyde Consultants (WCC) and a consortium headed by North American Coal Corporation. The principal objective of this investigation was to learn whether the aforementioned geophysical techniques could be applied over shallow lignite deposits (i.e. located at approximately 100' to 300' in depth) and consequently provide structural and stratigraphic information useful for resource and reserve characterization. A secondary objective was to determine if these same techniques could disclose the nature of the overburden and the distribution of ground water therein.

Jan 1, 1985

By R. Stocker

Flotation recovery of molybdenite particles finer than 15 micrones sharpy decreases with decreasing size. A totally hydrophobic latex agglomerant (UBC-1), which was previously reported to be very efficient in agglomerating hydrophobic fine coal, has been found to agglomerate fine molybdenite particles. The agglomeration takes place only in the presence of MIBC which is commonly used as a frother in molybdenite flotation. Adsorption tests confirmed that MIBC is adsorbed onto molybdenite. The effect of the agglomeration on flotation has been studied by floating fine molybdenite from mixtures with quartz using the UBC-l agglomerant and the MIBC frother. A significant improvement in the flotation of fine molybdenite has been observed in the presence of the UBC-l agglomerant. The best results have been obtained around pH 5.5 which corresponds to the iso-electric-point of molybdenite.

Jan 1, 1997

By James Charles McHardy

During 1980-2000, the Florida Phosphate industry will deplete its Central Florida Polk County reserves. As a result, new mines will be built in the ?so-called? Southern Florida Reserve areas. These new mines will require new mining, beneficiation and tailings disposal technologies in that the southern reserves have different characteristics than have been encountered in the Central Florida deposits furthermore, government regulations will necessitate the development of new tailings and clay disposal methods. This paper reviews these challenges for the phosphate industry and how these opportunities can be expected to effect plant design and plant operating practices.

Jan 1, 1981

By Robert D. Coyle, David L. Emmons

Introduction The Cove gold-silver deposit is located in Lander County, NV about 50 km (30 miles) southwest of Battle Mountain, NV (Fig. 1). The deposit is in the north-central part of the Fish Creek Mountains within the McCoy mining district. Gold was first discovered in the McCoy district in 1914 by Joseph H. McCoy (Vanderburg, 1939). From 1928 to the early 1930s, minor production occurred from shallow underground workings. Total gold production was less than 311 kg (10,000 oz; Stager, 1977). The district was inactive until the mid-1960s when it was explored by Bear Creek Mining, Summa Corp., Houston Oil and Minerals Corp., Gold Fields, and Tenneco Minerals. Tenneco began a detailed reevaluation of the McCoy deposit in the fall of 1984. Tenneco's decision to place the deposit into production was based on a geological reserve of 8.7 t (280,000 oz) of gold (Kuyper, 1987). Subsequent exploration and development drilling of the McCoy skarn deposit has more than doubled the mineable skarn reserves to 19 t (615,000 oz) of gold. In September 1985, Tenneco began development work on the McCoy gold-skarn deposit. The project is an open-pit, heap leach mine. The first gold was poured in April 1986. Echo Bay Mines acquired Tenneco's precious metals properties in October 1986. The mining operation and district exploration started by Tenneco is continuing under the Echo Bay's ownership. The Cove deposit was discovered in January 1987 and production began in February 1988. The deposit will begin as an open-pit, heap leach operation. It will be converted into an open-pit and underground mine with a 9-kt (10,000-stpd) mill. Geologic setting The Cove gold-silver deposit is situated on the east flank of the Fish Creek Range. Surface elevations range from 1460 to 1680 m (4800 to 5500 ft). The deposit is 1.6 km (1 mile) northeast of the McCoy gold-skarn deposit. The Cove deposit is hosted by the Augusta Sequence of Triassic age. Three formations of the sequence are mineralized at the Cove. In ascending order they are the Favret, Panther Canyon, and Augusta Mountain formations. The Favret formation is a gray, locally silty limestone that is commonly fossiliferous. The base of the formation is not exposed. Exposed and drilled intervals are more than 60 m (200 ft) thick. Conformably overlying the Favret formation is the Panther Canyon formation. This formation is 215 m (700 ft) thick and consists of a siliclastic and carbonate sequence of conglomerate, quartzite (sandstone), mudstone, limestone, and dolomite. It is a distinctly coarsening-upward sequence of rocks. The top of the unit is conglomerate with chert and quartzite clasts up to 150 mm-diam (6 in.-diam). The Augusta Mountain forma-

Jan 8, 1988

By J. R. Allen

Environmental laws and regulations have proliferated over the last two decades. 1/ Within the last year, Congress has dramatically expanded the scope of the Superfund program 2/ and has enacted significant new amendments to the Clean Water Act.3/ In addition, EPA has shown no signs of slackening the pace at which it promulgates new regulations to implement statutory programs. The agency projects that over the next few years it will issue approximately 275 new regulations under the statutes it implements. 4/

Jan 1, 1988

By Z. J. Hladysz

The Hladysz Rock Tester was developed at the South Dakota School of Mines as a portable rock strength tester. The hand held device is placed against a rock surface and struck by a hammer. The impacted force causes a steel ball in the device nose piece to indent the rock and simultaneously indent a standard steel bar also contained in the nose piece. By comparing the two indented diameters the compressive strength of the rock can be calculated using laboratory determined correlation coefficients.

Jan 1, 1984

By James A. Finch, Xiang Zhou, Yue Hua Tan

Widely used as collectors for nonsulfides, amines also show some frothing properties. Evaluating frother functions of amines and their combination with conventional frothers addresses whether one reagent delivering both collector and frother functions compromises the efficacy of either. From the findings, whether blending with frother confers any benefit requires knowledge of the residual amine concentration. If it is below about 10 ppm, blending eliminated coalescence, but there appears to be no benefit if the concentration is above 15 ppm.