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By Harold W. Lipper

A NEW record was set for helium shipment in 1962 for the 13th successive year. For the first time since 1949, the production of helium from natural gas at Bureau of Mines plants was less than in the previous year. The Bureau shipped 599.5 million cubic feet, 9 percent more than the 1961 volume, and produced 680.9 million cubic feet-a decrease of 6 percent from the record set in 1961. The Bureau added 77.2 million cubic feet to the volume stored for future use. Of the total 524.6 million cubic feet in storage, 522.4 million cubic feet is accumulated excess production from Bureau of Mines plants. The remaining 2.2 million cubic feet was purchased during 1962 from industry under the helium conservation program. The first two of five private plants began production in December to recover helium for conservation storage and ultimate use. A 425-mile pipeline system to transport helium from the five private plants to the Cliffside field was constructed by the Bureau at a cost of about $8 million.

Jan 1, 1963

By Harold W. Lipper

BUREAU OF MINES helium plants produced a. record-breaking 477 million cubic feet of this essential element in 1959. The supply of helium was less than the demand before operations were resumed at the Navajo plant in July and begun Sit a. new plant at Keyes, Okla., in August. Helium was in abundant supply after August, and the informal allocation system which had been in use intermittently since 1955 was discontinued Delivery of 26 new tank cars in August and September increased the total in the tank-car pool to 163. Defense and space agencies and the Atomic Energy Commission continued to use more helium in their operations and research.

Jan 1, 1960

By Harold W. Lipper

Helium production and shipment reached new peaks in 1.361. The Bureau of Mines produced 727 million cubic feet, 13 percent more than the 1960 record, and shipped 552 million cubic feet, 16 percent more than the 1960 record. Production exceeded demand for the third successive year, enabling the Bureau of Mines to add 174 million cubic feet to the volume stored underground for future use. At the end of 1961, the total volume of helium in underground storage in the Clifside gasfield was 44-7 million cubic feet. Contracts to implement a long-range helium conservation program were completed with four companies, obligating all the contracting authority of $47.5 million a year made available by the Congress. The four companies will finance, build, and operate helium extraction plants to recover from natural gas an annual average of 3.1 billion cubic feet of helium that would ordinarily be wasted when the helium-bearing natural gas is used for fuel.

Jan 1, 1962

By AIME AIME

TRANSFER to the Bureau of Mines of the responsibility for conservation and production of helium, and announcement that a proposal has been made to the President for commercial operation of the Los Angeles has attracted new attention to the helium program of the Government. The matter is one in which mining engineers, and the mining industry in general, have a peculiar interest. Helium is a byproduct of the petroleum and natural gas industry. It is found in certain of the natural gases which have themselves been discovered, in the main, in the search for oil. If it is to be produced on a large scale, the conservation and development of the fields will necessarily be done by the men of the oil and gas industry. There is no known or expected source of supply of quantities of commercial importance save in the natural gas fields. Not all gas wells supply helium and none of them supply it in important percentages. If it were necessary to prospect a field, develop it, lay pipe lines and build production plants for the helium alone, the cost would be prohibitive. On that basis helium would necessarily be restricted to essential war uses, where cost is subordinate to need. As a byproduct of the natural gas in certain, at least, of the fields in the United States there is distinct reason for anticipating that it may be produced in amounts and at a cost that will permit its regular use in commercial airships.

Jan 1, 1925

By G. R. Goldak

All of Canada's older uranium mining areas have been intensively prospected and known outcrops have been repeatedly examined. The only ground in these areas which has not been explored is that which is covered by water or other overburden. The discovery of new mines in these areas will, in the author's opinion, depend on the development of new geophysical or geochemical tools capable of locating uranium deposits which are-buried beneath tens to hundred of feet of overburden. Such tools would be extremely useful in Saskatchewan's Cluff Lake and Wollaston Lake areas. Uranium has recently been discovered in significant quantities in these regions but exploration is made extremely difficult and expensive by an almost uniform overburden cover. The author's experience has been confined to Canada but apparently a subsurface uranium prospecting method could be widely exployed in the western United States and Australia as well. Radon-222 measurements have been used for more than a decade on practically a worldwide basis in an attempt to obtain a useful method for subsurface uranium prospecting. It is well known that ha-222 produced by buried uranium deposits can diffuse through an overburden cover so that it can sometimes be detected at surface. An advantage of this method of prospecting is that Rn-222 can be detected with a simple scintillation, ionization or semiconductor detector. One of the essential weaknesses of the method is that the mean diffusion path length of Rn-222 is limited by its very short (3.8 days) half life. For a deeply buried deposit, vitually all of the Rn-222 atoms will decay before reaching surface and, therefore, such deposits cannot be expected to produce a detectable radon anomaly. Thus, except in unusual cases where groundwater or ground air flow assists the movement of radon towards surface, the depth of exploration is probably limited to ten or twenty feet of overburden cover. The high solubility of Rn-222 in water is also a source of difficulty. In an area where overburden covers bedrock with water saturation of the lower overburden levels, the radon will simply dissolve in the groundwater, and soil gas readings at surface will indicate falsely low

Jan 1, 1974

By Henry P. Wheeler

H ELIUM (chemical symbol: He) is a member of a family of normally gaseous elements, which, because of their zero valence and corresponding lack of chemical activity, are called the "noble" or "inert" gases. It is a monatomic element with an atomic number of 2, and it exists naturally in two stable isotopic forms-He3, with an atomic mass of 3.0170, and He4, with an atomic mass of 4.0039. With the exception of a trace (10-6 percent) of He3, all of the naturally occurring helium is He4. Two unstable isotopes-He5, with atomic mass 5.0137, and He6, with atomic mass 6.0208-are listed by various scientists, but the existence of He5 is questioned by some of them. He6 is radioactive, with a half-life of 0.8 second. Helium was discovered in 1868 in the gaseous atmosphere surrounding the sun. Although several scientists studied the solar chromosphere that year, it is generally agreed that J. Norman Lockyer of England should be credited with the discovery of helium, which he named, deriving the word from "helios," the Greek name for the sun. It was not found on earth until March 1895, when William Ramsay of London produced a small amount from a sample of cleveite, a uranium-bearing mineral. In 1905, H. P. Cady and D. F. McFarland of Kansas found helium in natural gas produced from a well near Dexter, Kans., and for the first time a large source of helium became available.

Jan 1, 1952

By Adnan A. Malik, Tadashi Maejima, Jiro Kuwano

"Previous studies revealed that the helix deflection reduced the end bearing capacity of screw pile in dense ground even if the installation process is completed with minimal soil disturbance. The ultimate end bearing capacity in dense ground is difficult to achieve during the full-scale pile load test due to the limitation of the loading system. Therefore, in the present study, model scale of testing is selected to investigate the effect of helix deflection on load settlement behavior of single helix screw pile under increasing stress level. It is observed from the test results that the applied surcharge pressure, which is used to simulate the effect of stress level, is decreased with increase in model ground thickness. This decrease in the stress level is due to the frictional resistance between the container wall and sand. It is also observed that the end bearing capacity of screw pile increases with the increase in stress level but at gradually decreasing rate. The test results indicated that the helix deflection during the pile load test should not be more than critical deflection (0.72 mm average) of the helix to avoid any reduction in the end bearing capacity of screw pile. The helix deflection, which is measured after the pile load tests are also compared with the equations of flat circular plate having uniformly distributed load over the plate with simply supported and fixed inner edges.INTRODUCTIONThe screw pile consists of a central steel shaft with one or more helices attached at different location on the central shaft. The installation mechanism of screw pile consists of torque and pushing force. The screw pile installation mechanism can affect the unit weight of the ground during its installation. This effect is small in cohesive soils but it is quite noticeable in loose to medium dense sands (Adams 2011; Santos et al. 2013). The pushing force should be controlled in such a manner that pile penetration should be at least 80% of the pitch of the helix, during each revolution (Perko, 2009)."

Jan 1, 2017

By M Barden, G Lane, B Quilliam

NQ Minerals PLC, through Hellyer Gold Mines Pty Ltd, plans to reprocess the contents of the Hellyer tailings dam to produce lead/silver concentrate, zinc concentrate and pyrite concentrate (containing Au and Ag). This paper discusses the project development, mineralogy, metallurgy and chemistry of processing Hellyer tailings and the associated environmental benefits. The Hellyer and Fossey orebodies were volcanic hosted polymetallic massive sulphide deposits located within the Mount Read volcanic arc of western Tasmania. Mineralisation was hosted in massive sulphide (pyrite) and comprised predominantly of sphalerite, with lesser galena, chalcopyrite and arsenopyrite. The Hellyer orebody was mineralogically complex (fine grained) and was treated through differential flotation with initially modest recoveries. Fossey ore processing characteristics were similar to those of Que River ore and simpler than Hellyer but treatment still resulted in significant grades in flotation tailings. CITATION: Lane, G, Barden, M and Quilliam, B, 2018. Hellyer tailings – complex mineralogy but higher grade than many ore bodies, in Proceedings Complex Orebodies Conference 2018, pp 35–38 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Viney K. G, Molinia A. B

The Hellyer Pb-Zn-Ag orebody in western Tasmania was discovered in 1983, and mine production at a rate of 250 000 tonnes/yr commenced in 1987. Expansion to 1 million/yr will be completed by early 1989. Exploratory development to gain access to the orebody, to provide a 20 000 tonne bulk sample for pilot plant work and to confirm mining conditions and orebody continuity was undertaken using conventional drill and blast techniques and large diesel trackless equipment. A ventilation shaft was raisebored. Development in this phase totalled 2 815 m and provided a sound basis for rapid expansion of the mine.

Jan 1, 1988

By Will D. P

A 328 m, 2.4 m diameter raise-bored shaft has been equipped with a modular ladderway system to provide a second means of egress from Aberfoyle's Hellyer Mine in Tasmania. The modular ladderway consists of platforms, ladders and service pipes assembled at the surface and progressively lowered down the shaft. This system provides a rapid, safe and economical non-entry approach to equipping a shaft. The modular construction and single suspension allows for future extension or for reuse in another shaft.

Jan 1, 1988

By A. B. Cecala

Video technology coupled with data logging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. These techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties and tasks. The Helmet-CAM is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a data logging dust monitor that are worn by a miner in a backpack, safety belt, or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data files are downloaded to a computer and then merged together through a NIOSH-developed computer software program called EVADE (Enhanced Video Analysis of Dust Exposure). By providing synchronized playback of the merged video footage and dust exposure data, the EVADE software allows for the assessment and identification of key work areas and processes, as well as work tasks that significantly impact a worker?s personal respirable dust exposure. The Helmet-CAM technology has been tested at a number of metal/nonmetal mining operations and has proven to be a very valuable assessment tool. Mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed EVADE software will be available for download at no cost on the NIOSH website.

Feb 27, 2013

By J. R. Patts, A. B. Cecala, E. J. Haas

Exposure to respirable crystalline silica (RCS) remains a serious health hazard to the U.S. mining workforce who are potentially exposed to RCS [1,2] as various ore bodies are drilled, blasted, hauled by truck, crushed, screened/sized and transported to their destinations. To examine a method for assessing RCS exposure using a NIOSH-developed video exposure monitoring (VEM) technology (referred to as Helmet-CAM), video and respirable dust concentration data were collected on 80 miners across seven unique mining sites. The data were then collated and partitioned using a thresholding scheme to determine exposures that were in excess of 10 times the mean exposure for that worker. Focusing on these short-duration, high-magnitude exposures can provide insight into implementing controls and interventions that can dramatically lower the employee’s overall average exposure. In 19 of the 80 cases analyzed, it was found that exposure could be significantly lowered by 20 percent or more by reducing exposures that occur during just 10 minutes of work per eight-hour shift. This approach provides a method to quickly analyze and determine which activities are creating the greatest health concerns. In most cases, once identified, focused control technologies or behavioral modifications can be applied to those tasks.

By J. R. Patts, A. B. Cecala, E. J. Haas

Exposure to respirable crystalline silica (RCS) remains a serious health hazard to the US mining workforce who are potentially exposed as various ore bodies are drilled, blasted, hauled by truck, crushed, screened, and transported to their destinations. The current Mine Safety and Health Administration (MSHA) permissible exposure limit (PEL) for RCS remains at approximately 100 μg/m3 , but it is noteworthy that the Occupational Safety and Health Administration (OSHA) has lowered its PEL to 50 μg/ m3 (with enforcement dates staggered through 2022 for various sectors), and the National Institute for Occupational Safety and Health (NIOSH) has held a 50 μg/m3 recommended standard since 1976. To examine a method for reducing RCS exposure using a NIOSH-developed video exposure monitoring (VEM) technology (referred to as Helmet-CAM), video and respirable dust concentration data were collected on eighty miners across seven unique mining sites. The data was then collated and partitioned using a thresholding scheme to determine exposures that were in excess of ten times the mean exposure for that worker. Focusing on these short duration, high magnitude exposures can provide insight to implement controls and interventions that can dramatically lower the employee’s overall average exposure. In 19 of the 80 cases analyzed, it was found that exposure could be significantly lowered by 20% or more by reducing exposures that occur during just 10 min of work per 8-hour shift. This approach provides a method to quickly analyze and determine which activities are creating the greatest health concerns. In most cases, once identified, focused control technologies or behavioral modifications can be applied to those tasks.

By A. B. Cecala

Video technology coupled with datalogging exposure monitors have been used to evaluate worker exposure to different types of contaminants. However, previous application of this technology used a stationary video camera to record the worker?s activity while the worker wore some type of contaminant monitor. these techniques are not applicable to mobile workers in the mining industry because of their need to move around the operation while performing their duties. the Helmet-Cam is a recently developed exposure assessment tool that integrates a person-wearable video recorder with a datalogging dust monitor. these are worn by the miner in a backpack, safety belt or safety vest to identify areas or job tasks of elevated exposure. After a miner performs his or her job while wearing the unit, the video and dust exposure data filesare downloaded to a computer and then merged together through a NIOSH-developed computer software program called enhanced Video Analysis of Dust exposure (eVADe). by providing synchronized playback of the merged video footage and dust exposure data, the eVADe software allows for the assessment and identificationof key work areas and processes, as well as work tasks that significantlyimpact a worker?s personal respirable dust exposure. the Helmet-Cam technology has been tested at a number of metal/nonmetal mining operations and has proven to be a valuable assessment tool. mining companies wishing to use this technique can purchase a commercially available video camera and an instantaneous dust monitor to obtain the necessary data, and the NIOSH-developed eVADe software will be available for download at no cost on the NIOSH website.

Sep 1, 2013

By S. M. Pickering

Banks frequently manage large privately owned mineral land trust accounts for estate heirs. The bank has a fiduciary obligation to follow the “Prudent Man Rule”, which requires that trust properties be managed at least as well as a prudent and knowledgeable owner could. However, banks may not have internal staff proficient at mineral property values, lease contracts, royalties, mining practices, etc. This is an opportunity for experienced geologic consultants and certified minerals appraisers to provide needed help. Items valuable to Trust managers may include: 1. Marketing privately owned mineral trust lands to mining or oil & gas firms, assuring competitive offering prices and terms; 2. Negotiating favorable new mineral lease and purchase-option contracts; 3. Monitoring progress of mining, royalty payments, land reclamation, and environmental clean-up work; 4. Balancing future mining income with later industrial, commercial or housing development, timber harvest, etc.; 5. Assuring that Depletion Allowance tax advantage is taken for actual mine royalty payments, but not for annual non-mining lease (rental) income; 6. Appraising in-ground mineral value for bank audits, estate tax valuations, and equitable property division between heirs; and 7. Serving as expert witness, representing the legal interests of the bank, trusts, and the mineral heirs in litigation. Banks do welcome reliable advice which assists them in achieving the “Prudent Man Rule” and improving mineral income to their land Trust accounts.

Jan 1, 2002

By A. J. Abraham, K. E. Seitz, J. D. Humphrey

Caterpillar has led the way for sound reduction in off highway trucks (OHT) used for mining. In 2000 Caterpillar introduced the 793CXQ sound reduction OHT (Figure 4) to meet local noise level demands in the Hunter Valley near Sydney, Australia. The sound level of the mining equipment in the Hunter Valley is being reduced to pre-serve the quality of life for the residents of the area. To meet the levels established required a major redesign of the 793C, as a result the sound power level was reduced by 9 dB (A), which is a less than 1/8the original sound level.

Jan 1, 2004

By R. Wirth, B. Orberger, C. Wagner, A. Tudryn, B. Baptiste, S. Miska, Université Paris-Sud

Banded iron formations (BIFs) comprise complex textures and mineralogy, which result from fluid-rock interactions related to high and low temperature alteration. The initial iron oxy hydroxide mineralogy and associated phases such as carbonates, quartz, apatite and phyllosilicates were transformed leading to an upgrading of these BIFs into the world’s largest source of iron ore. In low-grade BIFs, a large part of the iron is related to micro- and nano- metric iron-bearing inclusions within micrometric quartz and/or carbonates (mainly dolomite). We studied laminated jaspilitic BIF samples from a drill core containing 26.71 wt.% total iron, 0.2 wt.% SiO2, 0.32 wt.% MnO, 15.46 wt.% MgO, 22.32 wt.% CaO, 0.09 wt.% P2O5, < 0.05 wt.% Al2O3, 0.15 wt.% H2O and 34.08 wt.% CO2 (Aguas Claras Mine, Quadrilatero Ferrifero, Brazil). Bright rose coloured dolomite and quartz bands alternate with massive specular hematite bands. Raman spectroscopy, X-ray diffraction and FIB-TEM analyses reveal that the micro- and nanometric inclusions in dolomite are mainly hematite and minor goethite, partly occurring as clusters in voids. Curie Balance analyses were carried out at different heating steps and temperatures on whole rock samples and a synthetic mix of decarbonated sample and pure dolomite. X-ray diffraction on the products of the heating experiments shows that that hematite is stable and new phases: magnesioferrite (MgFe2O4), lime (CaO), periclase (MgO), portlandite (Ca(OH)2) and srebrodoskite (Ca2Fe2O5) were formed between 680°C and 920°C. These finding gives hints to optimizing the beneficiation process, as the presence of hydroxyl ions bearing goethite micro- and nanoinclusions lowers the sintering temperature. Prior separation of coarse hematite and barren dolomite and quartz, followed by lower temperature sintering of the inclusionbearing dolomite/quartz leads to transformations into phases with higher magnetic susceptibilities (such as hematite and magnesioferrite). The entire Fe and Fe/Mg oxide feed (the priorly separated fraction added to the sintered fraction) can then pass through wet-high intensity magnetic separation after crushing.

Jan 1, 2016

By M. W. Bartley

DURING the field season of 1938, the Ontario Department of Mines assigned a combined geological and geophysical survey patty to the investigation of the location, genesis, structural relationships, and economic possibilities of the hematite deposits at Steeprock lake. The investigation was carried out by detailed mapping of the rock exposures and a magneto-metric survey of the drift-covered portions of the area. This was supplemented during the winter of 1938-39 by further geophysical work conducted on the ice. Dr. A. A. Brant, of the Department of Physics, University of Toronto, was in charge of the geophysical work for the Department of Mines in the summer and for the Sterola Exploration Company in the winter. The writer supervised the geological examination. Scope of the Paper The present paper is an attempt to acquaint the members of the Institute with the structure and mode of occurrence of the deposits, since many people are of the erroneous opinion that they are analogous to the Mesaba and Michigan deposits. It is hoped that, from this discussion, they may be able to draw some conclusions of their own regarding the nature of the deposits, and the importance and future possibilities of the region.

Jan 1, 1939

By Chang Wei, Zhigan Deng, Minting Li, Cunxiong Li, Gang Fan, Xingbin Li

Iron precipitation occupies a vital position in the metallurgy industry, especially for treating iron-bearing sphalerite in hydrometallurgical processes. This paper emphasizes techniques for removing iron from high-iron sphalerite via hematite precipitation, and describes the results of research performed to examine ferrous oxydrolysis and precipitation. The behavior and mechanism of conversion between the iron phase and hematite residue at elevated temperature under pressure is ascertained by investigating the dissolving characteristic and thermodynamics stable area of hematite at sulfate system. The results show hematite precipitation went through the process of crystallization, dissolve, oxidation and precipitation of ferrous sulfate, and the overall iron precipitation was determined to be controlled by the rate of ferric sulphate hydrolysis rather than the oxidation of ferrous sulphate or the re-dissolution of ferrous sulphate crystals, or the transformation of basic ferric sulphate.

Mar 1, 2018

By Edouard Asselin, Tasawar Javed

The precipitation of hematite from ferric sulphate - cupric sulphate - lithium chloride acidic solutions was studied in a batch reactor. The effect of several variables on the extent of hematite precipitation as well as on its crystallinity and purity was investigated. The variables studied include: initial ferric concentration (1.5 - 30 g/L), retention time (0 - 12 h), initial sulphuric acid concentration (0 - 30 g/L), temperature (150 - 220 °C) and chloride concentration (0 - 25 g/L). The results show that hematite is preferentially precipitated at lower initial iron concentrations. Longer retention times increased the fraction of hematite in the precipitates but did not affect its crystallinity to a significant extent. On the other hand, higher temperatures increased the purity and crystallinity of the hematite. At lower acid concentrations hematite and goethite were precipitated. However, only hematite was precipitated when the initial acid concentration was > 12.5 g/L. Better crystalline hematite was formed at lower acidities. Increasing chloride concentration increased the amount of hematite and decreased the amount of iron sulphate hydroxide phases, but did not affect the crystallinity of the hematite.

Jan 1, 2015