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By Hiland G. Batcheller

HISTORY shows that the nation which makes the most steel is the most likely to win wars. Today the course of war shows that the nations which get there first with the most steel of the right kind will be the ones to win. Not only the most steel, mind you, but the right kind. Adequate production, which was enough for victory before the days of totally mechanized warfare of 1943, must now be accompanied by still better quality as well as more effective distribution. Further, both production and distribution must be flexible enough to permit rapid shifts from one weapon to another for use in varying elements in varying geographical areas. Thus the problem of making enough steel of the right kind at the right time in the face of changing requirements dictated by experience has been and will remain highly complex. This does riot permit us to ease our restrictions on nonessential use. War is a complex business, like the job of making steel for war. Each time we solve one problem, another pops its head up. Yet we are making some progress.

Jan 1, 1943

By William Gleason

"It is the largest mining exhibition in the world that attracts thousands of attendees from around the world to Las Vegas, NV once every four years. Despite the recent struggles in the mining industry, MINExpo International 2016 promises to be as big as ever. In the following pages, Mining Engineering takes a look what some of the more than 1,800 companies plan to showcase during the three-day exhibition.CaterpillarCaterpillar will support MINExpo 2016 with an exhibit showcasing machines, technology, expertise and practical knowledge that miners can apply to help address their cost, productivity and efficiency challenges in today’s mining environment.Caterpillar will once again occupy the largest space at the event and will showcase both surface and underground machines, but the talk at the booth will focus on how Cat technology and know-how combines to help mining operations address and solve the issues that are most important to them. The main stage in the exhibit will feature presentations describing how mining companies, Cat dealers and Caterpillar work together to improve operations.“The challenge for all in the mining industry now is to optimize operations — to drive costs down while creating sustainable businesses that can weather downturns,” said Caterpillar Resource Industries group president Denise Johnson. “We believe that through our expertise and the knowledge of our dealers —combined with innovative technologies and our growing data analysis capabilities — we can help them not only survive, but thrive in these challenging times.” Johnson was selected by the National Mining Association (NMA) to chair MINExpo 2016. “Chairing this show is a great honor, and it’s a testament to Caterpillar’s partnership with this critical industry,” she said. “We’re proud to be a long-time supporter of the NMA, and we are excited to participate in another MINExpo. It’s an opportunity for us all to learn from each other how to increase productivity, control costs and improve overall operations.”Surface mining displays. The surface mining section of the Caterpillar exhibit will showcase the new MD6420C rotary drill. This is autonomy ready and optionally equipped to leverage the safety and productivity benefits of Cat MineStar Terrain. This high-precision drill management system optimizes utilization and improves drilling and blasting operations by accurately guiding the operator and improving precision of hole placement and drilling depth — and the next step is fully autonomous operation, Command for drilling. The third-generation drill incorporates proven Cat components throughout for superior reliability and durability."

Sep 1, 2016

By Chee Theng

"So many talks, so little time.One of the toughest challenges associated with attending the SME Annual Conference and Expo is deciding how to allocate one’s resources. After accounting for keynote and plenary sessions, committee meetings, networking events, luncheons and exhibits, attending even one of the 109 technical sessions and more than 600 technical paper presentations can be a labor of love. Many, however, managed to make it to many of the sessions, including the mineral and metallurgical processing technical session on solvent extraction, ion exchange and electrowinning.At one point, that room was seated to near capacity, with a considerable number of the audience members standing by the walls at the back. Brittany Valera of Freeport-McMoRan Inc. was one who came early and enjoyed the session in its entirety. "Everything was pretty exciting," she said. "I really liked the modular plants. I think the future of mining, just like what we talked about in there, lies in thinking about things like remote locations, lifetimes of plants, anything that would be reusable and sustainable; and lower-cost and user-friendly would be really beneficial."Michael Moats, associate professor of metallurgical engineering at Missouri University of Science and Technology, started off the session by presenting on behalf of post-doctoral student Alex Luyima, who, like many before him, had been snapped up by industry and is now working for a secondary-metals refining company in Texas. Their team studied the nucleation and growth mechanism of copper on stainless steel from synthetic acidified copper sulfate in the absence and presence of chloride ions and three commercial organic additives: Hydrostar 4208, DXG-F7 and Cyquest N-900. Currenttime data were analyzed using known models, with reference to scanning electron microscope images. Good agreement was achieved between the models and SEM micrographs of deposits at a commercially relevant current density of 30 mA/ cm2. The addition of 20 mg/L chloride was found to increase the size and reduce the number of nuclei. The addition of 2.5 mg/L of each additive did not change the mechanism, but all three reduced the size and increased the number of nuclei, leading to more uniform coverage of the substrate with smoother deposits produced in twohour electrowinning experiments. N-900 had the best deposition coverage while DXG-7 was the easiest to dissolve."

Jan 1, 2014

Miners really are an optimistic bunch. Even with the dark clouds hanging over the global industry, mining professionals still turn out in droves at industry conferences. In February, more than 7,200 professionals attended SME?s Annual Meeting in Denver, CO, a record. And the following week, more than 30,000 people converged on Toronto, ON, Canada for the Prospectors and Developers Association of Canada (PDAC) meeting. For many small and junior mining and exploration companies the PDAC conference is a place to find potential investors in their projects. The Investors Exchange attracts several hundred companies, each showing off their properties to the many money types who wander the hall during the four-day conference.

Jan 1, 2013

Improvements in cost efficiency, noise control, environmental design and ergonomics ? the mining and construction industries are facing demands on many fronts. The international manufacturers of construction machinery are responding to these challenges, and they will be presenting their innovations in all these fields at bauma 2013. bauma, the international trade fair for mining and construction machinery, mining vehicles, and building material machines, takes place from April 15 to 21, 2013 at the Messe Munchen exhibition center in Munich, Germany. The last bauma, in 2010, attracted 3,256 exhibitors from 53 countries, and more than 420,000 visitors from more than 200 nations. Covering a total of 555,000 m2 (5.97 million sq ft) of exhibition space, bauma is one of the largest trade shows in the world. This year?s fair is expected to surpass the 2010 figures. Here are some examples of the new developments visitors can expect to see at the show.

Jan 1, 2013

By Joe Keane

DOUG HALBE: The kickoff speaker, and my unanimous choice, is Joe Keane. Joe was born in Butte, Montana, and began his association with the mining industry as an under- ground miner at age 16. Currently he is president of KD Engineering and Metcon Research. He had it lucky when he went to school because there were only 44 elements in the periodic table, I understand. [laughter] Here's Joe. JOE KEANE: I'm doing this under protest. Maybe we can start the slides. Mr. Halbe gave me this topic, but I don't like it. I don't like Mr. Halbe either [laughter] because of the way he shanghaied me into this. He called me up on the phone and said this is what you're going to speak about: "Five Things I Never Want to See Again in Plant Design," and I said, "Huh!" Then I started getting stuff from SME about how to make a presentation. I have decided to change the title to "More Than Five Things I Never Want to See in Plant Design," since you can't have a completely negative speech; you have to have other topics. So we will have some other, not completely nonrelated, topics to sort of break the tension. I tried to find a joke to open with. I talked to Omar Mutati. All of his jokes were either about Bill Clinton, our beloved President, or they were too filthy to say in a mixed group. [laughter] So I decided to start this out with a profound statement. The pro- found statement is, "The meek shall inherit the earth, but not the mineral rights," [laughter] by J. Paul Getty. J. Paul Getty was one of my favorite guys because when a real obnoxious reporter asked him one day, "How can I become wealthy?" he said, "Drill for oil and find it."

Jan 1, 1998

By Paul Klaric, Nicholas Bodley

Every blasting engineer or professional can attest to the age-old conundrum of obtaining accurate hole information on a large scale prior to loading explosive charges in a blast hole. Even though the benefits of QA/QC are well known and documented and are becoming increasingly important when digitizing and automating mining operations, the QA/QC process itself has not changed significantly over generations. The current methods where operators deploy measuring tapes of variable standards recording their subjective assessment of hole length on a paper blast map or manually transcribing to a tablet, are unreliable and non-auditable. Additionally, the process in its current form is time intensive, obtaining only moderate results and benefits, making it difficult or impossible to resource in today’s tight labour markets. Often only two data points, depth, and water presence, are captured when visiting the hole resulting in a high cost per bit of data. For these reasons, the process is seldom done on a large scale, let alone integrated. The QA/QC process in its current shape is a gap that will need to be addressed if autonomous blasting and mining is to become a reality.

Feb 6, 2023

By L., Ormsby

DRILLING and blasting practices in the Morenci open pit have undergone considerable modification in recent years. Changes in the character of the ground being mined, modifications of working conditions, and continuous experimentation have been the contributing factors.

Jan 1, 1950

By R. Blosser

Phelps Dodge introduced a process improvement model known as Quest for Zero in 2001. In 2004, the focus of Quest for Zero shifted from corporate-led initiatives to projects led by site personnel. The Hydrometallurgical Division at Morenci focused on two (2) significant process improvements: reducing electrolyte bleed and organic losses. In September 2004, Morenci kicked off a bleed reduction project to reduce electrolyte bleed by 45%. By the end 2005, electrolyte bleed was reduced by 55% through understanding and reduction of variance. Significant process changes made during this time period include changes in acid-addition strategy, reduction of uncontrolled bleed, and optimization of bleed placement. In April 2005, the organic reduction project began with the goal of reducing losses by 15%. Operational improvements during this project included improved organic recovery systems, mixer speed optimization, and picket fence installation. By the end 2005, this project reduced organic losses by 35% and current losses are 48% lower than at the start of the project. These projects and smaller Questfor Zero projects have resulted in sustainable annualized savings of $13 million in Morenci hydrometallurgical operations. Through the use of Six Sigma tools, process variances can be controlled and reduced.

Jan 1, 2007

By M Creech

During the 1990s, wider and more productive longwall panels were being introduced into the Newcastle Coalfield. The strata of the Newcastle Coalfield incorporate numerous massive sandstones and conglomerates, some of which formed the immediate roof of the coal seams being mined. The unexpected implications of introducing wider panels into this geological environment included more variable and increased subsidence, severe periodic weighting (with associated mid-face falls) as well as windblast.Subsidence prediction at the time was based on empirically derived data essentially relating subsidence to the width/depth ratio of the panel without accounting for actual widths, nor the impacts of variable geology. This approach required modification as locally derived data was gathered and reinterpreted.The interaction of massive strata located close to the roof of the mined seam resulted in dramatic implications for some of the operations. When associated with longwall goaf geomechanics severe periodic weighting events and crippling mid-face roof falls were the consequence. When associated with narrower panels and shortwall goaf geomechanics, mines in the region experienced aggressive windblast events. The relationships between the overlying massive strata, longwall panel geometry and the various risks encountered during this period is in the author’s opinion, the most concise still documented.As the extensive coalfields of Queensland turn to underground mining operations the relevance of these experiences cannot be underestimated. This paper will discuss recent developments as well as incorporating diverse subjects such as microseismic monitoring, low frequency radio emissions and ‘electrophonics’ as they relate also to the topic.Like Moriarty, massive strata can be disguised and can offend when you least expect. This paper documents a trail of crimes committed by conglomerate in the Newcastle Coalfield that were inflicted on the general public, miners and mining equipment. Although this paper concentrates on the criminal behaviour of conglomerate, this story is also relevant to other massive units such as coarse sandstones that may be more difficult to identify and apprehend. Currently Moriarty remains at large and able to reoffend at any time, once again taking advantage of the unwary.CITATION:Creech, M, 2014. Moriarty was a conglomerate – experiences and implications of coal mining under massive strata in the Newcastle Coalfield, in Proceedings Ninth International Mining Geology Conference 2014 , pp 47–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

CHAIRMAN ALLEN: Gentlemen, I have been asked to call this meeting to order by Mr. Marchant, and am acting here temporarily in the absence of Mr. Nyman, who is unable to be with us. Mr. Nyman sends the following telegram: "Will not be able to be present at the Institute meeting. Serious illness of my father has made it necessary for me to remain in Salt Lake Please arrange substitute. Very sorry." In addition to having to pinch-hit for Mr. Marchant and President Nyman, I am here representing the Governor of the State of Colorado also who is unable to be here. The Governor of Colorado is a very busy man. His appointments are made months ahead. We only got word of the possibility of his addressing this meeting yesterday morning, and I went over to the Governor's office this morning to see if there was any possibility of getting him here, but he had been booked up for two months ahead of this time to appear at the convention of the Veterans of Foreign Wars in Trinidad, Colorado, where he is today, and which makes it impossible for him to attend this meeting. I know that he would have liked to have been here with you, as there is not any doubt but what the Governor of Colorado has the interests of the mining industry at heart. This was manifested last week when he called a meeting of representative men of the different lines of industry so that we could arrive at some results and some arrangements to see if it was possible to get at the bottom of the condition causing our bad times, and the appointment of commit- tee groups to find out what these problems were and to see if they could get any possible solution to them. The meeting was adjourned with the suggestion that those who were present would among themselves select such committees to investigate the conditions of the coal mining industry, and offer suggestions for betterment.

Jan 1, 1938

PRESIDENT SHOTT: Gentlemen, the meeting will now come to order, please. Members of the Institute: It is with great pleasure and honor that we welcome you to the thirty-ninth regular meeting of the Rocky Mountain Coal Mining Institute. I assure you that Mr. Krippner, the General Chairman, and his associates have an outstanding program in store for you, and trust it will be of much interest to the industry. I note by the program they have me slated for an opening address, but I am going to defer that, proceed with the remainder of the program, and endeavor to go on schedule and keep matters on schedule as outlined on our program. The first item on the program is the reading of the minutes of the thirty-eighth regular meeting by the Secretary. I might say that it has been customary in the past that we omit the reading of the minutes. If that is not agreeable, we will read them; otherwise, I would like for someone to make a motion that we dispense with the reading of the minutes, inasmuch as they are published in our annual report each year. What are your wishes?

Jan 1, 1941

By William M. Wallace

Mr. Chairman and Gentlemen: The subject, "Shake It for Results," may or may not suggest just what is to be shaken, or just what results are to be obtained. I can assure you that if you are thinking about anything outside the realm of pure mining application you have come to the wrong meeting, and if this be the case, you have come to hear a subject discussed that I am not prepared to undertake-at the moment, at least. At the very beginning of time, results were definitely obtained by shaking. If you will recall, Eve shook a certain tree of forbidden fruit-need I recount to you the results that were, and are still, being credited to that bit of engineering? To get closer to the subject at hand, it is the intent of this paper to touch generally on the shaking, principally the vibratory shaking, of materials on a piece, or pieces, of perforated metal or screen cloth. Through the evolution of such a motion we find that great strides have been made toward a highly efficient "operation which is an essential factor in the mining world of today. The object of the shaking motion is to more efficiently separate one size material from another, according to the openings in the screening medium over which it is passed. Sizing is an important operation in every ore dressing, coal prepara¬tion or other mineral-preparing plant for reducing the product to a form more concentrated or more convenient for utilization than that in which it was mined. In coal preparation, market requirements, convenience, custom, and efficiency in combustion necessitate grading mined coal by sizes. All ore-dressing or coal preparation plants therefore must have what is called screening, sizing, or grading apparatus.

Jan 1, 1941

The final session of the meeting was preceded by a movie, "Contact That Kills," which was a color film clearly pointing out various causes of electrical accidents in mines and how such accidents could he prevented. This film was made underground and produced by the U. S. Bureau of Mines for use in teaching accident classes. President R. R. Williams, Jr., called the meeting to order and introduced Mr. Leif Arentzen of the Lee-Norse Company, Charleroi, Pennsylvania, who spoke on "Coal Mining in Australia." The text of his address is as follows: "I arrived in Australia in February of this year-my father sent me over there for an installation. He preceded me as he does in most things, and set up a showing of our machine in Australia. We had 200 of the top level coal mining men visit this showing. They were interested in what the Americans are doing and what the American manufacturer had to offer them. Conditions in Australia are very similar to our mining conditions in the United States and they have looked to us, the coal industry in general, because we have the know-how in answering some of their problems. They feel that European methods and their type of machines are too inadequate to cope with their conditions. My visit was to South Wales, 60 miles south of Sidney. Their mining operation resembled mining coal in Florida. The work is on about a 500-ft. elevation about three miles from the ocean and when you turn around and see about 30 miles of beach, it is quite a picture - the Pacific Ocean is so blue. The coal seam is about ten feet of relatively clean coal. Labor relations are very, very taught right now. They are agitated by a strong Communistic influence and their weekly publication is known as the ?Common Cause,? which is against mechanization of coal mines." Mr. Arentzen enlarged on the fact that America was the example they held before them and described the Australian coal men and their character.

Jan 1, 1959

By John E. Willson

Typical of southwestern Wyoming are coal structures that dip from 4 degrees to 17 degrees. Those at the Reliance and Winton mines of the Union Pacific Coal Company average 9 1/2 degrees and 15 degrees, respectively, and dip almost directly to the west. By using a hoist for main haulage. a method of mining has been developed whereby four places are driven on the pitch of the seam. Slightly upgrade from the strike at intervals of 300 feet, a two-entry system is driven to the north and to the south. In both fields, which are non-gassy, an exhaust system of ventilation is used. Slope, manway, and lower or haulage entries are placed on the intake. Two air-courses and upper or breaking entries are placed on the return. A retreat system of mining is used exclusively. From the opening of its first coal mine, in the year 1868, until 1923, when the Joy Loader was introduced into the Union Pacific Coal Company's operations, slopes, aircourses and manways were driven by hand. Development work was conducted on the night shift or off shift, and the main hoist was used for haulage. The slope was driven down the pitch with crosscuts turned at intervals of 75 feet and entries at 230 feet. Connections to the workings above were made by driving up the pitch 75 feet. Mule haulage was used to furnish cars to the hand loaders driving planes up the pitch. A sheave was placed at the upper end of the plane with a 1 1/4¬ inch hemp rope doubling around it and having one end attached to the car and the other to the mule. The mule, pulling downhill, raised to the working face a small wooden car of one-ton capacity.

Jan 1, 1941

The third session of the Rocky Mountain Coal Mining Institute was called to order by Edward G. Fox, President of the Bitumious Coal Operators' Association, Washington, D. C., at 9:M A.M. He stated he had enjoyed being present at the Institute the past two years, and was honored to be asked to preside at this morning's session. Mr. Fox introduced Cloyd M. "DOC" Smith, Vice President of World Mining Consultants, Inc., Washington, D. C., whose talk, "World Trade in Coal" was illustrated with a number of graphs. (See Index.) M. E. "Shorty" Wade, Assistant Purchasing Agent, Kaiser Steel Corporation, Fontana, California, was introduced and gave a paper on "What Is Required to Realize Profits Through Purchasing." (See Index.) Mr. Fox suggested that all members take an active part in their association. He stated that much more can be done in association work than as a lone wolf. He urged all to support their organization and stay with it. It is for each member's good and not for the good of a few. Carl G. Schilbe, District Manager, Jeffrey Manufacturing Company, Columbus, Ohio, was introduced, and he presented a paper on "Results of a Study in Belt Idler Design -The Perma-Seal Idler." This paper was illustrated with a number of slides. (See Index.) "Operation of A-C Mines," was the topic covered by W. C. Painter, Service Engineer, Joy Manufacturing Company, Price, Utah. (See Index.) Each of the papers was well received, and presented a number of things valuable to all who heard them. Mr. Fox then turned the meeting back to President von Storch who read several announcements of committee meetings, and the meeting was adjourned at 11:30 A.M. for an afternoon of recreation before the banquet and dance that evening.

Jan 1, 1958

The Wednesday Morning Session of the Rocky Mountain Coal Mining Institute was called to order by Albert Keenan of the Thompson Creek Coal and Coke Company, Denver, Colorado, in the absence of the President. He introduced Edward Prostel of the University of Wyoming Natural Resources Research Institute, Laramie, Wyoming, who spoke on "Coal Utilization Work at the University of Wyoming." (Please refer to the index for printed text of the paper.) Following Mr. Prostel's talk, R. Park Lamborn of the National Mine Service Company, Pittsburgh, Pennsylvania asked Mr. Prostel two questions: (1) What -has been done in tar research? and (2) Has there been large scale research on brickets? Mr. Prostel stated that he could not say too much about the first question as this research was done in the petroleum department and he would prefer to have a chemist talk about it. As to the second question, the system of carbonization is a big project. There are many possibilities. At the University they are trying to do that in the same unit that produces the char. This system was introduced in Canada. The brickets are bound with sulphite liquor. Mr. Schloss asked Mr. Prostel to report on a project that they have been working on at the University, and Mr. Prostel stated that some time ago they began to experiment to see if it would be economically possible to dry coal at the mine (coal containing 30% moisture) and then ship it a distance of 130 miles to be used. Results are that it would be possible, but will require a considerable quantity. He felt it might be possible to operate such a scheme in a few years.

Jan 1, 1957

By Jacques B. Wertz

However excellent the geologic map of an area is, it can only show what is exposed on the ground. It cannot and should not generalize the information nor complete the picture by inference: this is left to the examiner. Consequently, it becomes justified for him to use all expressions of geologic structure in order to gain an additional dimension in geologic interpretation, and particularly so in mineral exploration. In previous studies related to Arizona, the known faults were the starting points and a host of interpolated, supporting geologic factors described in earlier publications ascertained the presence of a series of structural trends and lineaments found to be rather continuous and persistent, even though unsubstantiated by geologic maps. In present studies pertaining to the humid environment, with the same aim of seeking major structural trends and lineaments, the starting points are morphologic expressions such as straight lakes and straight segments of rivers, among others, because there generally is not enough geology available. An example is given herewith for an area that straddles the International Border, north of Spokane. In both semi-arid and humid environments, one observes that mineral deposits quite often occur close to the intersection of a major fracture or lineament with some secondary trend.

Jan 1, 1971

By Y Akiti, J Moller, E Esper, R Rugolo, A Pains

"Morro do Ouro Mine is a high tonnage/low-grade mine located in Paracatu, Minas Gerais State, Brazil. The mines move around 55 Mt of ore per year at an average grade of 0.4 g/t. The auriferous mineralisation of Morro do Ouro is related to hydrothermal fluids rich in arsenic (As), gold (Au), lead (Pb) and zinc (Zn). These percolated along favourable structures contained within phyllites of Upper Proterozoic age and defined a mineralised megaboudin which outcropped with 4 km extension and up to 2 km in width. The litologies in the interior of this structure are typically more deformed, sericitised and sulfidised, and exhibit the development of quartz boudins in the centre of the more deformed zones where are found the higher Au grades and the coarser sulfide crystals. Gold is preferentially associated with arsenopyrite, mainly occurring in fractures or aggregations of crystals and is rarely in solid solution or refractory. Over 90 per cent of the gold contained in the sulfide ore is free or extractable by cyanidisation. The current mineral reserve is 17.9 Mt at 0.403 g/t published at the end of 2012.In order to get a good grade estimation that represents the orebody more accurately a solids methodology was used to distinguish the different orebodies. Before 2011 the orebodies were worked with two domains relating to the weathered mantle. The B1 ore, which is oxidised, is located at the top of mineralisation, and is used to feed Plant 1. Underneath B2 ore, which is fresh sulfide bearing, represents over 30 years of production in Plant 2.In order to improve the predictability of gold grade estimation in geological modelling and to get a better predicting behaviour of each domain on the deposit, studies were carried out in which it was possible to show a correlation between elements and the mineralisation. One strong correlation and spatial distribution between Au and As, As and sulfur (S), Au and Pb, Au and Zn were found.Based on geochemistry, mineral correlations, amount of sulfide, structural deformation, texture of sulfides and the daily experience of the mine, it was possible to create solids that individualised bodies with similar mineralogical and chemical characteristics using the parameters listed above.After 2011, a new modelling concept was proposed and built with 11 different domains, compared with the previous, and with two more parameters: recovery acid neutralised capacity (ANC).Each of these bodies have different behaviours in mineral processing, like flotation and metallurgy. For example, bodies with pyrrhotite bring problems in the flotation, bodies with high arsenic do not recover well, bodies with high As with coarse texture have good recovery, bodies with fine texture do not have good adherence in production.In the present state of knowledge, protocols are being developed for bench testing to predict the recovery of each geochemical domain aiming to include these in the geological model for the parameter recovery. It is intended to create a field throughput in the model of ounces per hour, from each block of each domain to better predict the production, using the parameter recovery, Au and Bond Work Index (BWI).CITATION:Esper, E, Rugolo, R, Moller, J, Akiti, Y and Pains, A, 2013. Morro do Ouro geological model with a metallurgical view, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 67-74 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

The rich Tiller seam in southwest Virginia averages 10 to 15 ft in thickness. But because it is separated into two benches, mining engineers for years considered it neither physically nor economically feasible to mine. Profitable recovery of this coal has been made possible only by: full-seam mining with automatic machines; and the largest and most highly automated coal preparation plant of its kind-a plant ten stories high which washes, screens, and dries at the rate of 1500 tph, and produces both metallurgical and steam coal products. The Moss No. 3 preparation plant of Clinchfield Coal Co. Div. of Pittston Co. is located at Clinch- field, Va., only a short distance from the 450-tph Moss No. 2 plant, and was designed, built and erected by Link-Belt Co.

Jan 7, 1959