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By James D. Bliss, David M. Sutphin

"On the basis of differences derived from genetic, descriptive, and grade-tonnage data, graphite deposits are classified here into three deposit types: disseminated flake, amorphous (microcrystalline), or graphite veins. Descriptive models have been constructed for each of these deposit types, and grade-tonnage models are constructed for disseminated flake and amorphous deposit types. Grade and tonnage data are used also to construct grade-tonnage models that assist in predicting the size and grade of undiscovered graphite deposits. The median tonnage and carbon grade of disseminated flake deposits are 240 000 tonnes and 9% carbon and for amorphous deposits, 130 000 tonnes and 40% carbon. The differences in grade between disseminated flake and amorphous deposit types are statistically significant, whereas the differences in amount of contained carbon are not .IntroductionIndustrial minerals, including mineral construction materials such as sand, gravel, and crushed stone, have historically exceeded metals in global production value. Today, industrial minerals are being used in new and sophisticated ways in response to the late 1980s emerging information- and service-based economies' requirements for less metal and more industrial minerals . Natural graphite is an example of one such mine ral that has been known since ancient times, and is now finding new applications. Graphite was first used as an industrial mineral in Bavaria in 1400 A.D. where it was an important component of crucibles. Traditionally, natural graphite has been used in heavy industries. New applications, such as development of carbon-magnesite bricks a decade ago and the current advancement of alumina/graphite refractories, are increasing its graphite use. Other new uses for natural graphite, such as the use of graphite powder as a thermal blanket for the continuous casting o f steel (Northern Miner, 1987) and the addition of expanded graphite to polyurethane foam where it acts as a flame retardant (Industrial Minerals, 1987), are increasing the demand for this mineral. To meet future demand for graphite and other industrial minerals, knowledge of the characteristics of the deposit types in which they are found is important. A further look at the deposit types for graphite and at construction of descriptive and grade-tonnage models is warranted .The graphite industry recognizes three basic types of graphite , distinguished primarily on the basis of grain size: crystalline flake, lump and chip, and amorphous. These naturally occurring forms of graphite are products of metamorphism and are found in schists of various types, gneisses, and marbles. Temperatures of at [east 400°C are thought to be required for graphite formation (Landis, 1971). Synthetic graphite, also known as artificial or manufactured graphite, is a man-made carbon product and offers higher purity and lower crystallinity than natural graphite. Several authors have written about graphite's unique physical and chemical properties and the uses for individual types of graphite (Krauss et 01., 1988; Graffin, 1983; and Harben and Bate s, 1984)."

Jan 1, 1990

By Dale Preece, Stephen Chung

Development of DMCBLAST-3D is continuing and now includes the capability to simulate the detonation of multiple blastholes in multiple rows that make up a conventional bench blast, either in a rock quarry or a surface coal mine. DMCBLAST-3D is a three-dimensional extension of the proven twodimensional rock blast modeling code, DMCBLAST. DMCBLAST has been under development since 1987 and has successfully predicted the physics, mechanisms and results of a number of different types of rock blasting including, coal mine bench blasting, mineral mine choke blasting and underground stope blasting. Substantial effort has gone into the qualification and verification of DMCBLAST by comparing computer code predictions with real blasts in the field. Comparison with field data has also provided significant guidance to the development of the code.

Jan 1, 2002

By T. D. Yensen

EFFECT OF ELEMENTS ON MAGNETIC PROPERTIES OF IRON THE elements aluminum,1 arsenic,2 silicon,3 tin2 and vanadium,4,8 when used in relatively small amounts as alloying elements, seem to have a beneficial effect on the magnetic properties of iron-i. e., they increase the maximum permeability and decrease the coercive force-whereas there are definite indications that boron,5 carbon,6 nitrogen,7 oxygen,8' phosphorus,6 sulfur6 and titanium,4 as well as the metals of and adjacent to the ferro-magnetic group, nickel,9 cobalt,10 copper,11 and manganese,6 have a detrimental effect on these properties. The effects of calcium4 and magnesium4 are small, if any, while the effect of chromium 12 in small amounts is unknown and in large amounts is generally detrimental.

Jan 1, 1931

By Robin J. Hickson

El Abra is one of the world’s premier copper de-posits. The project is located in northern Chile, 140 km (87 miles) inland from the Pacific coast. It has the same geologic age and structural setting as the world-class Chuquicamata copper mine located 42 km (26 miles) to the south. The current development plan for El Abra extracts798 Mt (879 million st) of high-quality oxide ore. This will require building a solvent extraction/electrowinning(SX/EW) facility that can produce 225 kt/a (248,000stpy) of cathode copper. This will make El Abra the largest SX/EW copper operation in the world, and the world’s seventh-largest copper producer.

Jan 1, 1996

By Sup Hong

Herein, concept designs of two different types of mining robots are concerned, which are aimed for developments of deep seabed mineral resources: polymetallic nodules (PMN) and seabed massive sulfides (SMS), respectively. Continuous mining concepts are presented based on technical and environmental feasibility, where the environmental and functional differences for commercial productions are investigated. Needs and roles of versatile mining robots are explained as a key of continuous mining system. The functional requirements and design characteristics of mining robots to satisfy the top requirements from customers are described comparatively. Schemes of axiomatic design and quality function deployment (QFD) are utilized: functional requirements (FR) are defined, technical requirements (TR) are figured out, design parameters (DP) are derived, and degrees of importance of design parameters are evaluated. Analogy and discrepancy in remote operation methods are put side by side. A pilot scale mining robot for PMN and a commercial scale one for SMS are suggested in form of concept designs. PMN mining robot is shaped as a multiple configuration of unit robot modules in side dimension, in which the unit robot module consists of two tracks and two pick-up modules. SMS mining robot is based on a four-tracked vehicle. Main platform is mounted on the vehicle through turn-table. Excavation device consists of two-articulated boom and cutter tool. Crushing-and-pumping units are placed same in both robot platforms.

Jan 1, 2011

By R. W. Raymond

Under the names of Conservation, Social Justice, the New Nationalism, and Progressive Democracy, many earnest reformers are calling for a new system of Federal government to replace the one which they ascribe to our fathers, and declare to have been outgrown. They are proposing the lease by the United States of certain natural resources on the public domain, for the profit of the U. S. Treasury, instead of the sale of such resources to private citizens or associations of citizens. In the present paper, I shall try to show that this notion is neither new nor good. It is clear that the United States is owner, as well as sovereign, of public lands acquired through conquest or purchase from other nations, as it was owner of the public lands expressly ceded to it by the original thirteen States. Its policy with regard to such lands involves, therefore, two entirely distinct questions: What shall it do as owner ? and, What shall it do as sovereign ? The latter question, it must be confessed, has played but a small part in our history. All the prerogatives of sovereignty which were not explicitly conferred upon the Federal government by the original States were retained by them. The ownership or control of precious or other metals or minerals in the earth, for instance, was thus reserved to the several sovereign States. New York, South Carolina, and other States have passed laws on this subject, without regard to Federal authority. As new States have been successively admitted to the Union, the tacitly accepted theory has been, that they thereby acquired all the reserved rights of the original States. These newer States largely outnumber the first thirteen; and it is inconceivable that they would submit to any deprivation of sovereignty based on historical grounds. One of them—Texas—came into the Union by its own voluntary

Jan 1, 1913

By S. Blancher, A. Perroton, H Smith, T. Nzima, T. Wallmach, V. Dieudonné

Chromite beneficiation is generally performed by crushing and density separation using spirals. At the Dwarsrivier Chrome mine spiral efficiencies seam to vary, the reason for which is not evident. This sometimes results in the production of low-grade products, which are sold at relatively low prices. This paper represents a Qemscan® study that investigated mineralogical reasons for these variations. Variations in liberation of chromite particles as well as variations in chromite compositions were investigated. The results showed that the so-called low grade chromite product can be improved to become a high grade chromite product by means of a refinement in mineral processing. A detailed Qemscan® database (SIP file) was developed to account for variations in chromite chemistries. It can be shown that chemical variations with respect to Cr, Al, Mg and Fe in chromite particles reporting to the scavenger tails are larger than in the high grade product. A combination of these chemical variations together with a decrease in liberation of chromite particles in the scavenger tails can potentially help to recover more chromite particles from this specific process stream.

Sep 1, 2021

By Eckley B. Coxe

I WISH to call the attention of the Institute to a peculiar variety of anthracite which occurs in the Buck Mountain vein at our collieries at Drifton, and in the same and other veins in different localities in the anthracite coal-fields. It is known among the workmen as iron-gray or cast-iron. It has a dull, greasy appearance, as if a piece of ordinary anthracite had been rubbed with a dirty and greasy rag and allowed to dry. It was formerly considered a very impure coal containing a high percentage of ash, and was picked out of the coal and thrown away. But the following analysis of it and of its ash, made by Mr. J. Blodget Britton, of Philadelphia, shows that such is not the case, the percentage of ash not being much higher than that of the ordinary anthracites as they are prepared for market.

Jan 1, 1879

By J. C. Van de Water

In June the supply of M3 army demolition powder being used for mudcapping was depleted and we switched to 4 by 8, 60% Special Quarry Gelatin dynamite. This size cartridge has proved convenient, as a half stick will handle the average boulder. By keeping the gelatin in the paper while cutting it in two, there is little contact with the gelatin and therefore fewer headaches among the powdermen. To further help prevent the headache nuisance the men are furnished with plastic coated gloves. Boulder breaking costs as reported last year were $0.426 using M3. This year, 8180 boulders have been broken with M3 at a cost of $0.472 each and 7479 with 60% Quarry Gelatin at a cost of $0.660 each. This rise in cost is due entirely to the greater cost of the Gelatin as the method has not changed.

Jan 4, 1950

By H. Lyn Bourne

The is the 13th year for this column and the 12th in which the royalty data have been tabulated. There still exist some holes in the list of royalties that readers hopefully will fill. The most common mineral commodity is construction aggregates - either sand and gravel or crushed stone. In spite of their pervasive use nationwide, there are states from which the author has no information about royalties for either of these commodities. The reader can help - share information about these missing states and next year there will be fewer states without information. Severn Brown again sends helpful information from the Prospectors and Developers Association of Canada (PDAC). The PDAC Digest contained an article that distinguished between ‘net smelter return royalty' and ‘net profits royalty’ (Haase). The article also lists clauses and details that Brown suggests should be included in a net profits royalty contract.

Jan 1, 1994

1. COAL PRODUCTION: Under Section 402 of Public Law 95-87 (SMCRA), coal operators are required to pay a fee when coal is sold, used, or transferred. These fees are deposited in the U.S. treasury as the Abandoned Mine Land Fund. Information about the type of coal (bituminous, lignite, or underground) and tonnage are tabulated on Form OSM-1 and submitted with the fee, which is paid quarterly to the Office of Surface Mining. The coal production data presented in this report was compiled from information stored in the Office of Surface Mining Fee Collection System computer data base. Collection of the fee began with the last quarter of 1977; therefore, 1978 data includes the last quarter of 1977 and the first three quarters of 1978. Information for each successive year follows the same tabulation pattern. Surface production includes both bituminous and lignite coal; underground includes tonnage reported as underground mined. In New Mexico and Montana, coal production on Indian land is listed under the Crow, Hopi, and Navajo Tribes. 2. HISTORIC COAL PRODUCTION: Federal Government agencies have published coal production data since 1807, the date of the earliest record. The source of coal production data used to compile this graph was: 1891-1895, U.S. Geological Survey, Division of Mineral Resources; 1896-1977, U.S. Bureau of Mines annual Minerals Yearbook; 1978- 1991, Office of Surface Mining data described in footnote 1 above. 3. NUMBER OF MINES: The number of mines was compiled from Office of Surface Mining Fee Collection System data described in footnote 1 above. Annual totals were calculated by adding together the number of operations with the same Mine Safety and Health Administration numbers reported each quarter and dividing by four to give an annual number in each state. 4. ENFORCEMENT ACTIONS: Enforcement action data was compiled from annual reports developed by Office of Surface Mining field offices and historical field office records. The data presented are all actions taken by both the state regulatory authority and the Office of Surface Mining. Citations issued are the sum of Notice of Violations (NOVs) and Cessation Orders (COs). Because the Hopi and Navajo jurisdictions overlap in Arizona and New Mexico, enforcement actions data for the tribes have been combined in annual reports prepared by the Albuquerque Field Office; therefore, they are combined for this report and listed under Navajo Tribe. 5. ACREAGE PERMITTED: Acreage permitted data was compiled from annual reports developed by Office of Surface Mining field offices and historical field office records. The acreage listed was permitted during the year shown and is not the total acreage under permit during that year. 6. BONDS RELEASED: Acreage of reclamation bonds released was compiled from annual reports developed by Office of Surface Mining field offices and historical field office records. The sum of final Interim Regulatory Program bonds and Phase 111 (or final release) bonds shows only the land area where reclamation is complete and has been released by the regulatory authority.

Jan 1, 1992

By Xiaodong Jia, Richard A. Williams

"The packing of particles is a fundamental property of a material or system made up of particulates because it underlies many other physical properties of that material or system. Despite being ubiquitous, particle packing has not been an easy subject to study either experimentally or theoretically, except for a few regular shapes.This paper describes the recent developments, arising from research at Leeds, in the computer modelling of packing of complex shaped particles and prediction of physical properties of the structures represented by the packing. The computer model DigiPac, is capable of packing particles of any shapes and sizes in a container of arbitrary geometry. Figure 1 shows a few examples that are relevant to the mining and mineral industry.The ability to predict packing structure of real particle shapes and to compute directly some structuredependent physical properties (such as liquid permeability, mechanical strength/stability, compaction and sintering, dissolution and leaching, etc.) is obviously highly desirable and has significant potential in industrial applications. Examples are presented relating to the packing of granular materials.The mining and mineral engineering industries are well placed to exploit this advance in digital packing and simulation since they deal primarily with asymmetric and complex particulate mixtures. In the future we expect to see a number of developments in this area including:Algorithms that can optimise packing to achieve user-defined propertiesA more rational approach to determining flowability of complex powdersUse of these more realistic packing algorithms linked to blast and crusher design"

Jan 1, 2003

By William C. Hirt

Column flotation is a promising technique for processing as-mined, cobalt-rich, ferromanganese crust to separate the valuable crust component from barren substrate-rock, either aboard ship or within the water column. Column flotation testing was carried out in a seawater medium using samples obtained from the U.S. Exclusive Economic Zone (EEZ) in the mid-Pacific Ocean near Johnston Atoll. The collector reagent was a mixture of diesel fuel, fatty acid, and sulfonate previously developed at the U.S. Bureau of Mines for crust flotation using conventional flotation cells. Results are dependent upon particle size and reagent dosage, especially *as these factors affect froth volume and stability. Column flotation results are compared with previous studies in conventional cells. An overview of how column flotation might be applied in an offshore mining and processing system is given.

Jan 1, 1992

PRESIDENT MOSES: I think this will conclude our program for this afternoon, unless you have some- thing else. Mr. Holman, will you tell us what you are doing in the way of your local chapter, around Dawson? W. C. HOLMAN: (Chief Engineer, Phelps-Dodge Corporation, Dawson, New Mexico.) We have organized a local chapter of the Rocky Mountain Coal Mining Institute, and we invite all foremen, fire bosses, shot firers or anybody interested, either on the surface or in the mine. I think at the last meeting we had sixty to seventy men present. We hold meetings once a month; usually on a certain set Tuesday or second Friday of the month, or so on. We have a President, a Vice-President and a Secretary-Treasurer. There are no dues connected with it. We aim to take up the' papers that are presented at the various meetings of the Rocky Mountain Coal Mining Institute, and also any other subject that would be of interest, connected with our own mining operation. We usually ask two or three men to pre- sent papers, rather than one man. We find it difficult in getting one man to work up any subject, but two or three men work up very interesting papers. While we have just recently organized, we aim to have luncheons in connection with it, and possibly once a year a banquet or .some similar activity that we think would interest the men. We feel it is going to be a great help in carrying on the work of the present organization in presenting the activities around the mines. PRESIDENT MOSES: I thank you, Mr. Holman. Has any one any- thing to bring up at this time? MR. LITTLEJOHN: I would like to ask Mr. Holman if the Institute or the Chapter there is confined to Dawson alone, or open to other camps in New Mexico? MR. HOLMAN: At the present, Mr. Littlejohn, it is just confined to our own camp, although we intend to invite the members and the officials of the other camps later on, perhaps. Especially, if we gave a banquet, no doubt we would invite the others. MR. LITTLEJOHN: Is there any other Chapter in New Mexico besides yours in Dawson, Mr. Holman? MR. HOLMAN: None that I know of, right now.

Jan 1, 1926

By Johnston R. F

The factors which influence the reduction of chromite are investigated with special reference to Coobina chromite. This was compared with a South African chromite ore. The reduction characteristics are outlined and the reduction kinetics studied Temperature has the most significant effect, followed by particle size, silica addition and type of coal.Electron microprobe analysis of the products indicates that iron in the chromite is first reduced at temperatures above 1100°C, followed by chromium at around 1200°C. At temperatures greater than 1200°C metallic iron and chromium are formed simultaneously and subsequently give an iron-chromium-carbon alloy. It was observed that the metallic carbide contains a small amount of silicon. The decomposition of the chromite spinel was observed to pass through the FeO.Cr2O3, MgO.Cr2O3 and MgO.AI2O3 forms before slag formation. It is concluded that Coobina chromite is suitable for the production of ferrochrome if direct prereduction followed by intensive bath smelting is used.

Jan 1, 1994

This excellent paper by Dr. Colombo parallels quite closely the bench and pilot work done by the Hanna Research Laboratory on the Mesabi oxidized taconites. Because of the vast reserves and future ore requirements the need to perfect the selective flocculation-flotation process becomes very necessary. The selective flocculation process is a very efficient method of desliming, leaving a fairly clean, upgraded product for flotation. However, one of the problems that we have encountered in this process was some very fine, -2 micron liberated goethite in the slimes that did not flocculate. The complete slime removal is not necessary. We remove slimes to the extent of about 5% of the iron units. However, on difficult treating ores we would remove more slimes. The reclaimed water from our pilot plant has a turbidity of about 1000-3000 ppm. We can obtain lower turbidity water but to do this would involve additional lime as a tailing flocculant and we would run the risk of flocculating the entire ground pulp in the selective flocculation process because of the increased Ca level in the water. We have about seven different geological ore types out of 17 recognizable ore types that are treatable. All of these ore types require different degrees of dispersion and grinding which is a problem. The use of acrylic acid polymers as a selective flocculant has been patented by the American Cyanamid Co. This will-have to be

Jan 1, 1979

By Raymond E. Funderburk

Today, there are four alternatives available for disposal of highly toxic, non-radioactive hazardous waste: deep well injection, chemical processing, landfill and incineration. However, based upon research conducted by the author, a fifth alternative now exists. Disposal in salt. Salt, because of its chemical characteristics, is an ideal medium for retention of inorganic hazardous waste. Except for a few elemental compounds such as lithium and potassium, there is no reaction with sodium chloride. In the family of inorganic wastes, there are basically seven suites of waste that may be mixed together without any chemical reaction. The process developed by the author would be to take a suite of waste, either dewater or add moisture, add a solidification agent to the mix and slurry pipeline the mass into a cavern. Residence time before hardening can be adjusted, but the nominal time until full solidification is 48 hours. Once solidified, the mass will reach compressive strengths exceeding 3000 psi. The slurry can be introduced into an evacuated cavern pumped free of brine, or it can be placed beneath the brine and the waste will force the brine to the surface. The latter technique requires a high degree of engineering control to prevent contamination of the brine leaving the cavern-thus creating more hazardous waste and additional problems. The Environmental Protection Agency endorses the concept both at the research level and within EPA Headquarters. The technology will soon be utilized in a salt formation in Texas.

Jan 1, 1985

By Ernesto de la Torre, Karla Velín, Alicia Guevara

"The following study shows the improvement and simulation of a gold recovery plant of 24 t/day of capacity by gravity concentration, flotation and leaching. The ore processed had grades of 6 g/t Au, 15 g/t Ag, and 0.69 %Cu with the mineralogy consisting of 2 %chalcopyrite, 12 %pyrrhotite, 7 %plagioclase and 50 %quartz. The recovery process starts with crushing the ore followed by grinding it further in a ball mill. The ground ore is then concentrated in a Falcon centrifugal concentrator with concentrate being processed by amalgamation process. Gravity tails are sent to a flotation circuit where the copper minerals and some gold are concentrated. Lastly, the flotation tailings undergo cyanidation for gold recovery. Currently, the overall recoveries are 82.8 %Au, 49.6 %Ag and 99.1 % Cu. The optimization was developed in the laboratory using a Wilfley table by gravity concentration. Flotation tests in the laboratory were performed using potassium amyl xanthate and pine oil. Lastly, cyanidation was then performed on the flotation tailings. The results showed the optimum concentration of sodium cyanide in cyanidation is 2 g/L, which produced an increase in gold recovery from 30% to 44%. The reduction of diameter particle from 132 to 80 µm also produces an incremental recovery of gold and silver from 11% to 21% Au and 0.4 to 3% Ag in gravity concentration. Likewise in the cyanidation the recovery of gold and silver has shown a rise from 44 to 62% and 8 to 32% for Au and Ag respectively. However, the flotation method the gold recovery is reduced from 68 to 30% Au by reducing the particle size. Computer simulations using the programs, Moly-Cop and ModSim were performed to determine optimum parameters for the recovery of precious metals at the gold recovery plant."

Jan 1, 2014

By Donald O. Rausch, Robert H. Merrill

12.1 -1. Introduction. Problems concerning slopes in soils and rock generally arise in connection with road cuts and open pit mines. The angle at which a slope will safely stand is of major economic importance to both the road designer and the open pit operator. Stable slopes in soils and rock are evaluated through two fundamental approaches, namely, soil mechanics and rock mechanics. The approach selected to make this evaluation depends upon the material in the slope. For the purposes of this chapter, only slopes totally in soil or totally in rock are considered. By definition, soils are unconsolidated accumulations of solid materials produced by mechanical and chemical disintegration of rocks or the accumulation of sediments (28); rock is defined as the hard, compact, natural materials composing the crust of the earth (10). The basic factors affecting slopes in soil or rock are similar, although rock strengths are orders of magnitude greater than soil strengths. In general, the strength of large masses of soil depends upon the texture of the soil, the particle size, cohesion, and resistance to tensile and shear stress; the strength of large masses of rock depends upon the strength of the rock and the defects, such as faults, fractures or joints, that intersect the rock. Further, some of the defects in rock are cemented or uncemented, and may be filled with materials that are strong or weak compared to the rock. In slopes of either soils or rock, the stability is presumed to be a function of the slope height, slope angle, the size of the excavation, and the stresses imposed on the soil or rock by tectonic and/or gravity forces, earthquakes, or other static or dynamic forces. In addition, both soil and rock slopes are affected by static and dynamic water pressures in the pores of soils or permeable rocks or in the defects in the rock behind the slope. Visual observations of slope failures also indicate that both soil and rock can deteriorate with time, and this deterioration may be caused primarily by weathering (27).

Jan 1, 1968

Although copper production established a new record, lead and zinc registered gains, and iron production held steady, the mixed trend in metallic and nonmetallic mining and generally lower prices in 1961 resulted in a net decline in the total value of domestic mineral production. According to preliminary estimates from the U.S. Bureau of Mines, the value of metals produced in this country during the year was approximately $1.9 billion, a decrease of $117 million from 1960; the value of nonmetallics was about $3.7 billion, a $14 million decrease. The following report of mining and mineral developments during 1961 is based on USBM and industry sources. Aluminum Output Dips from 1960 Record Government reports indicate that the domestic primary aluminum industry produced approximately 1,880,000 tons, equivalent to 77% of this nation's capacity. This production is about 6% below the 1960 record output of 2,014,498 tons. Shipments of primary metal ingot slightly exceeded the quantity produced.

Jan 2, 1962