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By Walter Crafts

KEYNOTE of the technical sessions of the Iron and Steel Division at the Annual Meeting was struck by Leo F. Reinartz in his Howe Memorial Lecture on "The Development of Research and Quality Control in a Modern Steel Mill." In describing recent developments in steel-producing practices at the American Rolling Mill Co. the co-ordination of practical observation and directed research with operations was stressed and was shown to have resulted in economical production of steels of uniformly high quality. Empirical methods based on inaccurate and incomplete experience resulted in the production of commercial products of variable quality and were recognized as inadequate; a research program was therefore initiated that has been justified by its fruits. To name a few outstanding achievements such as Armco iron, steel for electrical sheets, wide continuous strip of superior surface and quality, and non-aging steel is not sufficient to summarize the results of this increasing effort toward better steel products. In addition to the development of new products the faithful observation of operating procedures, the co-ordination of the resulting information, and the standardization of processes have made the steel of today much more uniform and thus more economical and useful to the nation.

Jan 1, 1943

By Osvaldo Bascur, Barun Gorain, Jaco Steyn

"The last few decades have seen some remarkable advancement in information technology, but recently various digital technologies have resulted in several synergies to deliver innovation in diverse applications. The mining industry has been relatively slow in adopting these technologies compared to the other industries, but this scenario is changing fast.Challenges. Mining companies globally are going through a series of challenges such as declining ore grades with complex metallurgy, increasing depth of ore bodies, high capital and operating costs, lower productivity, shortage of technical resources, significant pressure from stake-holders to deliver, along with growing environmental and corporate social responsibility issues. Improvement in profitability would need significant improvements in operational performance.Consequently, over the last few years, there has been a major focus among some mining companies to imbibe operational excellence. This has been only possible because of the replacement of a silos-based approach by an integrated view of the organization. Such an integrated view is now possible via the evolving digital technologies. Even so, such a transformation calls for a change in culture, which, for most organizations is not trivial. Attempts in the past to integrate functions, such as through mine-to-mill initiatives in the mining industry, have demonstrated significant benefits to many operations (McKee, 2013). Still, sustaining these benefits has clearly been a challenge due to manpower turnover and lack of proper systems and structures that integrate information between business functions within an operation and between operations and the corporate level.Opportunities. The advent of digital technology has opened up opportunities to integrate interdepartmental information for a unified understanding across an entire organization. The advances in instrumentation, equipment control systems, supervisory control systems (SCADA/ Historian) and industrial networks have helped in the direction of enterprise- wide integration. The availability of real time information across an enterprise has given rise to numerous possibilities to improve organization performance. As suggested by Seshan and Gorain (2016), some of the potential opportunities are as follows:"

Jan 9, 2018

By B. Gorain

"INTRODUCTION The last few decades have seen some remarkable advancement in information technology, but recently various digital technologies have resulted in several synergies to deliver innovation in diverse applications. The mining industry has been relatively slow in adopting these technologies compared to the other industries, but this scenario is changing fast. Keywords: Digital Transformation, Operational Intelligence, Gold Recovery, Mine to Mill integration, Planning and Execution strategy, Theory of Constraints. Challenges Mining companies globally are going through a series of challenges such as declining ore grades with complex metallurgy, increasing depth of ore bodies, high capital and operating costs, lower productivity, shortage of technical resources, significant pressure from stake-holders to deliver, along with growing environmental and corporate social responsibility issues. Improvement in profitability would need significant improvements in operational performance. Consequently, over the last few years, there has been a major focus amongst some mining companies to imbibe Operational Excellence. This has been only possible because of the replacement of a silos based approach by an integrated view of the organization. Such an integrated view is now possible via the evolving digital technologies. Even so, such a transformation calls for a change in culture, which, for most organization is not trivial. Attempts in the past to integrate functions such as through Mine-to-Mill initiatives in the mining industry have demonstrated significant benefits to many operations (McKee, 2013). Still, sustaining these benefits has clearly been a challenge due to manpower turn over and lack of proper systems and structures that integrate information between business functions within an operation and between operations and the corporate.Opportunities The advent of digital technology has opened-up opportunities to integrate inter-departmental information for a unified understanding of, and across, an entire organization. The advances in instrumentation, equipment control systems, supervisory control systems (SCADA/Historian) and industrial networks have helped in the direction of enterprise wide integration. The availability of real time information across an enterprise has given rise to numerous possibilities to improve organization performance. As suggested by Seshan & Gorain (2016), some of the potential opportunities are as follows:"

Jan 1, 2018

By Lawrence Bragg

WE associate metals with hardness, toughness, and strength. But a curious paradox lies at the root of the valuable mechanical proper-ties of the metallic state: in order to be strong, a metal must be weak. This paradox, and the equally surprising fact that, in a sense, metals are not true solids at all, are among the topics here discussed by Sir Lawrence Bragg. (1) WHAT METALS MEAN TO US We employ various materials to build or fabricate the many objects we use in everyday life, choosing those whose properties are most suitable for the purpose which the object has to serve. Certain of these materials have been used from the earliest times, such as stone, wood, leather, and animal or vegetable fibres, each with its own peculiar valuable properties. Stone resists crushing and is very durable and permanent, as indeed it must be, since it has so long resisted change as a part of-the earth's crust. It is there-fore ideal for walls and buildings, and very early in his history man discovered how to make artificial stones by burning clay, with the advantage that they could be given any desired shape, and made into bricks or given elaborate forms as pottery. Wood is strong and tough and light, it resists tension as well as compression, and is nor brittle like stone. It forms beams and furniture and parts of tools or weapons. Leather is tough but at the same time iris flexible; it is ideal as straps or sheers. Vegetable fibres such as linen or cotton, and animal fibres such as wool and silk, owe their value to their flexibility and strength in resisting extension. They can be spun into yarn or rope, and woven into cloth. The technological age in which we are now living is replacing the natural products used by early man by a series of artificial products, but it is remarkable to see how in nearly every case we are copying Nature's materials. The wide use of concrete represents a developed art of making artificial stone. Artificial fibres such as rayon or ?nylon replace cotton, wool, and flax. Plastics are coming very much to the fore; they correspond to early man's use of horn, another substance with peculiar properties of roughness in all directions without the 'grain' of wood. For the most part we are following in the footsteps of our remote ancestors, though we can make for ourselves what they had to cull from wood and field. There are exceptions; for instance, we have discovered comparatively recently the number of uses to which natural rubber can be put, and are now making it artificially. This is a really new discovery; our ancestors had nothing with such remarkable powers of elastic stretching without breaking, and resistance to being abraded.

Jan 1, 1943

By Cyril Stanley Smith

ARCHEOLOGISTS, by use of the terms Bronze Age and Iron Age, indicate that metals have in the past determined the character of civilization. The relatively simple discovery by a primitive metallurgist that the addition of tin to copper both facilitated the production of castings and increased the durability of the product enabled hunter, warrior, and housewife alike to do things never dreamed of before. Similarly, the smelting of iron and the discovery of hardening methods greatly changed the arts of peace and war. Discoveries of low-melting-point alloys for joining and for making household utensils, and perhaps the adornment of a feminine form by sparkling precious-metal jewelry, have at times changed the destiny of a country. Bronze cannon, the cast and wrought iron Watt engine, copper transmission lines, and aluminum alloy aircraft, are cases of particular metals making possible the realization of an improved engineering design. Perhaps of the greatest influence of all upon civilization was the development of type metal. The rapid increase in the rate of dissemination of knowledge dates from the day that the technique of the pewterer was utilized in making rapidly reproducible and accurately sized letters for printing. It was not movable type, but metal type that was important, for metal castings could be made of identically the same shape and size at an enormous rate, and possessed excellent inking and wearing characteristics.

Jan 1, 1946

By C. H. Mathewson

MY treatment of the subject of "Metals of the Future" is imaginative rather than statistical or scientific, because reliable information concerning useful concentrations in the form of ore deposits of by far the majority of the elements does not exist and the chemical, physical, and mechanical properties of the unfamiliar metals are recorded only in fragmentary and uncertain form or not at all.

Jan 1, 1944

By Maurice Deul

This bulletin summarizes the work conducted under the Bureau of Mines methane control research program during the years 1964 to 1979. This research effort was directed toward improving existing methods and developing alternative methods of reducing the explosion hazard during mining. The research was performed in three general areas: (1) basic factors that control the emission of methane into coal mines, (2) methane control during mining, and (3) methane drainage in advance of mining. Topics discussed in this bulletin include the magnitude of the methane problem; the equipment and instruments developed; the geological, chemical and physical parameters that control the movement of methane in coalbeds; the direct method of determining gas content; the estimates of gas content from adsorption data; and methane drainage, through shafts, through horizontal boreholes, through vertical boreholes, or through slant holes. Improvements in ventilation, control of methane in gob areas, and water infusion are also discussed, as is the potential use of coalbed methane as a supplement to natural gas supplies. This bulletin provides a comprehensive source of information on the accomplishments of the Bureau's methane control research program, on the technology developed, and on the direction of further research.

Jan 1, 1986

By G. W. McMahon

Following the Sago Mine accident, the U.S. Mine Safety and Health Administration (MSHA) asked the U.S. Army Engineer Research and Development Center to study several possible methane explosion scenarios in the Sago coal mine. The study used a 0.3-m (1-ft) resolution map of the mine to produce a 3-dimensional (3 D) model of a portion of the mine, including the sealed area where the explosion occurred. An advanced 3 D computational fluid dynamics (CFD) code was used to calculate the explosion pressures within the sealed area, on the mine seals and in nearby regions of the mine. Based on the best available information on methane concentrations and assumptions on homogeneity and on layering and mix composition, three separate initial conditions of methane-air concentrations and location were studied. This paper discusses the CFD modeling technique, the results of the calculations, the challenges of conducting this type of modeling and the advantages and limitations of CFD modeling of accident investigations of mine explosions.

Jul 1, 2010

By A. Z. Dimitroff

Immediate detection of methane buildup or of sudden liberation of large quantities of methane in the face area is essential to avert disasters in coal mines. Proper timely detection and handling of methane have always presented problems in extremely gassy mines, and these problems have been magnified by present accelerated mining methods. Strict rules and regulations have been established by coal-mining companies, States, and the Federal Government, which provide for periodic inspections for methane in face areas when electrical equipment is working. Other provisions require the operator' to shut down electrical face equipment and change or adjust ventilation when more than 1.0 percent of methane is detected. Nevertheless, human failure to detect such conditions has been responsible for numerous ignitions arid explosions Recognizing this fact, Marling J. Ankeny, former Director of the Bureau of Mines, proposed in 1958 the development of an automatic methane-monitoring device. He envisioned such a device as being entirely dependable, capable of giving a warning when a predetermined concentration of methane in air is reached, and capable of deenergizing the equipment and rendering it inoperative when a dangerous concentration of methane is present in the air. Such a device has been developed by the Bureau of Mines Health and Safety Research and Testing Center in Pittsburgh, Pa.

Jan 1, 1967

By BruneJurgen F., Richard C. Gilmore, Matthew Schreiner, Ray Johnson

Explosive pockets of methane-air mixtures accumulate in underground coal mines and, when ignited, produce an air-blast wave that can disturb combustible coal dust on the floor, roof, and ribs. To prevent explosions, the coal dust must be continuously diluted through application of inert rock dust, usually powdered limestone. Application of powdered dust process creates a respiratory nuisance downwind, where miners cannot work until the dust settles. Rock dust suppliers have developed wet and foam applied products to reduce the nuisance and limit the interruption to mining during dust application. To test the effectiveness of these alternative dust products, researchers at the Colorado School of Mines (Mines) have constructed a full-scale explosion test drift located at the Mines Edgar Experimental Mine (Edgar) to study the dispersibility of different rock dust applications. This paper examines the use of Pentaerythritol tetranitrate (PETN) detonating cord to produce controlled air-blasts that simulate methane-air explosions. The air blasts are generated with curtains of detonating cord that produce shockwaves with wind speeds between 30 to 70 m/s (100 to 225 fps) depending on the length of 5.3 g/m (25 grain/ft) detonating cord used. These velocities represent the minimum air speeds required to trigger propagating coal dust explosions. Researchers have conducted 40 test blasts with various lengths of detonating cord. Results show the two primary waves and two reflected waves each decaying into airblast waves with overpressures of 14 to 27 kPa (2 to 4 psi). Pressures were recorded with commercial piezoelectric transducers and custom-built, bi-directional probes to record the total and dynamic pressures of the wind generated in the explosion. Researchers were able to generate consistent and repeatable wind speeds and air-blast durations sufficiently similar to a methane-air explosion to study the dispersibility of various rock dust products and application methods

Jan 1, 2019

By J. Shen

Direct methanol fuel cells have been the subject of considerable research in the last decade. Performance levels realized in cells, stacks, and systems show that this technology is a promising power source for a wide range of portable applications. A direct methanol fuel cell (DMFC) operates directly on a methanol fuel stream typically supplied as a methanol/water vapour or as an aqueous methanol solution in liquid feed DMFCs. The fuel streams in DMFCs are usually recirculated in order to remove carbon dioxide and to re-use the diluent and any unreacted fuel in the depleted fuel stream exiting the DMFC. The concentration of methanol in the fuel circulation loop is an important operating parameter because it determines the electrical performance and efficiency of the direct methanol fuel cell system. The methanol concentration in the circulating fuel stream is usually measured continuously with a suitable sensor, and fresh methanol is admitted in accordance with the signal from the sensor. There are many factors to consider in developing a methanol sensor suitable for DMFCs. These factors include sensitivity, cost, size, simplicity, reliability, longevity, concentration range, and dynamic response. In particular, reliability and low cost should be addressed. Methanol concentration sensors measure methanol concentration by means of detecting the variations of physical/chemical properties of the solution. In this work, methanol concentration sensors based on electrochemistry, electric-capacitance measurement, infrared sensing, ultrasound sensing, and other techniques are reviewed to discuss their advantages and disadvantages.

Jan 1, 2005

By R. E. Miller

Hoisting coal using water and air is a technology which has potential to improve the economics and safety of transporting coal. The Coal Air-Lift Hydrohoist is a prototype coal hoisting system developed by the U.S. Bureau of Mines (USBM). This paper discusses the method used to regulate the supply of water to the 50-m-high hydrohoist U-tube such that the pressure difference at the bottom of the U-tube is held constant. Maintaining a constant pressure difference results in a steady flow of slurry out of the hydrohoist.

Jan 1, 1995

By G. R. Fitterer

NONMETALLIC inclusions in steel have received much attention by metallurgists during the past few years. Many investigators have been emphatic in stating their belief that these impurities are the chief causes of steel failures, while others think that their effects are negligible. One of the main reasons that definite information on the effects of these impurities is lacking is that no reliable method has been developed for the exact determination of the amounts of these different impurities in steel. Some valuable new information has been brought out by a reliable method for nonmetallic inclusions which has been developed at the Pittsburgh Experiment Station of the U. S. Bureau of Mines, in cooperation with the Carnegie Institute of Technology and the Metallurgical Advisory Board. This procedure satisfactorily extracts some of the more common inclusions from steels, thus enabling the investigator to correlate steel failures with inclusion content. Although the data given herein are the first to be published on the subject of the electrolytic extraction method, the interest in the subject is evidenced by the fact that it is already being used by some 20 to 30 steel companies for their various purposes. Some of the comments received from these laboratories indicate that the method is highly satisfactory: the unfavorable comments, when traced to their sources, have been found to be based on some small mistake made in either installation or operation. The chief discrepancy seems to have occurred in attempts to apply the method to the extraction of inclusions from alloy steels. The procedure can be used only for the plain carbon steels and for such low alloy steels as those containing the usual amount of copper (0.2 to 0.3 per cent). Steels containing the carbide-forming alloys such as chromium, tungsten, etc., present far too many difficulties for the accurate determination of inclusions. Luckily, the iron and manganese carbides do not offer any difficulties and no contamination of the oxide-sulfide residue results. It is highly probable that some modification of the following

Jan 1, 1931

By F. R. Hewitt

THE methods of mining talc are simple, and in western North Carolina are almost entirely by open cut and quarry. The larger part of the talc of this section lies in various-sized "veins" inclosed in quartzitic walls, the majority of which have by folding been thrown into a perpendicular position, or nearly so, and the exposed edges of which have been covered by debris from erosion of the mountain above. This covering of loose rocks and earth is from 5 to 25 ft. thick, and in most cases has to be removed because it is difficult to support. Sometimes the covering is heavy enough to "catch" and timber successfully, and in this case the talc can be worked out by the usual method of following the "vein," using stulls for holding up the walls until the vein is worked out, and then allowing the cut or drift to fall in. In some cases it proves more convenient to sink shafts and run drifts, following the talc "veins" until exhausted. The talc deposits of this section are badly broken and faulted both laterally and perpendicularly, and in some cases are found many feet below the level of drainage, necessitating pumping at considerable expense. . My own experience in mining talc has been that the chief point is to get a reliable "vein," and that then the mining is not as difficult, or any more so at least, than that of any common ore. If the. "veins" are pure talc it is simple; if the talc is admixed with foreign matter, such as tremolite in excess, or stains of iron or manganese, as is often the case, one had better abandon the deposit.

Jan 8, 1916

As has been the case since the early Phoenician traders, the minerals used by modern man come from deposits scattered around the globe. The price received is more and more being set by worldwide supply and demand. Thus the price component in the profit equation:Profits = Material sold (units)x(Price/unit û Cost/unit) is largely determined by others. The recent price history for two of the major metals, copper and iron, are given in Figures 1 and 2, respectively. As can be seen there has been a steady decline in the prices (when expressed in constant dollars) over the 20 years which have lapsed since the first of the International Conferences on Mass Mining, æDesign and Operation of Caving and Sublevel Stoping MinesÆ was held. If one would look back over the entire 20th century this would also be the trend. Cost containment/reduction through efficient, safe and environmentally responsive mining practices is serious business today and will be even more important in the future with increasing mining depths and more stringent regulations. A failure to keep up is expressed very simply as: Profit This, needless to say, is unfavourable for all concerned (the employees, the company, and the country or nation). The mining companies have had to look at ways of reducing the expense part of the profit equation while maintaining safe, environmentally conscious operations. Table 1 summarises the rules for working in todayÆs economy.

Jan 1, 2000

By L Scheunis, A Van den Bulck, E Jak, K Verbeken, M Shevchenko, R Starykh, I Bellemans, P-J Boeykens

As a result of the globally increasing consumer use of electronic devices, it is expected that pressure will increase on the supply chain of precious metals. Hence, recycling of these electronics becomes increasingly important, as well as optimising the current processes. One major issue in metallurgical processes is the amount of metal that is lost into the slag. This metal loss is inherent to the production process and therefore, additional processing steps such as slag cleaning may be required. Slag cleaning can be done in electrical resistance furnaces where heat is produced using the Joule effect, making the slag’s electrical conductivity an important operating parameter. Since slags are ionic liquids, the electrical conduction happens via the movement of ions which is called ionic conductivity. However, within the presence of transition metal oxides, a second mechanism of conductivity occurs as electrons are able to hop from one transition state to another, which is known as electronic conductivity. As ‘FeO’ is a common slag component in the non-ferrous pyrometallurgical industry, both mechanisms are present, but their proportions vary with the respective amounts of the two forms of the multi-valent ions and hence, with the oxygen partial pressure. The goal of the present study is to develop an experimental set-up and methodology for measuring the electrical conductivity of synthetic SiO2 – CaO – AlO1.5 – ‘FeO’ slags at various oxygen partial pressures.

Jun 19, 2024

By J. Sepulveda

"Despite the recognized influence of product fineness on line capacity and downstream process performance, few mineral concentrators today use particle size measurement of the final product in automatic control applications for particle size. ‘Near-line’ particle size instrumentation has existed for decades and is utilized in modern concentrators, but low availability and measurement frequency, due to problems with slurry sampling and transport systems, make these technologies unreliable for use in automatic control. An innovative technology for real-time particle size measurement on individual hydrocyclones, named CYCLONEtrac™ PST (particle size tracking), has been developed by CiDRA Minerals Processing, and proven in commercial installations, demonstrating near 100% availability with minimal maintenance requirements, thus overcoming the limitations of previous technologies. Potential stakeholders require convincing, reliable information regarding the economic value delivered by automatic grind control projects. In this paper we present a methodology for estimating such value with the CYCLONEtrac™ PST technology, and demonstrate unique opportunities to improve process stability and performance. Based on actual plant data accumulated over time, the evaluation approach assesses and highlights the significant potential process improvement that can be expected with the particle size tracking technology. As an extension of previous work, in this paper we present the key operating criteria for optimizing the production of valuable metals and increase mill throughput by identifying the optimal grind size. As this requires operating closer to the process boundaries, accurate real-time particle size measurements, such as those provided by the CYCLONEtrac™ PST system, become essential for achieving the maximum potential value from every operation. For further illustration, data from three different copper plants is compared.Introduction Owners and operators of mineral concentrators constantly search for the most economically attractive way to increase the output of valuable metal. A logical approach is to identify a key parameter that has the greatest impact on the performance of multiple stages of the process and then use a holistic analysis methodology to determine how this key parameter can be controlled to optimize the final output.Particle size is widely recognized as such a key parameter; however, very few concentrators today use real-time particle size measurements for automatic control of the final product size due, to a large extent, to the inherent limitations of existing technologies. ‘Near-line’ particle size measurement instrumentation, which has been used for decades, typically suffers from low availability because the fundamental measurement technologies were developed for other, less demanding industries and then adapted to the harsh environment of the typical mineral concentration process. An outline of the key differences among the available technologies used for particle size measurement in comminution circuits has been completed in previous work, and plant data has proven the benefits of measurements on individual cyclones – something that, until now, has not been possible (Cirulis, 2017)."

Nov 1, 2018

By K. L. Azinger

Successful relationships between mining companies and local stakeholders are now an essential part of the social contract of “doing business” (Prescott, 1995). The methodology presented in this paper is designed to assist mining companies in understanding and building relationships with diverse stakeholder groups. The methodology starts by recognizing that mining projects have a natural life cycle which can be used to identify when new external affairs strategies are required. In designing an external affairs strategy, the first step is to set objectives that are compatible with the overall objectives of the mining project. The management team then identifies the main stakeholder groups and seeks to understand the priorities and inter-relationships of the individual stakeholders. The result of this stakeholder analysis is an understanding of the Degrees of Influence of each of the stakeholder groups along with a relationship map which illustrates the strong interactions between stakeholders. The company is then prepared to take a proactive approach to building relationships with the primary stakeholders. This methodology was developed by BHP to assist with the federal government environmental approval process for the development of Canada’s first diamond mine. BHP has successfully used the methodology in three different phases of the NWT Diamonds Project and is now applying the methodology to mining and development projects around the world.

Jan 1, 1998

By J. M. Mutmansky

"The objective of this study was to produce coal dusts for laboratory research that are similar to mine airborne dusts in chemical, mineral, and physical characteristics. In this investigation, dusts produced in laboratory comminution equipment were compared with continuous miner- generated dust for similarity in physical characteristics. Mining-generated dust (MGD) and bulk coal samples were first collected from an underground mining operation. The bulk samples were then processed in the laboratory for size reduction in various comminution devices. These laboratory- generated dust (LGD) samples were subjected to size and microscopic analyses. Physical properties of the dust particles were studied on a scanning electron microscope (SEM ). A numerical shape coordinate system (SCS) was also developed and applied to 300 particles from each sample. Statistical analysis was then performed on the collected data and characteristics of the MGD and LGD samples were compared. IntroductionIn many biomedical studies, researchers routinely introduce a dust mass into an experimental environment to assess the response of a biological entity, usually lung macrophages in vitro or a live laboratory animal, to the dust mass. To provide data of maximum usefulness, it is highly desirable to use dust with characteristics of actual mine airborne dust. The primary objective of this research was to produce dusts in the laboratory similar in chemical, mineralogical, and physical characteristics to mine airborne dusts. This paper outlines the evaluation of the physical characteristics of the lab-generated dusts.Particle shape analysis is perhaps the least-developed area in mineral-related particle science and technology. There are still no standard methods or instruments to scientifically quantify particle shapes. To date, many attempts have been made to characterize particle shapes. These procedures can be roughly classified into three categories:"

Dec 1, 1995

By George Saratsis, George Exadaktylos

In the marbel industry, ore reserves refer to the produced tonnage of orthogonal prismatic, defect-free blocks of commercial sizes and of marketable aesthetical quality. On the contrary, in the mining sector, ore reserves refer to the tonnage of ore with grade above some cut-off value. While in the mining sector ore reserves are reported according to existing standard guidelines, the marble industry has no standardmethod. The purpose of this paper is to present a method to estimate white marble reserves using drill coring or borehole wall logging and limited joint mapping on exposed marble surfaces. Data pertaining to fracture orientation, fracture frequency, size, and whiteness were collected. The primary phase of marble characterization is followed by the discretization of the orebody into a three-dimensional array of orthogonal prismatic blocks, where the marble whiteness and fracture intensity are attribute values. Both these variables are considered to obey continuous and not discrete probability distributions. The discretization is performed using computer aided design and the Block Kriging techniques. An outline to improve the description of a given marble ore deposit at the exploration stage is presented for the prediction of marble block size distribution from joint count measurements along diamond drill cores. An example case of a white dolomitic marble quarry is used to demonstrate these methods.

May 27, 2020