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Mine production planning and scheduling as a production planning problem can be handled using Linear (Goal) Programming. This approach is particularly useful when the product quality is important. This has been shown for many mine planning cas

Jan 1, 1998

By Aitchison J, Clarke G

A reappraisal of the stratigraphy, new regional kinematic analysis and thermobarometric data allow a new interpretation of the metamorphic zoning and tectonic structure of the Upper Eocene high-pressure metamorphic core complex of northern New Caledonia allow a three steps evolution to be proposed : 1) subduction and understacking of previously thinned continental crust elements; 2) subduction blocking due to the crustal thickening; 3) crustal thinning and extensional detachment during the diapir-like uplift and unroofing of the eclogitic core. Steps 2 and 3 may be partly contemporaneous. Such a model accounts for the thermobarometric and radiochronologic data, and also for the weakness of substratum deformation during the emplacement of the ophiolitic nappe.

Jan 1, 1995

Dynamic permeability is a significant hydrologic condition associated with in-situ leaching at the Cyprus Casa Grande operations. Several factors contribute to changes in the permeability conditions. They are: 1) hydraulically induced fracture development, 2) geochemical changes during leaching in the rock matrix, and 3) changes in the relative degree of saturation of the deposit. Dynamic permeability conditions were evaluated using available pressure and flow rates from the 58 injection and recovery wells obtained over one year period. A finite element, 2-D hydrologic model called INVERT which is designed to estimate aquifer parameters under transient and steady state flow conditions was used for the investigation. The permeability conditions during 7 different steady state intervals throughout the one year time frame were determined. The results confirm that big changes in permeability occur as a function of time as well as a function of injection pressure condition.

Jan 1, 1991

By Anna Carolina Cerqueira Neves

Synthetic fiber has been gradually replaced by natural fiber, such as lignocellulosic fiber. In comparison with synthetic fiber, natural fiber has shown economic and environmental advantages. The natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. However, until now little has been evaluated about the hemp fiber incorporated in polymeric matrices. This study has the purpose of evaluate the impact resistance of this kind of epoxy matrix composite reinforced with different percentages of hemp fibers. The impact resistance has substantially increased the relative amount of hemp fiber incorporated as reinforcement in the composite. This performance was associated with the difficulty of rupture imposed by the fibers resulting from the interaction of hemp fiber / epoxy matrix that helps absorb the impact energy.

Aug 16, 2017

By J. E. Kogel

Industrial minerals play a central and dual role in the sustainable development (SD) of natural resources. Over the past decade the mining industry has increasingly focused on sustainably extracting and processing industrial minerals. This trend has been driven by higher energy costs, diminishing water resources and sensitivity towards environmental stewardship. Industrial minerals have been used throughout human history as low cost, naturally occurring, materials. Today they are critical components of recycled packaging, energy efficient building materials, light weight paper coatings, and other products critical to the responsible utilization of global resources. As industrial minerals become more widely used in ?green? products, mining companies have established best practices for the sustainable management of industrial minerals mining and processing. These management practices include reducing energy consumption, minimizing water usage, increasing waste recovery through recycling and process optimization, and maximizing the amount of ore extracted per acre of disturbed land. With the commitment to SD principles, quantitative methods for objectively measuring SD performance have become increasingly important. Measuring sustainability impact is a valuable tool for effectively applying SD principles and for making choices that balance sustainable development against other business objectives. SUSTAINABLE DEVELOPMENT AND MINING Sustainable development is a term that has become a common part of our lexicon; however, it has multiple meanings and interpretations leading to a sometimes confusing and contradictory array of definitions. The absence of a single, precise definition reflects the fact that SD is a broad concept or paradigm that offers guiding principles as opposed to a specific set of criteria or regulations enforceable by government or other oversight agencies. While a principle based conceptual approach allows businesses to broadly apply SD practices that are tailored to their specific situation, it has also led the public to sometimes view voluntary corporate SD programs with a degree of skepticism (Walker and Howard 2002). This is particularly true in the mining industry. One reason for this skepticism is that the relationship between SD and mining is misunderstood and to many, sustainably developing non-renewable mineral resources is a contradiction (Rajaram et al. 2005). However, this view takes a very narrow interpretation of the tenets of SD. The second is that mining carries a legacy of poor environmental stewardship that does not accurately reflect current corporate environmental practices Many minerals companies have adopted the Brundtland Comission?s definition of SD (United Nations 1987): ?? development that meets the needs of the present without compromising the ability of future generations to meet their own needs?. This definition is very broad and can be interpreted in a number of ways. It provides a general context for sustainable development and is not intended to provide detailed guidelines addressing specific aspects of sustainable development. To fill this gap the following SD principles were drafted by the international minerals community in 2003 (ICMM 2003): 1. Implement and maintain ethical business practices and sound systems of corporate governance. 2. Integrate sustainable development considerations within the corporate decision-making process. 3. Uphold fundamental human rights and respect cultures, customs and values in dealings with employees and others who are affected by our activities. 4. Implement risk management strategies based on valid data and sound science. 5. Seek continual improvement of our health and safety performance. 6. Seek continual improvement of our environmental performance. 7. Contribute to conservation of biodiversity and integrated approaches to land use planning. 8. Facilitate and encourage responsible product design, use, re-use, recycling and disposal of our products. 9. Contribute to the social, economic and institutional development of the communities in which we operate. 10. Implement effective and transparent engagement, communication and independently verified reporting arrangements with our stakeholders. These guidelines insure that SD concepts are applied equally across the industry while setting a clear performance standard and benchmark against which to evaluate success. By adopting these principles and issuing the Milos Statement (http://www.sdimi.org/milos_decl_October%206_2003.pdf), which provides a more detailed vision for integrating SD into everyday business operations, the minerals industry has embraced SD as a core corporate value. The unifying and holistic approach embodied in SD principles impacts the entire mine to market life cycle and addresses the economic, environmental and social consequences of mining. INDUSTRIAL MINERALS The world economy relies heavily on minerals; they are essential to economic prosperity and the quality of life. Industrial minerals are non-metallic, non-fuel minerals that provide the raw materials for a vast range of products used in most every aspect of daily life. They are mined and processed worldwide and they span the spectrum from relatively low value, high volume commodities (e.g. common clay, crushed stone) that are usually mined locally to high value, low volume specialty materials that are sourced from unique one of a kind deposits (e.g. barite, talc, mica). High volume commodity mining operations are often located near the end use market which, in most cases, means areas of high population density where construction and other urban activities drive demand. In these situations the strict adherence to SD principles is particularly critical as these are highly visible operations that must meet the public?s demand for good corporate citizenship. These operations are similar to chemical or other manufacturing facilities that operate near population centers. In contrast, some mining operations are located in remote but environmentally sensitive regions of the globe where the pressure to mine sustainably is driven by the need to preserve habitats and other

Jan 1, 2009

By James Withers, Dongbo An, Jinhong Zhang

A micro-scale investigation was carried out by applying an atomic force microscope (AFM) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to study in situ the adsorption of three different collectors — oleic acid, octanohydroxamic acid (HA) and salicylhydroxamic acid (SHA) — on bastnaesite in aqueous solutions. The results show that all three collectors adsorb on bastnaesite. The hydroxamic acid collectors — HA and SHA — adsorb on bastnaesite mainly in the form of insoluble metal hydroxamate. Their specific adsorption mechanism indicates that high selectivity will be achieved with a hydroxamic acid collector for the flotation of bastnaesite.

By A Gibbs

Culture and leadership go hand in hand, especially when it comes to investing in safety. But the reality is that most safety leaders haven’t been taught the fundamental soft skills needed to lead effectively. In fact, only one in four safety leaders demonstrate effective skills and behaviours. Furthermore, when compared to its peers in other high-risk industries, our research indicates mining has the most room for improvement when it comes to effective safety leadership. In this presentation safety culture, climate and leadership will be outlined. Additionally, research data collected from our clients, across a variety of industries, will be shared to inspire reflection on the value of safety leadership. Finally, strategies to empower leaders and increase safety leadership behaviours will be described.

May 5, 2022

By E. R. DeMen

In late 1965 General Mills announced the availability of a new liquid ion exchange reagent, LIX®-64, for the recovery of copper from various solutions, such as dump leach liquors. Acceptance of this material by the copper industry has been gratifying. A number of pilot plants have been operated, and at this writing there are four commercial plants either in operation or under construction. The properties and operating characteristics of this reagent have been described in previous papers.1,2 LIX-64 is quite effective and selective for copper extractions although partially limited in pH ranges, losing extraction efficiency as the acidity of the feed solution increases to below pH 1.0. Also, the LIX-64 content in the kerosine carrier was limited to about 10 volume percent (except for special cases) because of rapidly decreasing phase disengagement rates above this content. This in turn led to large plant capital costs, as the organic flow rates had to be in- creased (rather than LIX-64 content) to extract the copper from high content liquors. This was true in all circuits where the feed copper content ran above 2.0 g/l copper. A reagent was needed which would extract copper from more acidic liquors (or higher copper content liquors) and which exhibited improved phase disengagement characteristics with reagent contents up to 30 volume percent. General Mills is pleased to announce the availability in commercial quantities of a new and improved reagent, L+-64~. This reagent broadens the pH range in which copper can be extracted, and exhibits superior phase disengagement characteristics. The improvement in the reagent has been noted in laboratory circuits, as well as pilot plant runs and commercial operations.

Jan 1, 1970

By A. P. Cohen, D. W. Fuerstenau

Methods of accounting for the feed size in analyzing the size distribution shift during comminution have been discussed in a number of papers.1,2,3 Based on experiments which charles2 performed with single Pyrex specimens, Schuhmann4 pointed out that the size modulus of an assembly of particles should be determined by the energy expended per unit volume (or mass), independent of the size of particle being comminuted. In this same paper, Schuhmann derived the Charles energy-size reduction relationship by considering that complex comminution operations can be considered to be the summation of many individual comminution events, each of which must be governed by Were 6wi is the mass of a particle receiving the impact, 6Ei is the energy delivered to the particle, ki is the size modulus of the product resulting from the impact, a is the distribution modulus of the assembly of particles, and A is a constant. Recent experiments on the compression loading of Pyrex spheres ranging in size from 1/8 to l-in. diam have shown that the size modulus of the fragments is determined by the strain energy at fracture per unit mass, independent of sphere diameter.' The objective of the present investigation has been to determine experimentally whether the size distribution of the product from such a complex comminution process as rod milling is determined only by the energy expended per unit mass independent of feed size. Samples of each Tyler sieve fraction ranging from 4x6 to 48x65 mesh were prepared from crushed Brazilian quartz crystals. One kilogram of each fraction was ground at 60 pct solids in an 8x9 1/4-in. mill containing 17.5 kg of rods (26 rods, 5/8-in.; 10 rods, 3/4-in.; and 5 rods, 7/8-in. diam). In each test, the mill was run at 77 rpm for 15 min. Size distributions were determined by a wet-dry sieving technique. Table I presents the size distribution of the products obtained by grinding each of the size fractions. Because the size distributions are so nearly alike, they are plotted in Fig. 1 by shifting each size distribution for the different feed sizes one screen fraction to the right. Thus, the lowest point in each size distribution represents 400 mesh and each of the other sieve sizes must be shifted accordingly. A single regression line was calculated by combining the data for the six tests, excluding the coarsest feed and the two finest feed fractions. 6 This regression line, which is given by (Y \0.88 where y is the cumulative percentage of material

Jan 1, 1962

By Sugui Tian

By means of the T6 treatment, the measurement of creep curves and microstructure observation, the influence of T6 heat treatment on the microstructure and creep properties of Ti-6Al-4V alloy is investigated. Results show that the microstructure of the forged alloy consists of the banded-like a phase and networks b phase. After sub-temperture T6 treated, the microstructure of alloy consist of the block a phase and ?networks basket? structure. Under the conditions of the applied stress of 575 MPa at 4000C, the forged alloy displays a lower creep lifetimes, after T6 treated the creep lifetimes of the alloy is enhanced to 548 h from 66 h, which is attributed to the formation of the network basket structure in which the needle-like phase are dispersedly distributed. As creep goes on, the denser dislocations in the a phase are concentrated to occur the dynamic recrystallization for refining grain. which is a main reason of the alloy displaying a better creep lifetimes and plasticity. Thereinto, the creep mechanism of the forged alloy is thought to be the slip of the straight <a> and <a+c> dislocation are activated on the prismatic planes and pyramidal planes, while the creep mechanism of T6 treated alloy is that wave-like <a+c> dislocations are activated on the pyramidal planes.

Jan 1, 2009

By O. Bazhko, F. D. L. Uahengo, Y. R. S. Hara

Although the conventional acid-reductive leaching method effectively extracts copper (Cu) and cobalt (Co) from Cu–Co oxide ores, efforts to enhance hydrometallurgical performance are ongoing. This study evaluates the influence of sulphuric acid (H2SO4) and sodium metabisulphite (Na2S2O5) on metal extraction from Zebesha Cu–Co oxide ore using ferrous sulphate heptahydrate (FeSO4·7H2O) and ferric sulphate (Fe2(SO4)3) as lixiviants. Ore samples (<150 μm) were leached at ambient temperature for two hours, and metal concentrations were determined via X-ray fluorescence analysis. In the FeSO4·7H2O system, Co, Mn, and Ni recoveries increased w=ith Na2S2O5 concentration, reaching a maximum of approximately 80% Co at 150 kg/t, while Cu recovery remained below 5%. Conversely, with Fe2(SO4)3, Cu recovery peaked at 88% at 50 kg/t Na2S2O5, then declined to 79% at 150 kg/t. The addition of H2SO4 improved metal recoveries in both systems. Notably, 60 kg/t H2SO4 yielded 92% Cu extraction in Fe2(SO4)3, while Co, Ni, and Mn remained below 40%. However, in FeSO4·7H2O, Co recovery improved from 40% to 84%. These findings suggest Na2S2O5 is more effective for cobalt extraction with FeSO4·7H2O, whereas H2SO4 enhances copper extraction in Fe2(SO4)3.

Oct 24, 2025

Due to deposit shape and dimension, narrow vein makes reserve modeling, geological control, stope design, drill and blasting more challenging. It needs high standard quality control as errors can be created easily, which could cause significant amount of ore loss or dilution. From channel sampling, survey control, reserve modeling, drill hole design, blasting, communication with underground drillers to backfill, this paper illustrated every step and its quality control of a long hole stope mining. Compared to other narrow vein mining methods (cut and fill and shrinkage), long hole stoping means higher production, less labor, and significantly lower cost when deposit characteristics allowed.

Jan 1, 2012

By R. W. Lawrence, O. Lopez

Many gold deposits in the world have not been developed clue to the presence of copper and other base metals which can cause metallurgical and environmental challenges clue to the formation of base metal cyanide complexes. SART technology (sulphidization-acidification-recycle-thickening) can resolve these issues by recovering copper as a high grade sulphide concentrate, recycling the associated cyanide back to the gold leach, and eliminating the downstream environmental liabilities. Project economics can be improved substantially, leading to a positive re-evaluation of new and existing gold-copper projects. Some aspects of the design and operation of two recently commissioned SART plants will be discussed.

Jan 1, 2011

By J E. Everett

An essential requirement of product quality control in the mining industry is to be able to reliably predict key quality properties of finished product from the data available before the extraction of the ore. From a production viewpoint, the unit of data collection is generally the input and output data set for each shift of crusher production, but could be any period where mine precrusher data can be reliably matched with product data.This paper demonstrates that linear regression models can be used to predict crush grades from blast grades, even where the crush material is blended from multiple sources or pits for each of which differing regression models might apply. The advantage of using increasingly complex regressions models to match the available data to give increasingly more powerful models is examined. The best model for any application will be a balance between required predictability, available data and the business’ tolerance for complex models.The regression modelling approach has several advantages over the more classic method of run-of-mine (ROM) crusher trials, which will be discussed.The models can use any predictor variable such as grade, geotype and in situ density provided the preextraction data set can be reliably matched with post-crusher data and is significant as a predictor. The models have been used extensively in the generation of the daily crusher plan with the aim of maintaining finished product grade. This approach has also been used associated with exploration drilling and long-term planning.It is acknowledged that there are inherent problems in fitting lump and fines grade to a linear model. However, these problems are minor when they are used for interpolation within the window spanned by the shift blend records used to produce the model. This paper discusses some of the issues limiting linear regression models in this application, and suggests methods enabling consistent models to be formulated

Sep 5, 2011

By G De Tomi, R Sousa, A Lapworth

One of the current challenges for iron ore producers is the ability to respond to changes in ROM stockpile specifications in a quick and cost-efficient manner. The decision-making process to respond to such changes is normally associated with grade-control and short-term mine planning activities, from where new operating instructions to the mine are provided. Mines are under increasing pressure from changes in the industry, such as a scarcity of skilled staff; a higher turnover of skilled employees and tighter product specifications. The quality of operational activities easily suffers as a result of these pressures. The technology that supports operational activities is often poorly implemented, which results in systems being unsustainable and poorly understood by the organisation. All successful technology implementations rely on the people, processes and technologies involved being well understood. Because of the complex nature of mining, the processes that underpin mine planning, scheduling and operational control are often not well defined. This results in activities undertaken by individual departments being poorly integrated. Datamine has developed a set of tools and methods for decomposing; capturing and documenting processes and ensuring those are embodied in implemented solutions. A case study of such a solution is the GEROS planning system, which has been successfully implemented at CVRDÆs Southern Iron Ore System, in Minas Gerais, Brazil.

Jan 1, 2005

By M Brockman, M Cowan, A Robeson

"Sunrise Dam Gold Mine (SDGM) is located 820 km from Perth, 220 km from Kalgoorlie—Boulder and 55 km south of Laverton in Western Australia. The SDGM main pit had successfully operated since 1997 and was due to be completed during 2012. An opportunity existed to extract the high-grade crown pillar – 600 kt @ 7 g/t for 135 koz by either open pit or underground methods.The crown pillar was the 60 m (vertically) thick remaining part of the high-grade Cosmo orebody between the top of the paste filled underground mine stopes and the planned base of the final open pit shell.There were two major difficulties being considered when choosing the underground or open pit options:a major wall failure in the upper section of the main pit wall directly above the crown pillar restricting access from the base of the open pit to the top of the crown pillarimpact of a high rainfall event while the crown pillar was being mined from either surface or underground resulting in flooding of the underground mine workings.This paper will discuss the following issues:the process to identify and evaluate the risks in both options using knowledge based modelling software; this technique allowed the evaluation of a complex set of assumptions to arrive at the preferred optionremediation of the Watu failurethe selection of the preferred option and the challenges encountered before, during and after the extraction of the crown pillarthe planning and geotechnical work to ensure the safe extraction of the crown pillarsuccessful outcomes transitioning from open pit operation to a solely underground operation.Citation:Robeson, A, Cowan, M and Brockman, M, 2016. A Case Study on the Assessment, Planning and Extraction of the Crown Pillar at Sunrise Dam Gold Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 115–136 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By C. M. Anson

This paper describes the progresses used in the manufacture of steel wheel-centres, tyres and axles at the works of the Commonwealth Steel Products Co., Newcastle, N.S.W., Australia. The plant is adjacent to the Northern railway and consists of three main buildings, namely: the foundry, the forging and rolling shop, and the machine shop. The foundry contains a 6-ton Heroult electric furnace, together with all necessary mechanical appliances for moulding. Reheating furnaces, steam hammers and tyre rolling mill are installed in the forging shop. The machine shop contains lathes, boring machines, and hydraulic presses. Until this plant commenced operations all wheels used in Australia were imported, previ.ous to the war, from England and Germany, and latterly from England only. Besides being of great benefit to the country in that there is now a domestic source of supply of these articles, there is also the advantage of retaining the home market; and in addition, a small portion of the population are now engaged in highly technical occupations requiring a great degree of skill. The plant began to operate in October 1919, and by 1921 was in a fair way to meet the domestic demand for those articles of railroad equipment which it manufactures.

Jan 1, 1925

By M. Goto, F. Kubota

"In this study, we show the successful separation of rare earth metals, which are indispensable elements for the high-tech industry, from a solution containing a metal mixture by using a liquid-liquid extraction and liquid membrane based on ionic liquids. We employed newly synthesized N, Ndioctyldiglycol amic acid (DODGAA) as an extractant for rare earth metals. The DODGAA exhibited a high affinity for rare earth metals such as Y, Nd, Eu and Dy and the extraction efficiency was greatly enhanced in ionic liquids (ILs). Furthermore, stripping of the metals was readily achieved by using an acid solution. INTRODUCTIONRare-earth metals have important applications in cutting-edge technologies employed in the electronics, information technology, and automobile industries. As Japan does not have many natural metal resources, maintaining a steady supply of imported rare-earth metals is important. The total amount of rareearth metals imported into Japan was 19,000 tons/year in 1996, and this amount increased to 40,000 tons/year over the following decade (Kramer 2010). Japan is now one of the world’s major importers of rare-earth metals (Kramer 2010). However, more than 90% of the rare-earth metals imported into Japan come from China, the world’s leading supplier of rare-earth metal resources, due to their low costs. This situation made us realize the importance of a second resource of rare-earth metals: “urban mines” or discarded electronic waste. Rare-earth metals are generally separated from their natural ores by solvent extraction. However, since urban mines have different metals and the concentrations of rare-earth metals are usually low, highly efficient separation and recovery methods are required for rare-earth metals.Recently, ionic liquids (ILs), which are molten salts at room temperature, have attracted considerable attention since they are novel, environmentally friendly solvents (Kubota & Goto, 2006; Han & Armstrong, 2007). The use of ILs in liquid-liquid extraction of rare-earth metals has been reported (Kubota et al., 2012). In some cases, the IL-based systems showed better extraction ability and selectivity than those showed by the conventional organic solvent extraction systems(Nakashima et al., 2003, 2005; Hirayama et al., 2008; Fang et al., 2012). Therefore, more efficient solvent extraction processes by using ILs can be developed. In this study, we investigated solvent extraction processes in which ILs are employed and discuss the possibility of using ILs in the separation and recovery of rare-earth metals from electronic waste."

Jan 1, 2012

By Phillip N. Yasnowsky

"In this Bureau of Mines report, the Federal income tax treatment of mineral exploration and development expenditures is summarized, and changes in the tax treatment of these expenditures since 1951 are detailed and analyzed. Although no attempt is made to establish causal relationships, major tax changes favorable to exploration and development activities did occur in 1951 and 1966 when the Nation was engaged in military actions and the economy was expanding. More recent changes have been unfavorable to exploration and development and were parts of major tax reform efforts. INTRODUCTIONThis Bureau of Mines report discusses the Federal tax law provisions relating to mineral exploration and development expenditures. These provisions, contained mainly in sections 616 and 617 of the Internal Revenue Code of 1954 (Title 26 of the U.S. Code), apply specifically to minerals (other than oil and gas), and thus are of interest to the Bureau of Mines.Bureau of Mines involvement in this subject stems from the legislative mandate in the 1913 amendments to the Organic Act of 1910 (the Act creating the Bureau) to conduct economic investigations of the mineral industries. Congressional concern with the financial conditions in the economic and mineral industries was expressed more recently in the Mining and Minerals Policy Act of 1970 and in the National Materials and Minerals Policy, Research, and Development Act of 1980. The General Accounting Office recommended in 1976 that the Department of the Interior ""identify and evaluate laws and agency programs that affect maintaining and developing a sound and stable domestic mining and minerals industry"" (17, p. iii). 2Taxes, a source of revenue to governments, are a cost to private firms. Thus, taxes directly affect private sector profits, and unique tax provisions are designed to encourage (or discourage) activities such as agriculture, construction, or mining. Even the international competitiveness of the domestic mineral industries may be affected by taxes because many minerals are traded in world markets."

Jan 1, 1985

By O. C. Blade

This report on the properties of burner-fuel oils produced during 1956 was issued under a cooperative agreement between the American Petroleum Institute and the Bureau of Mines, United States Department of the Interior, at the request of the Oil-Heat Institute of America and the petroleum industry. This survey is the second for this type of fuel, the first being made in 1955. 2/ The surveys are conducted to provide information on the characteristics of burner-fuel oils now manufactured for sale. They are similar in pattern to the diesel-fuel surveys, conducted since 1950, 3/ and are not intended to conflict with but rather to supplement them. The importance of fuel oil has resulted in the need for more information by the petroleum industry, manufacturers of heating appliances, and consumers regarding the types and qualities of the fuels currently being marketed. Samples of burner-fuel oil typical of their manufacture during the early part of 1956 were analyzed by the refiners in accordance with instructions from the subcommittee on fuel surveys of the Automotive Research Committee of the American Petroleum Institute, Results of the analyses were transmitted to the Bureau of Mines where the data were studied and compiled as shown in the tables of this report.

Jan 1, 1956