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By Kefton H. Teague

Olivine is a mineral containing a mixture of forsterite (Mg,SiO,) and fayalite (Fe,SiO,) in solid solution. The name "olivine" was first applied by Werner in 1790 (Hunter, 1941) because of the olive-green color of the mineral. Uses The principal use of olivine is in various foundry applications. Perhaps the largest tonnage is utilized as a special foundry sand for mold-making in brass, aluminum, and magnesium foundries (Schaller, 1957, 1958; Snyder, 1957). Olivine was first used as an industrial mineral in the early 1930s for a refractory material (Anon., 1970; Hunter, 1941). As a refractory raw material, olivine was first introduced in the United States as handcobbed, selected, shaped blocks of crude olivine. This use met with limited success. More recently, finely ground olivine blended with MgO and pressed into bricks, which are then fired, have found use in glass tank furnaces and open-hearth furnaces. Ramming or gunning mixes for basic furnace linings also utilize olivine. Olivine has been used in ladle linings with varied success. In Europe, substantial tonnages of olivine are utilized in refractory brick for night storage heaters (Anon., 1970). A limited amount of olivine has been used in the past as a fertilizer (magnesium source) and has been fused with rock phosphate to produce a magnesium phosphate as a plant food. The relatively high magnesia (MgO) content of olivine also attracted attention to it as a potential source of both magnesium compounds and as a source of metallic magnesium (Bengston, 1956; Hunter, 1941). Industries using olivine have not standardized specifications. Normally, producers supply a product which meets individual customer requirements. Such requirements involve type and amount of impurities, grain size of product, refractory characteristics, etc. Geology Olivine occurs commonly as accessories in basic igneous and basic metamorphic rocks. Economic deposits are of magmatic origin and are restricted to essentially the dunite variety of periodotite. Dunites are medium to coarse- grained crystalline rocks, generally reddish brown on weathered outcrop, and are composed primarily of olivine.

Jan 1, 1975

By Coppock BW, Scott TC, Firkin GR

The pollution control measures taken on the Imperial Smelting Process (ISP) operated at Cockle Creek are described together with environmental monitoring strategy and the statutory restraints applied in New South Wales. An outline of developments in the gaseous, liquid and noise control areas is given.

Jan 1, 1975

By Sidney Katell

This Bureau of Mines study estimates capital investment, operating costs, and selling prices for three underground bituminous mines producing coal with annual production ranging from 1.03 to 3.09 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of December 6, 1974, under the Bituminous Wage Agreement of 1974, and costs for material and equipment are based on 1975 indexes Initial capital investment ranges from $26,498,500 for the 1.03- million-ton-per-year (MM tpy) mine to $67,173,300 for the 3.09-MM-tpy mine. Total capital investment ranges from $37,437,500 to $92,984,300 for the same mines. Corresponding selling prices for the coal range from $14.83 to $13.26 per ton, assuming a 15-percent discounted cash flow rate of return after Federal income taxes.

Jan 1, 1975

By Blair R. Benner, Ronald J. Roman

The rate of acid leaching of malachite from a sandstone ore was shown to be controlled by the diffusion of H+ ions through the host rock. The kinetics of the reaction can be expressed by a shrinking core model. Equations for calculating effective diffusivities from an "infinite" slab and a cylindrical core were derived. The effective diffusivity, of H+ ions in a sandstone ore was measured.

Jan 1, 1975

By Fred N. Kissell

Air recirculation caused by dust scrubbers at coal mine working faces was examined by the Federal Bureau of Mines with regard to the potential hazards caused by a possible buildup of methane gas. A theoretical analysis indicated that there was no apriori way to predict the effect of scrubber recirculation on methane concentration levels. Experiments conducted in a full-scale model of a working face area indicated that methane levels were dependent to a great extent on the location of the scrubber exhaust, but that the scrubber recirculation did not substantially increase the methane concentration above those levels that would have prevailed were the scrubber not in operation. An analysis of two underground scrubber trials showed that the scrubbers had no significant effect on methane levels, and a review of explosions attributed to recirculation showed that these were characterized by a lack of fresh air as well as recirculation. It was concluded that high methane levels are due more to a lack of fresh air than to recirculation.

Jan 1, 1975

Willemite mineralization was discovered in 1966 in the North Flinders Ranges of South Australia, in the course of a stream sediment sampling programme. Further work outlined a total of nine separate willemite occurrences in the Copley/Beltana area, and ten small deposits in the Toondana area south of Parachilna. Mineable reserves of 1 000 000 tonnes grading 36.8% zinc were outlined in three deposits in the Copley/Beltana area and campaign mining of the Main Orebody commenced early in 1974. The main group of deposits all occurred within red, dolomitized Cambrian Ajax Limestone, and most are associated with significant thrust faulting. The area of the Main Orebody group of deposits has been intensely fractured, and the surrounding dolomites are often brecciated and contain up to 5% zinc. Lead and arsenic mineralization are minor components of the main group of deposits. Masses of Middle Proterozoic Willouran Formation crop out adjacent to or close to most of the deposits in the Copley/Beltana area. The Willouran is frequently highly sheared, brecciated, and often contains large inclusions of younger formations. It is believed that most of the Willouran outcrops represent piercement structures.

Jan 1, 1975

Of the energy resources present in Australia, coal and uranium are by far the largest. These two resources ap- pear sufficient to satisfy Australia's energy needs beyond the immediately foreseeable future and long after the natural petroleum resources are exhausted or have ceased to play a significant role. By that time, coal could be converted in plants of very large size to synthetic liquid and gaseous fuels which will be used as substitutes for pet- roleum fuels, particularly for transport. The basic role of uranium will be to supply electricity from nuclear power stations for heat and power requirements, thereby freeing non-coking coal largely for conversion purposes. The establishment of these enterprises will require a massive national effort and a high degree of co-ordination at the planning stage.

Jan 1, 1975

By Belcher C. B

The Groote Eylandt manganese ore deposits contain mainly pyrolusite and cryptomelane with lesser amounts of the manganese minerals lithiophorite, todorokite, psilomelane, and nsutite. The major non-manganese minerals which occur are quartz, kaolinite, and goethite.Determination of the mineralogy relies mainly on x-ray diffraction analysis. Quantitative methods for the determination of pymlusite and cryptomelane in Groote Eylandt manganese ores have been developed, A large amount of isomorphous substitution may occur in the manganese minerals and a number of minor and trace element associations have been noted. A correlation has been established between the potassium and cryptomelane contents for a wide range of ore types. Anomalous calcium, magnesium, and sodium values occur in samples containing todorokite, and barium is associated with psilomelane. Groote Eylandt lithiophorite appears to contain negligible amounts of lithium (<O· 05 per cent).A relationship between the H20+ and the Al203, K20, and Fe203 contents has been estahlished indicating that much of the combined water content is due to the presence of kaolinite and goethite, and cap be removed by beneficiation of the ore.

Jan 1, 1975

By Robert Lee Stahl

Comprehensive field tests were made by the Federal Bureau of Hines at the Conda open pit mine near Soda Springs, Idaho, to determine whether surface geophysical techniques could be used to detect and delineate faults in phosphate deposits. The tests included seismic refraction, magnetometry, electrical resistivity, and airborne photography. Of the several geophysical techniques tested in the field, horizontal resistivity profiling was the most effective method for diagnosing faults. The method is quick, inexpensive, accurate, and can be easily used by mining company personnel to detect and delineate faults.

Jan 1, 1975

To allow routine measuring of the exposure of underground workers to N02 from diesel engines and residual gases from blasting. The Approach: A miniature sampler absorbs NO2 which can be measured using a simple method adaptable to both multiple automatic analyses or individual on-site analysis. How It Works: The NO2 sampler is encased in a plastic tube approximately half the length of an ordinary ball point pen and clipped to an underground worker's hard hat. Removal of the end cap activates the personal sampler. Air from the working place enters the open end and diffuses at a controlled rate down the tube interior. The diffusion rate is dependent on tube dimensions (ratio of cross-sectional area to length). The closed end of the tube contains stainless steel mesh which is coated with triethanolamine (TEA) for absorbtion of all NO2 reaching it. Other oxides of nitrogen are not absorbed. The amount

Jan 1, 1975

By F. P. Haver

A method to recover copper and elemental sulfur from chalcopyrite concen¬trate, using a ferric chloride leach, CuFeS2 + 3FeCl3 ? CuCl + 4FeCl2 + 2S, was reported by the Federal Bureau of Mines in 1971 (Report of Investigations 7474). Since that time, additional work has been done to improve certain steps in the procedure; that is, the recovery of sulfur from the leach residue, the recovery of copper and iron from the leach solution, and the regeneration of the leach solution. It was determined that over 99 pct of the elemental sulfur in the leach residue could be extracted at ambient temperature with an ammonium sulfide solution. Heating the pregnant solution precipitated crystals of rhombic sulfur (99.5 pct purity) and liberated ammonia and hydrogen sulfide for recycle. Copper with a purity in excess of 99 pct was obtained from the leach solution by electrolysis, using a diaphragm cell, with an energy requirement of less than 0.7 kW-hr/lb. Metal was deposited as a weakly adherent powder that could be easily dislodged from the cathode and withdrawn continuously from the cell in the form of a slurry. During electrolysis, part of the Fe(II) was oxidized to Fe (III) at the anode so there was no chlorine evolution. The leach solution was regenerated by direct oxidation of the spent electrolyte with air or oxygen in a turboaerator at 80° C. This precipitated the iron dissolved during leaching in an easily filterable form, Fe203.xH20, and converted the remaining Fe(II) to Fe(III).

Jan 1, 1975

Drilling, Blasting, and Ore winning A General Meeting and Colloquium on the above subject was held on November 13th, 1974, at Kelvin House, Johannesburg. Professor R. P. Plewman (President) was in the Chair. The Colloquium was attended by 235 delegates and was opened by the President at 09h30.

Jan 1, 1975

By G. L. Gates

The waters used to waterflood the Wilmington oilfield were studied by the Bureau of Mines, in cooperation with the city of Long Beach, Calif. Increases in the pressure of the injection wells indicated that they were being plugged by materials suspended in the waters. This study was made to identify the suspended materials, determine their origin, and find methods of preventing their formation. The suspended oil-coated materials were iron sulfide, barium sulfate, calcium carbonate, clay, and sand (or silica). Results indicated that the sulfide, which was as high as 90 milligrams per liter, was the product of sulfate-reducing bacteria. The injection of ocean water increased the sulfate content of the waters in the petroleum reservoirs from 3 to 250 milligrams per liter, thereby furnishing sulfate for growth of the bacteria. The waters were supersaturated with barium sulfate. Laboratory tests showed that sulfide could be removed from the waters by adding iron at a cost of 1 to 2 mills per barrel. The solubility of iron sulfide and calcium orthophosphate in the injection waters was also determined.

Jan 1, 1975

The objective of this condensed handbook is to provide the inspector with guidance for recognizing hazards from inhalation contaminants in above ground work areas of underground and surface coal mining and processing facilities and evaluating these hazards by collecting samples or making field determinations and interpreting the analytical results. It will be carried with the inspectors during their surveys. The complete handbook should be left in their offices except for Appendix II which lists the compositions of products found in previous surveys. There are several portions of the condensed handbook which should prove most useful to the inspectors. The names and locations of these portions are listed below: Procedure for an Industrial Hygiene Survey (Page 2-1) Survey Check List (Page 2-3) Rules for Determining if Sampling is Required (Page 2-2) List of Most Frequently Encountered Contaminants (Page 2-5) List of Candidate Contaminants and their Sampling Conditions (Page 2-A) Interpretation of Results (Page 3-8) For obtaining information not available from the above mentioned portions of the handbook, the inspector is directed to the Table of Contents, and the Glossary of Terms (Appendix I).

Jan 1, 1975

By Brian F. Osborne

A continuous on-line particle-size analysis system for solid/liquid suspensions is described. The basic sensor utilizes a centrifugal principle to separate particles according to size, the resultant separation being measured by means of beta-ray attenuation. Results obtained when analyzing a variety of materials at sizes from 65 mesh (210 µ) to 20 w are discussed in detail. Accuracies better than 2% are demonstrated. The effects of particle specific gravity, and mixtures of materials of diverse specific gravities, are discussed from both a practical and a theoretical viewpoint. It is demonstrated that particle specific gravity has a minimal effect on the size reading obtained. This renders the instrument suitable for handling materials where the ratio of light to heavy component may change. The design of the first commercial installation of this instrument is described in detail. This installation will be capable of analyzing three streams in sequence, measurement at three particle sizes being effected on each stream.

Jan 1, 1975

By Ann G. Kim

Methane in coal constitutes a serious hazard in coal mining. Draining the methane in advance of mining can mitigate this hazard, conserve energy, and offer economic benefits. This Bureau of Mines report evaluates the Pittsburgh coalbed in Greene County, Pa., to determine if advance drainage is feasible. The gas content of virgin reserves in Greene County is estimated at 100 to 200 ft3/ton, a total of over 370 billion ft3 of gas in an area approximately 310 mi2. Because of the similarity to natural gas, drained coalbed gas could be recovered and added to pipeline supplies of natural gas. The value of conserved gas would offset the cost of drainage and extend energy resources.

Jan 1, 1975

By J. R. Allsup

The Bureau of Mines studied the characteristics of simulated coal gas as an automotive fuel in two multicylinder vehicles in a standard and high-compression-ratio engine configuration. While using simulated coal gas fuel, increasing the engine compression ratio improved the fuel economy and vehicle performance but increased hydrocarbon emissions by 40 pct. photochemical reactivity of exhaust hydrocarbons was found to be extremely low using the coal gas fuel. An oxidizing catalyst used with the simulated coal gas fuel eliminated all but trace amounts of carbon monoxide and reactive hydrocarbons in the exhaust. Spark gap geometry and firing voltage were varied and, within the range tested, had little effect on vehicle performance and emissions using simulated coal gas fuel.

Jan 1, 1975

By Nils A. Eilertsen

This Bureau of Mines report describes the unit cost procedure for estimating direct development costs within a cave block in an undercut block caving mine. Costs of supervision, labor, equipment, and supplies are combined to build a unit cost for each type and size of mine development opening in the block. These costs are then combined to estimate the direct cost for developing a ton of ore. Operating data from several domestic metal mines are combined with a hypothetical mining system to illustrate the costing procedure.

Jan 1, 1975

By G. G. Huggins

A demonstration project has been completed to reduce the operator sound level of an underground service vehicle, a personnel dispatch wagon, to go dB(A) or less. The program objective was to implement quieting recommendations made on an earlier study for the USBM n diesel-powered mine equipment. The manufacturer and mine to which the vehicle was going actively participated in the program to ensure a product that was not only quiet, but useful. The key element of the quieting package is an engine part a1 enclosure, which, with several complementary noise control components, reduced the operator sound level 14 dB, from 101 dB(A) to 87 dB(A). The vehicle underwent a 4-month trial period, with no degradation in the quieting package. Mine personnel reported no maintenance difficulties, and were enthusiastic about the dispatch.

Jan 1, 1975

By D. G. Kuehn

Studies were conducted by the Bureau of Mines to determine the positive ions and neutral species produced in glow discharges of gas streams containing 1.0 percent NO in helium, 29 percent dry air in helium, and 1.06 percent NO in N2, Mass spectrographic measurements were conducted for gas pressures from 2.3 to 10.0 torr and dc currents from 10 to 20 mAo Ion species observed included NO+, N2 +, O2 +, N+, and 0+ with lesser amounts of He+, He2+, and N02+. Variations in various ionic and neutral species with discharge duration were interpreted to be consistent with an electrically induced dissociation of NO to produce N2 and O2. No nitrogen oxides were observed to form in glow discharges of the helium-air mixture.

Jan 1, 1975