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By L. Telfer

Summary During Palaeozoic time, there were deposited in the Canadian Rockies four beds of phosphate rock, ranging in age from Mississippian to Jurassic. Two of these beds are of probable economic importance if some means of separating the phosphate from the gangue can be devised. All the more important beds of phosphate rock so far discovered are just behind the front ranges of the Rocky mountains, within fifty miles of the prairie lands of Alberta. Mining conditions are favourable, with an abundance of timber and ample power available. The phosphate beds are all of the sedimentary type, and they all occur, apparently, at the same stratigraphic horizons over a wide area. The conditions necessary for deposition evidently occurred at several different periods in geological time, and were widespread. The most important factor appears to have been the condition of the land surface surrounding the basin of de-position. Both oolitic and nodular phosphate were laid down under nearly similar conditions. Introduction Following the discovery of phosphate rock in Idaho and Montana, search was commenced in Canada to determine whether formations of similar age in the Canadian Rockies carried similar beds of phosphate. The most widespread search has been that undertaken by the mines department of the Consolidated Mining and Smelting Company of Canada. The following paper will discuss some of the results of this exploration.

Jan 1, 1933

By Jamal Asfahani

Abstract - Natural gamma ray well logging, an effective tool in geophysical prospecting, is used to investigate the radioactive and phosphatic layers in the Khneifiss mine in Syria. The interpretation of the gamma ray measurements, using numerical methods of analysis developed previously and applied successfully in some phosphatic areas in Syria, make it possible to define precisely the phosphate thickness from place to place in the study area. This technique has been successfully applied while studying seven boreholes in the area. Sixty-three core samples from phosphatic layers in the boreholes have been analyzed, using gamma ray spectrometry for the determination of P2O5 , U, Th, and K. Good correlation between P2O5 content and U concentration has been found. The total count gamma logs correlate reasonably well with the U core analysis, suggesting that radioactive equilibrium exists in the U decay series. These gamma logs can be therefore used effectively to quantitatively map the distribution of P2O5 and U. The characteristics of both subsurface phosphatic sand and phosphatic rocks have been investigated and outlined using a statistical approach. The affinity of uranium to some trace elements such as V, Sr, Cu, and Ni has been verified using correlation matrices of these elements.

Jan 1, 2002

By A. E. Cameron

The theory of atomic distribution of the stranger atoms in the space lattice of the solvent metal has been well developed by Rosenhain. It has long been known that the addition of one metal to another to form a solid solution increases the strength and hardness of the solvent metal. This increase is practically proportional to the amount of added substance up to the limit of solid solubility. To account for this increase in hardness and strength, Rosenhain assumes that the stranger atoms occupy positions on the solvent metal space lattice. Atomic attractions about the stranger atoms will not be the same as in the case of the pure metal, and there will thus be a disturbance of the orderly arrangement of the atoms on the space lattice, or a distortion of the lattice. Such a disturbance would interfere with the ease of slip along the planes and would thus tend to promote strength and hardness. Rosenhain notes that not only may there be a local disturbance of the lattice about the stranger atom but there may well be also a measurable change in the dimensions of the lattice as a whole. The relative amounts of local and general distortion of the lattice will depend upon the nature of the lattice itself. As Rosenhain says, "If the lattice is comparatively soft and flexible the distortion is likely to be largely local. In a stiff lattice, however, local distortion will be resisted and there will be a correspondingly increased general distortion."

Jan 1, 1927

By L Tafaghodi Khajavi, M. Barati

The distribution of phosphorus between solid silicon and iron-silicon melt was determined to investigate the degree of phosphorus removal from silicon by solvent refining with iron-silicon alloys. The distribution coefficient which is the ratio of the mole fraction of phosphorus in solid to that of liquid is as follows: 0.22±0.02 (1310°C), 0.29±0.02 (1260°C) and 0.33±0.02 (1210°C). The removal percentage of phosphorus is: 84.2% (1310°C), 72.5% (1260°C), and 63.7% (1210°C). The average phosphorus content of produced silicon in the proposed solvent refining process would be over two times less than that of the conventional directional solidification. The values of interaction coefficient of phosphorus on iron at different temperatures were obtained as -3460±155 (1310°C), -3595±159 (1260°C) and -3694±119 (1210°C). Self interaction parameter of phosphorus at different temperatures are as follows: 68±4 (1310 ?C), 78±10 (1260 ?C) and 103±19 (1210 ?C). The calculated values for distribution coefficient of phosphorus at infinite dilution are: 0.22±0.00 (1310°C), 0.30±0.00 (1260°C) and 0.34±0.00 (1210 °C).

Jan 1, 2015

By Michael Bowker

Au/TiO2 catalysts were prepared by incipient wetness impregnation and tested for the room temperature photocatalytic reforming of methanol in aqueous solution. These catalysts proved to be more active, on a molar basis, than Pd/TiO2. The dependence on loading of gold was different from that of palladium, showing a double maximum in yield at 0.1 and 2 wt. % with low rate below 0.01% and above 10%. A model is proposed for the reaction involving band gap excitation of titania electrons which are used to oxidise the methanol via adsorbed CO. With palladium, photoreforming of CO and water can be achieved, but this is much less effective on gold, presumably due to the much weaker bonding of CO on Au.

Oct 1, 2003

By B. Van den Bogaert, K. Binnemans, T. Van Gerven

Europium is one of the most critical rare-earth elements due to the limited supply of this element combined with a high demand for red lamp phosphors. Therefore, the recycling of europium from end-oflife lamp phosphors has become increasingly important. Photochemical reduction of europium(III) to europium(II) and subsequent removal from rare-earth mixtures by precipitation as EuSO4 is a very selective and efficient method to recover europium from binary europium/yttrium solutions. It is shown that full separation of europium and yttrium is feasible from laboratory prepared non-equimolar Eu/Y mixtures up to a ratio of 1/20, which reflect the composition of red lamp phosphors. Optimal conditions were determined at pH 4 with isopropanol as a radical scavenger, which is a less harmful and toxic compound than the commonly used formic acid scavenger. Europium removal efficiencies of more than 95% were achieved, with a purity of 98.5% of the EuSO4 precipitate. The irradiance of the used light source, expressed in mW/cm2, has a large impact on the illumination time needed to remove europium from the solution. It is observed that higher irradiance results in a shorter induction time, i.e. a period during which virtually no europium is removed, and a faster removal rate once the induction time has passed. The photochemical separation technique was applied to recover europium from leached industrial red lamp phosphor (YOX) powder, with a Eu/Y ratio of 1/30. Europium recovery of 50% was reached with a purity of 96%, proving the feasibility of this method for the recycling of europium from end-of-life lamp phosphors.

Jan 1, 2016

By R. J. T. Charles

Introduction An apparatus that will measure the surface area of a few of the simple minerals with a high degree of accuracy has been described by J. W. Bell (1). His apparatus consisted essentially of a photometric device that would measure the turbidity of fine particle suspensions. Turbidity, in this case, was considered as a function of surface area. Bell's method of surface area determination seemed to offer possibilities of extension and improvement to the point where it might approach a general method of particle size measurement. Theoretical and Practical Considerations of the Photometric Method In order to illustrate how turbidity may be considered as a function of average particle size, and to indicate the type of results expected from a photometric method of particle size measurement involving turbidity, the following theory may be hypothecated. If a number of particles, considered as spheres of uniform diameter, are placed at random in the path of a beam of light, the following expression, which will give the change in light intensity as a function of the diameter of the particles, the specific gravity of the material, and the weight involved, can be formulated from the Beer-Lambert Law:

Jan 1, 1951

By D. R. Spink, G. L. Rempel, C. O. Gomez Bueno

"A morphological and chemical study of the Great Canadian Oil Sands Ltd. (GCOS) fly ash has been carried out. Extensive scanning electron microscopy, as well as light microscopy, showed that the GCOS fly ash consists of two fractions, one composed of unburnt or partially burnt irregular-shaped carbon particles and an ash fraction composed of transparent and opaque, often coloured, glassy spherical particles-some of them cenospheres (hollow spheres) and the others plerospheres (hollow spheres packed with smaller spheres). Microcrystals (0.1 to 0.3 um long) growing on the inner and outer surfaces of some of the spheres were also noted and found to contain more Fe, Ti, Ni and V than the spheres.The carbon-free GCOS fly ash particle size follows a lognormal distribution, with a geometric median particle size (by count) of3.8um and a geometric standard deviation of 1.84. IntroductionCanada's current energy situation strongly suggests that oil from the Alberta tar sands deposits will probably be recovered more extensively in the future. Today's commercially proven technology to recover oil from the Athabasca tar sands, as practised by Great Canadian Oil Sands Ltd. (GCOS), involves two major operations, namely: separation of the bitumen from the sand and upgrading of the bitumen to refinery oil; the production of significant amounts of petroleum coke and sulphur during the bitumen upgrading process. The bulk of the petroleum coke is burnt in boilers to fulfill the energy requirements of the entire operation. The boiler ash, which contains appreciable amounts of metals, such as vanadium, nickel, titanium, iron, aluminum and other elements, is collected in the boiler hoppers and cyclones of the petroleum coke-fired steam generation plants. Thus, as well as representing a petroleum resource, the tar sands represent a resource for vanadium and possibly other metals providing that metal recovery processes can be developed."

Jan 1, 1980

By M. Härting, D. T. Britton, M. Nzikou Mamboukou

"Copper containing different types of nanocomposites have been characterized for nanolabelling and ID. Three types of the rare earth nanoparticles were used for this study, the oxide and the sulphur compound of the Eu and Tb. Characterization techniques uses SEM, and Raman for morphology, chemical composition, and optical characterization respectively. It has been shown that it is possible to include the rare earth particle in a copper matrix without damaging its physical properties. INTRODUCTIONThe development of new materials, often involves the addition of new properties without changing the beneficial properties of the original material (Chen et al., 2009; Khana et al., 2007; Patil et al., 2008). Nanocomposites are nanostructured materials, whose structural elements including clusters, crystallites or molecules, of dimensions ranging between 1 to 100 nm (Moriarty, 2001), or a composite material where one of the phases is a one, two or three dimensionally nanostructured material (Nanotechnology, 2006; Wang, 2001). Nanocomposite materials research is a fast growing area due to the high demand for materials for specialized applications (Edelstein & Cammarata, 1998), such as biolabelling, magnetic storage media, solar energy transformation (Jisen et al., 2004), and resistance welding applications (Bessergenev et al., 1997; Kwon et al.,2006).The properties of the nanocomposite materials depend not only on the properties of their individual parent materials, but also on their morphology and the interfacial characteristics. Thus, significant efforts have been focused on the control of the nanoscale structures via innovative synthesis approaches. Therefore, novel materials of unique properties may be obtained by combining properties from the parent constituents into a single material (Balan, 2006; Garcia et al., 2009). Possible effects of nanocomposites in the original material may include changes in the mechanical properties such as hardness , wear resistance (Rafaja et al., 1987), and electrical properties (Britton et al., 2003). The inclusion process may therefore be used to tailor materials to have particular mechanical, electrical and optical properties (Das et al., 2009). However, to fully understand the nanocomposite, it is necessary to study the fundamental properties of both the host matrix and the inclusions (Li, 2008)."

Jan 1, 2012

By R. Saulters, M. Garshasb

The Transportable Moisture Limit (TML) is the copper concentrate moisture content beyond which liquefaction may occur during shipping. This study indicates that TML is a function of mineralogical characteristics of concentrate, which in turn may directly affect moisture retention properties. A comprehensive mineralogical and chemical analysis was conducted to determine the impact of composition and mineral content on concentrate’s TML. The analysis indicates that the high TML value is associated with particular minerals such as gypsum, swelling clay, muscovite and pyrite. Since higher TML values allow higher moisture contents for shipping, this property is desirable for concentrate inventory management and shipping flexibility. Scarcity of minerals that may increase TML contributes to limitations of shippable inventory. INTRODUCTION TML is the maximum moisture content of copper concentrate beyond which liquefaction may occur. Moisture content above the TML is considered a shipping hazard as it may result in loss of lives and cargo. The details of TML testing are given in ISO 12742:2007 (ISO 12742). In principle, TML is 90% of the Flow Moisture Point. The method of testing for Flow Moisture Point and TML is based on procedures that provide pulsations that simulate the cyclic force of ocean waves to determine moisture levels at which the onset of concentrate flow may occur. International Maritime Organization (IMO) provides guidelines for developing and approving TML testing and moisture determination in the context of its Moisture Management Plan (MMP) for shipment of copper concentrate cargoes (IMO 2013). The IMO regulations are specifically provided in MSC.1/Circ. 1454 “Guidelines for developing and approving procedures for sampling, testing and controlling the moisture content for solid bulk cargoes which may liquefy”. Since each port has its own operational characteristics, resource availability, peculiarities of governmental structure, and desired methods of interaction with the authorities, it is necessary to adopt the IMO guidelines to the local requirements. In order to establish a TML and MMP measurement system, it is required to implement and follow proper guidelines for the relevant procedures. For example, sampling procedures are developed in accordance of ISO 12743, “Copper, lead, zinc, and nickel concentrates – Sampling procedures for determination of metal and moisture content”. Moisture content of copper concentrate samples are determined in accordance with ISO 10251, “Copper, lead, zinc, and nickel concentrates – Determination of mass loss of bulk material on drying”. To assure strict adherence to the MMP procedures, the overall system needs to be integrated into the site QA/QC system, which would make them auditable and certified in accordance with standards such as ISO 9001, ISO 17025, and ISO 17020.

Jan 1, 2019

By S. Hosseinpour

Chromate conversion coatings (CCCs) are usually applied to these alloys to enhance their resistance to localized corrosion and to improve paint adhesion. The special properties of these coatings such as their low electrical contact resistance (ECR) make them suitable for satellites. This study is aimed to develop advanced CCCs with the proper appearance, morphologies and surface roughness and to evaluate their role on the ECR and thermo physical properties on hardened aluminium alloy of Alclad-7075-T6. Coating characterization was performed by means of scanning electron microscope (SEM) and atomic force microscope (AFM). ECR of coatings were measured by special laboratory designed instrument and a and c were measured by Emissometer and Reflectometer respectively. In addition, corrosion performance of the CCC-coated alloys was determined by 168 hr exposing to salt-spray testing in accordance with ASTM-B117. The results of accomplished experiments on the developed CCCs in this study have been agreeable concerning available acceptability criteria for satellite surfaces.

Jan 1, 2007

By Abdelhak Bentriou

The choice of tool for the first well of an oilfield or gasfield is an important factor, given that we will be drilling with the same type of tool for the entire phase and explains why we need to have another type for comparison based on the efficiency of the tool and its ability to crush the rock, and the wear of different types of tools. Development of theoretical and practical tests to determine the optimal regime for drilling is required to take into account the characteristics of rock layers crossed. Classification of boring tools is based on the geometry of the teeth and depends on the hardness, the abrasiveness of rocks as well as their hydraulic system, but it is better to classify them according to the working conditions with a coefficient designating a discriminant. This is called physical characteristic of the drilling tool. The goal is to designate each element of the tool by a coefficient. Results were obtained from laboratory tests. Modeling the initial rate of progress by different types of tools allowed us to determine an adequate mathematical model of the speed initial progress in clean conditions. Using experimental data and statistics we have established the mathematical model of the average speed of progress as a function of time. With these equations we can determine the wear evaluation and analysis of these factors as an approach to classification according to their characteristics. The main equations for the selection of drilling tools will be based on the optimization of drilling parameters for each type of tool. After analysis, we choose the tool that gives a better forward speed with an optimal load and axial rotation.

Aug 1, 2013

By Gordon Sproule

THE papers presented to the Institute, and published in the BULLETIN, in the past three years, may be classified as follows: Geology, Mining, and Milling 89 or 58.5 per cent Smelting, Refining, and Refractories 17 " 11.2 " Mechanical and Physical Metallurgy 7 " 4.6 " General (Economics, Welfare, etc.) 39 " 25.7 " Total 152 100 These figure~ should be excuse enou.gh for. the present paper. As indicated by the title it is proposed: I.-To review briefly some of the more recent developments of Physical Metallurgy; and 11.-To show how Physical Metallurgy functions as the link between mining and production metallurgy on the one hand, and consumption engineering on the other hand. Io these days of specialization, papers of the kind being considered mostly gravitate to the American Society for Metals, the American Society for Testing Materials, the Institute of Metals, and the Iron and Steel Institute. In proof that there is a place for the newest and most specialized of these societies, the American Society for Metals, it may be said that in the Montreal Chapter there are 200 active members, and in the Ontario Chapter more than 200. Yet the overshadowing glamour of the mining industry proper, and the publicity it receives, result in an almost continuous dearth of students in metallurgical engineering at our universities. There are more jobs than graduates.

Jan 1, 1936

By M. S. Badollet

"The study of the physical properties of asbestos minerals requires a careful isolation of the fiber from the wall rock and, at a later stage, a comparison of these physical properties with those of fibers that have passed through the milling and beneficiation processes.The effects of mineral impurities, loss of fiber length and the formation of extreme fines (asbestic and/or associated minerals) often show up in the formation of special asbestos products as well as in the commercial production of asbestos papers, mill-boards, asbestos cement products, plastics and insulation materials, and in the filtration of blood plasma and wines.Numerous test methods have been developed in Canada and in England for use in the asbestos industry. Special treatments of asbestos fibers have been used to improve their physical and chemical properties and to eliminate impurities.Numerous problems connected with the use of asbestos fibers are discussed, such as the effects of asbestos on filtration, surface area, surface treatments using organic or inorganic materials, the surface charge on the fiber, the presence of magnetite and air pollution elimination. Biological studies on finely ground asbestos, when dispersed in 0.9 per cent sodium chloride solution and then sterilized and injected into hamsters, show that by reducing the dose, the tissue damage can be largely avoided. In these experiments, Arizona asbestos fibers were carefully extracted from the wall rock, finely ground, and examined chemically and micros-copically for any mineral impurities that might be present so that any effect on the hamsters would be directly due to the presence of the asbestos. The harsh Arizona fiber induced more extensive tissue response than the soft fiber when tested in hamsters."

Jan 1, 1969

By Tatsuya Oki

Tantalum capacitors can be found mounted on printed circuit boards of domestic appliances such as personal computers. These capacitors contain a considerable quantity of expensive metal tantalum and can be detached and liberated from printed circuit boards by impact breakers. In this study, the size and density distribution of the liberated electronic devices were investigated. Then, tantalum capacitors were recovered from other electronic devices using size separation and pneumatic gravity concentration methods. More than 70% of Newton's separation efficiency was obtained for tantalum capacitors. High Newton's separation efficiency could be also obtained for other types of electronic devices such as chip resistors.

Jan 1, 2011

By O. Laitinen, M. Rudolph, J. A. Sirviö, H. Liimatainen, R. Hartmann, University of Oulu

The increasing complexity of the ores composition worldwide calls for suitable collectors with specific properties, such as selectivity, wettability, and in regard to current regulations, environmental sustainability. Therefore, collectors have to satisfy many features to improve the efficiency of flotation processes. Cellulose nanocrystals gain more and more interest due to the versatile synthesis routes which enable the integration of specific functional groups and components with different degrees of hydrophobicity within the molecular structure. Consequently, cellulose nanocrystals can be employed in flotation processes as depressant or collector molecules, respectively. Nonetheless, the usage of cellulose nanocrystals is still limited due to a lack of the characterization of nanocrystal-mineral interactions and the change of the surface wetting properties of minerals after adsorption phenomena between nanocrystals and minerals. In these studies, butyl-amine cellulose nanocrystal (BAC) and quartz are used as model system to investigate physicochemical properties of both, BAC and quartz, and examine the applicability of BAC in flotation processes. Therefore, the surface charge distribution and electrophoretic mobility of BAC and quartz are investigated and compared to understand the effect of electrostatic interactions between BACs, and BAC and quartz. Based on this, the adsorption of BAC on quartz is examined. Finally, microflotation experiments test the efficiency of BAC to be used in flotation processes. The flotation response is correlated to the specific surface charge of BAC revealing the dominant effect of surface charges on effective particle-bubble adhesions.

Jan 1, 2016

By Eugene Barsky

"At present, theoretical concepts of gravitational separation processes are mainly limited by the study of the interaction between a flow and a solitary particle. Then the main conclusions of this analysis are applied to a mass process. However, this analysis is absolutely insufficient, because some elementary phenomena such as the ingress of coarse particles into the fine product output and vice versa cannot be interpreted from its standpoint. It is also impossible to predict the results of the classification of a material with a specific granulometric composition on a specific apparatus on its basis.In the present paper, an extended model of the process is suggested. The model is based on the behavior of all the particles of a specific narrow size class, and not on that of an individual particle. Similarity criteria of the process, which were empirically derived previously, are obtained from the analysis of this model.INTRODUCTIONIn case of gravitational separation, a part of solid phase moves, as a rule, vertically upwards with the flow, while another part settles against the flow. This flow is extremely complicated and chaotic due to various random factors. Among these factors are mass interactions of particles with each other and with the apparatus walls, non-uniform character of concentration and velocity fields, turbulent vortices and local fluctuations, real particles shape difference from spherical one, etc.Particles rotation results in a transverse force (Magnus' effect). At the motion of a non-rotating particle in a non-uniform velocity field, a transverse force also arises (Saffman's effect).A great number of publications have been devoted to the account for all these factors in two-phase flows in recent decades. Very complicated models have been developed, but the problem has not been completely solved as yet [1, 3].At the same time, simplified models of the behavior of a solitary particle in a flow are being developed. Despite their schematic nature, such models often prove to be useful for establishing general laws of the process and its similarity criteria [1]."

Jan 1, 2016

By S Sokhanvaran

Electrodeposition of silicon from a cryolite based electrolyte at a relatively low temperature (1000°C) is a promising approach to generate high purity silicon. In order to obtain fundamental data pertaining to electrowinning of silicon from Cryolite?SiO2 melts, density and electrical conductivity measurements were made. A range of temperatures and SiO2 contents was studied for each property. It was found that while density has an inverse relationship with temperature, the dependence for electrical conductivity is direct. Increasing silica content up to the saturation limit (~ 5 wt%) increases the density whereas further increase in SiO2, lowers the melt density. On the other hand, the conductivity is lower for the melts with greater SiO2 content, at any temperature.

Jan 1, 2011

By Rufus L. Chaney

A new technology is available to the Ni mining and remediation community to “phytomine” Ni from mineralized or contaminated soils using rare plants which hyperaccumulate Ni to over 1% of shoot dry matter. Research has identified useful plant species, and even bred improved cultivars of Alyssum murale and Alyssum corsicum for commercial phytomining in temperate regions. All agronomic practices (fertilization, soil amendments, planting and harvest methods) needed for economic phytomining were identified to attain high yields and high Ni concentration in the biomass. In tropical regions, other species are available such as Phyllanthus which accumulate over 1% Ni in dry shoots. These species are perennial so they regrow after annual cutting to harvest biomass. Expiration of our patents on the technology opens the opportunity for other organizations which control Ni rich natural soils or contaminated soils requiring remediation to commercialize the technologies. Inexpensive methods to remediate/revitalize Ni contaminated phytotoxic soils using agronomic approaches have also been developed and demonstrated at Port Colborne, Ontario, but adoption is delayed until formal agreements with government are completed. These new simple remediation and profitable phytomining technologies can obtain Ni from soils which contain Ni well below levels considered economic for current mining technologies, and the plants biopurify the Ni so it is easy to recover Ni metal from plant ash by pyrometallurgical or hydrometallurgical technologies. Although increasing pH decreases the solubility of Ni in all soils, raising pH increases Ni accumulation by Alyssum species. Hence usual chemical extraction methods for phytoavailable soil metals such as the DTPA- or NH4-OAc-extraction cannot predict Ni accumulation by Alyssum species.

Jan 1, 2016

By W. P. Corking

"The purpose of this paper is to describe the relationship of the goldbearing ore to structure at the Pickle Crow mfoe. Information beyond this scope may be found in the reports and papers of Hurst( l), Bothwell(2), Thomson(3) , and Monette( 4).The property lies on Crow river, in Patricia district, 80 miles northeast of Allanwater, and about 125 miles northeast of Sioux Lookout on the Canadian National railway. From April of 1935, when the mill began operation, to the end of 1944, a total of 564,890 oz. gold and 49,275 oz. silver were recovered from 958,416 tons of ore.Mining on the property is at present carried on in two separate orebodies, the Howell and the No. 2 vein. Stoping has been carried on from every level on the Howell vein to a depth ot 2,450 feet below the surface and from several levels on the No. 2 vein through a mile long cross-cut on the 750-foot level to the Howell vein workings. A steadily increasing volume of ore is being obtained from the No. 2 vein.Each of the two orebodies consists of vein quartz with small amounts of other gangue minerals either in a single vein or a stockwork of veins. Both lie within sheared walls and carry gold in the free state. Fig. 1 shows the position of the veins with respect to the surrounding rocks. It will be noted that the delineation of the beds of iron formation shows that the lava flows and minor, interbedded sediments that make up most of the country rocks are areally folded and contorted.STRUCTURENearly all gold found to date in sufficient quantity and concentration to make ore in the Pickle Crow area is confined to these major quartz veins . Both strike a little north of east and dip north, and in both cases the attitude of the enclosing rocks is somewhat more north of east in strike and more steeply north in dip than that of the veins. As a result of this disposition both veins migrate across their enclosing rocks at a moderate angle in both dip and strike. (In this connection it should be noted that No. 2 vein dips at a considerably flatter angle than its host rock, but has a very pronounced rake to the northeast, effecting the same result as in the Howell vein.)"

Jan 1, 1954