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By N. Shi, T. G. Joseph

ABSTRACT One-twentieth-scale field trials for conventional and concept dipper designs were compared to mid- and ultra-class-sized conventional dipper performance. Digging effort was used as the performance indicator for comparison. It was shown that linear relationships exist between dipper capacity, suspended hoist load, and peak hoist load. A ratio of conventional and concept dipper performance at the 1/20th scale was then evaluated to allow prediction of the performance of an ultra-class concept design using an independent ultra-class conventional dipper dataset. The outcome indicated a peak hoist requirement of 15.5% less to achieve the same production as the conventional design.

Jan 1, 2011

By Xuewei Lv, Guibao Qiu, Jiaqing Yin, Chenguang Bai

"The iron ore sinter is one of the main raw materials for the blast furnace (BF) process. In the production of iron ore sinter, the cooling speed of the sinter determines its quality. In addition, the heat recovery devices are installed in the cooling machine for energy saving. The cooling parameters like gas flow rate and the size of sinter should be optimized for getting the gas with a higher temperature and a good quality of sinter simultaneously. In this study, the commercial simulation software COMSOL was used to establish a model for simulating the cooling process of the iron ore sinter. Moreover, three different gas flow rate (1.5, 3, 5m/s) and three different diameter of sintered particles (50, 70, 100mm) were investigated with the model. As a result, in certain porosity, a higher cooling speed was achieved when smaller size or larger gas flow rate was used. And lower gas flow rate was beneficial for the heat recovery. The model could intuitively present the exchange of heat between the sinters and air, as well as the flow and temperature fields during the cooling process.IntroductionIron ore sinter plays a great role in iron and steel industry for many Asian countries such as China, Japan and India. As a part of the sintering procedure, the impact of cooling process on the quality of iron ore sinter couldn't be neglected. On the other hand, the massive iron ore sinters which were at high temperature contain extremely large amount of heat. However, it was reported that there's very few of them recovered in China with an average recovery rate of nearly 10.5% at 2004 [1]. Thus, more reasonable cooling procedure should be developed to get high quality product and heat recovery rate simultaneously."

Jan 1, 2011

By Gary E. Sherman

To aid the U.S. Army Corps of Engineers In their Resource Development Navigation Study, the U.S. Bureau of Mines (Bureau) examined the potential for mineral development near ten Alaska port sites. This report presents the results for the first three sites: Bethel, Kivalina (Red Dog), and Omalik Lagoon. The mineral deposits near Bethel are primarily gold and mercury; the nearest deposit being 55 mites away. Because of the expense of constructing and maintaining a road over the poorly drained lowlands, the potential of Bethel as a port site in the near-term is considered to be low. The Kivalina site currently serves the Red Dog mine and has the potential to handle material for similar deposits in the area. Results from a lead-zinc mine model indicate that potential for additional mine development exists in the area. Coal is the major deposit type found near the Omalik Lagoon site. Due to environmental constraints, development of a large-scale mine producing coal for export is considered unlikely. A small-scale coal mine model was used to examine the feasibility of producing coal for regional use. This alternative may be feasible but would require conversion of heating/generating equipment in the area.

Jan 1, 2011

By Kretschmar. U. H.

Fieldwork in the Meguma of Nova Scotia and Archean equivalents shows that bedding-parallel quartz lode gold veins (LVs) commonly occur at the top of graded elastic sequences. We define a "gold cycle" (GC) by analogy with Bouma turbidites and show that most "shear zones" and "lamprophyres" correspond to the upper pelagic-pelitic (E) division. We describe GCs from Archean Chester Twp, ON; Elmhirst, ON; Bourlamaque, QC; "intrusions" and interpret them as crystal tuffs and tuff-breccias. Extensive early Archean pyroclastic volcanism is implied: the genesis of trondjhemite-tonalite-granodiorite (TTG) rocks must be re-examined. The geopetal nature and asymmetric alteration of LVs indicates genesis from sea-floor hydrothermal vents. Textures suggest that often quartz was deposited as a gel. Vent geometry (fracture, point source or diffuse seep), bottom topography and vent spacing is reflected in wade-thickness plots. GC facing directions survive metamorphism. The Bourlamaque batholith was a flat-lying sheet of quartz-feldspar-hornblende crystal tuff, and isoclinal folding has repeated one or more gold-bearing horizons. Syngenesis clarifies and simplifies LV formation with major implications for models. Exploration becomes more cost-effective. Basin analysis, whole rock geochemistry, ore lens geometry and vent spacing can be used.

Jan 1, 2011

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

Refractory copper ores (CROs) in central Africa contain copper minerals that are locked up in a micacious solid matrix or associated with carbonate, sulfide and phosphate minerals. Several researchers have reported that the recovery of copper from CRO material by an acid-leaching process is not economically feasible, due to the presence of excess gangue-acid-consuming minerals such as calcites, dolomite, asbolane and iron oxides. Since the proportion of acid-insoluble copper (CuS) is about 28% of total copper and total free sulfur is extremely small, sulfide flotation was considered unfavorable. Consequently, hundreds of millions of tons of CRO material have been stockpiled specifically at the Nchanga Mine of Zambia. In terms of copper distribution in CRO material, a significant portion of total copper exists as carbonates (39%) and oxides (17%), while 28% of the copper is acid-insoluble (CuS). The rest of the copper is in the form of carbonates (16%) and (hydr) oxides (17%). This means that only about 72% of total copper is recoverable through the non-oxidative acid-leaching process. In this study, batch leach tests were performed on CRO solids (d95 = 95%) to establish the gangue acid consumption values at different feed pH values and to evaluate the leaching characteristics of copper, manganese and iron within the CRO material. Subsequently, continuous leach tests were performed on CRO solids (106 um, 80% passing) using optimum leach conditions derived from batch tests. This paper aims to show that sustainable copper recovery can be achieved by selecting leaching conditions whereby gangue acid consumption (GAC) values become significantly small and the final concentration of manganese and iron in the leach solution are appreciably low.

Jan 1, 2011

By M. Massinaei, M. R. Yarahmadi, S. Zeidabadi, M. Oliazadeh

"Although the majority of new flotation column installations continue to be for cleaning or recleaning, an increasing number of flotation projects are specifying columns for roughing or scavenging duties. NICICO has recently installed flotation columns operating in rougher, cleaner and re-cleaner circuits at three new copper concentrators; Miduk, Sungun and Sarcheshmeh. Miduk is probably one of the unique operations that use flotation columns in a rougher circuit. The Miduk rougher circuit comprises five CISA parallel columns. The rougher concentrate constitutes 88% of final concentrate and reports to concentrate thickener. The rougher tailings are scavenged with ten 50 m3 mechanical cells. The scavenger concentrate is then reground and cleaned in three 3.2 m columns in parallel. The cleaner tailings are scavenged in six 50 m37mechanical cells. The cleaner tailings along with the rougher scavenger constitute final tailings.In Sarcheshmeh, the cleaner concentrate is re-cleaned in a column. The column tailings are sent back to the cleaning circuit and the concentrate is reported to the concentrate thickener.This paper reviews performance details of the flotation columns utilized in rougher circuits at Miduk and compares their metallurgical performances in an industrial scale with columns at cleaning circuits for copper flotation. Practical limitations for applying the flotation columns in rougher circuits will be discussed in details.INTRODUCTIONThe use of flotation columns has grown rapidly since the first successful commercial application at Mines Gaspe, where columns were used in a cleaning circuit to float molybdenite. Early applications of columns were restricted to replacing or adding final cleaning stages in existing circuits. Columns can achieve superior cleaning as compared to conventional cells due to their ability to support a large froth depth and the use of water for washing froth. Wash water travels down through the froth and crosses the pulp/froth interface, replaces the entrained particles reporting to the froth from pulp and improve the concentrate grade."

Jan 1, 2011

By D. Preece

The mining and oil industry employs techniques such as geologic mapping, core drilling and electromagnetic and potential field techniques to explore for new deposits. Since new discoveries of major near-surface ore bodies are becoming progressively rare and since traditional exploration methods are unable to resolve ore bodies deeper than about 500m, high-resolution seismic reflection techniques show great potential for exploration to much greater depths down to almost 3km.

Jan 1, 2011

By Mikhail D. Ageev

The paper concerns with some questions of Autonomous Underwater Vehicle (AUV) control system design, which allows a motion at rough undersea terrain. The AUV advantages reveal itself completely during exploration of such objects as seamounts and reefs area. These objects are characterized by steep slopes (30 degrees and above) and chaotic situated obstacles (rock debris, pinnacles, escarpments). Uses of other technical facilities for operating in such formations are difficult, dangerous or impossible. These regions take an interest due to the presence of iron-manganese crusts. Modern AUV can estimate density of mineral by means of still camera or video recorder. For this reason the vehicle has to move with the distance of 3-5 meters from seabed. Under such conditions micro- and mesorelief presents a considerable danger for AUV. The AUV can bypass underwater obstacles in the various ways. However, in any case AUV motion will be characterized by intensive maneuvering on various speed (from 0 up to 1.5 m/s), circular change of tractive force vector and, hence, a circular flow about the hull. So, AUV is equipped with the propulsion system, which provides free modes of motion. AUV control system (CS) has tri-level structure to allow a motion in a rugged seabed terrain. According to the generally accepted categorizations, CS includes execution, coordination and strategic levels. The strategic level contains the goals of AUV mission. Obstacles avoiding and route choice are realized by means of simultaneous maneuver in vertical and horizontal planes. Sonar system is used for data acquisition about obstacles. It consists of a few echo-sounders with fixed directivity pattern. The route choice algorithm operates at two lower levels of CS. Basic (?reflex?) functions of spatial motion are realized within the execution level and considered in the paper. The choice of motion modes is carried out at the coordination level of system. All accessible navigating information (the data from flight sensors and from multichannel echo-sounder systems) is used for this purpose. In addition the bypass of characteristic types of obstacles is carried out with the help of basic motion modes combination. The modeling results of bypass of various typical obstacles, and also their combinations are described in the paper.

Jan 1, 2011

By Bill Dershowitz

Consider a deep gold orebody with grade of 4 g/t (0.11 oz/st). At the time of this writing, with gold prices at historic highs, it could be a good, but not great, prospect. But if it is a vein deposit, and those veins are 200 g/t (5.8 oz/st), it would be significantly more attractive if there was a way to produce directly from those veins, leaving the rest of the rock in place. [Figure 1 The red around each of the four injector wells shows areas of high pressure, where the lixiviant fluid is pumped into the rock mass, with orange and yellow indicating dissipated pressure. The black lines indicate some of the fracture pathways through which the lixiviant, with absorbed metal, flows toward the central recovery well where low pressure is indicated in blue. Lixiviant is pumped out through the recovery well. Image courtesy of Golder Associates.] There is a way to do this, in situ leach (ISL) or solution mining. It has been a viable commercial technology for more than five decades.

Jan 1, 2011

By Wayne Bell, Matthew Andriese, Shuqian Xie, Jiann-Yang Hwang, Zhiwei Peng

"Pyrolyzed carbons are generally known as good microwave absorbers and their dielectric properties still remain to be fully explored. In the present study the dielectric properties and dielectric polarization-relaxation phenomenon of a typical activated carbon was investigated. The experimental results indicate the complex permittivity is highly dependent on temperature and frequency. The decrease of permittivity with increasing temperature from room temperature to ~100 °C is probably ascribed to the release of the water vapor adsorbed on the surface of activated carbon, and the variations of permittivity with temperatures between 100 °C and 450 °C in the frequency range of 300 MHz to 3000 MHz are mainly attributed to the decreased relaxation time of dielectric polarization.IntroductionPyrolyzed carbons have been identified as excellent microwave absorbers owing to their high dielectric and electrical loss under microwave irradiations. Among them, activated carbon continues to attract more and more attention from researchers. Due to its special physical properties, the production, modification and regeneration of activated carbon with the assistance of microwave have been widely studied over the last few decades [1-6]. However, only few attempts have been applied to explore the dielectric properties of such materials due to the complexity and variability of their organic precursors and activation processes [7,8]. In order to shed a light on this problem, a typical sample, Norit® A Supra USP powdered activated carbon, was adopted to perform dielectric characterization, which may provide useful information for its wide application in the fields of purification, energy (hydrogen) storage and so on."

Jan 1, 2011

By Bern Klein, Randy Blaskovich, Reem Roufail

"Morphology is a tool that is rarely used for mineral breakage mechanism evaluation. Ground particles are typically assessed for their size distribution. They are also visually analyzed using image analysis. However, image analysis is not a comprehensive evaluation of the particle surface texture. It evaluates particle’s size parameters such as area, diameter, and perimeter amongst other features. On the other hand, morphology analysis takes the particle assessment to another level of detail. Morphology analysis evaluates particles’ roundness, elongation and angularity that would indicate the degree of roughness of the particle. According to Roufail and Klein (2009), rougher surfaces are generated due to breakage along grain boundaries – intergranular breakage. Mill operation, particularly mill speed, dictates the dynamics in the mill. Stirred mills are known to break the particles via abrasion under standard operation. However, if the dynamics of the grinding media in the mill are changed, the particles could be more exposed to impact and compression loading that would lead to a different mode of breakage.In this paper, the effect of material properties and mill operating conditions on particle morphology will be studied. Hard non-sulfide versus soft sulfide minerals are compared, namely quartz and galena, respectively. Extreme mill speeds are tested covering the range of 1000 to 2000 rpm for a 4-litre Netzsch (ISA) mill. In addition to particle size distribution, micro-analysis is executed in the form of morphological analysis using a tested manual roughness point counting technique.INTRODUCTIONGrinding in general and stirred milling in particular are processes that are used to break particles to liberate metal-bearing minerals for further separation downstream. The energy required to achieve the target particle size versus maximum possible liberation has been studied intensively and it is usually the breaking point for the grinding system chosen in a process flowsheet. Operating conditions are dictated by the energy consumption. Becker et al. (2001) related different forms of energy such as input, specific, volume/mass specific energies to stress intensities and final product fineness. Other research studies focused on energy input in a stirred mill (Zheng, Harris and Somasundaran, 1996)."

Jan 1, 2011

Beatrix Gold Mine, a deep-level gold mine in the Free State province of South Africa, has the highest methane emission rate of any gold mine in the country. Methane is emitted from underground sources intersected during mining operations and is liberated into the general mine atmosphere. The total methane emission rate for the mine is of the order of 16001/s and the South section of the mine emits approximately 10001/s of methane gas. The mine has a history of gas accumulations which have led to a number of underground explosions. Following the last explosion in 2001 and the subsequent investigation, a number of recommendations were made. Two of these were to consider extracting the underground mine methane to render the mine atmosphere safe, and to declare hazardous locations that require special operating procedures. A number of such workplaces have now been declared at the South section of the mine. Methane gas is a potent, explosive greenhouse gas whose contribution to global warming and climate change is 21 times higher than that of carbon dioxide. To reduce its inherent danger and to mitigate its global warming impact, a carbon credit project under the Clean Development Mechanism (CDM) of the Kyoto Protocol has been developed and implemented, the aim being to capture and destroy the methane at Beatrix mine. The mine has constructed an extraction system to capture and extract 400 (Is of the methane. Percentage methane (per volume) of the gas intersected at source is 85%, with negligible concentrations of other hydrocarbons and water associated. The mine contracted the services of Group Five to design and construct the flare and ancillary equipment on surface, and Promethium Carbon was contracted to assist with the carbon¬-related aspects, approval framework, and administration of the project. A number of design and construction challenges had to be faced to extract and transport the gas effectively to the surface of the mine as the emitters are approximately 3 600 m away from the mine shaft at a depth of 860 m. Further considerations were the requirements for the type of column to be used to transport the methane gas, the pressure loss over the system, the safety systems needed to address the risk factors involved in the transport of the methane gas, and a suitable pumping system to extract the gas to the surface. The system operates under negative pressure provided by two blowers on surface delivering the emissions to a flare capable of burning off 450 8/s of methane gas. In this paper a number of benefits for the mine are discussed. These include, but are not limited to, the removal of approximately 55% of the total volume of methane gas from the general body of the air in the geographical areas of the mine where the methane gas is emitted into the atmosphere, and reducing the risk of methane-related incidents. A further benefit of this project is the mitigation of the global warming impact of the methane gas and the reduction of the mine's carbon footprint by approximately 25%. This project could also assist in alleviating the energy shortage being experienced in South Africa by means of the planned generation of 4 MW of electrical power, utilizing the methane gas, as a second phase of the project.

Jan 1, 2011

By F. Sanchez, A. Mejias, C. Frias, G. Diaz

"Crude zinc oxides are the major source of secondary zinc and are produced from fuming processes like Waelz kilns. The impurities of crude zinc oxides make difficult their processing in primary zinc refineries due to mainly high chloride tenor. Washing with sodium carbonate is a costly operation and chloride removal efficiency is not good enough, so further purification steps are required. The crude zinc oxides are easily treated using ZINCEX™ technology based on leaching, solvent extraction, and electrowinning. The ZINCEX™ process is commercially available and is designed to be a perfect barrier for metallic impurities and halogens, allowing selective zinc extraction in mixed chloride and sulfate leaching solutions. Other valuable components as lead and silver can be efficiently recovered from the leaching residue using PLINT technology in chloride media. Silver is recovered as silver cement and lead is precipitated as pure lead oxide or carbonate, which can be smelted at low temperature.IntroductionZinc is a fully recyclable metal and at present approximately 70% of the zinc produced worldwide comes from primary zinc while 30% originates from secondary materials. Nowadays, the zinc recycling rate is continuously increasing mainly through galvanized steel scrap processing, and crude zinc oxides are the major source of secondary zinc [1]. Secondary zinc oxides are obtained from fuming processes like W aelz Kiln, Rotary Hearth Furnace or Primus Furnace. Waelz is the dominant technology accounting for 80% of total crude zinc oxides production worldwide. In the Waelz process, steel dust is mixed with solid fuel reductant (coke breeze) and pelletized. It is then fed to the kiln and heated to a reaction temperature of l ,200°C. In such conditions, zinc, lead, and other non-ferrous metals are vaporized into the flue gas together with chlorides and alkaline metals. Mixed oxides are drawn from the kiln with the process gases and separated to produce typical crude zinc oxides [2]."

Jan 1, 2011

By Jean-Sébastien Kroll-Rabotin, Éric Climent, Florent Bourgeois

"Falcon concentrators are enhanced gravity separators designed for concentrating fine and ultrafine slurries. The Falcon UF model is unique in that it is dedicated to beneficiation of ultrafines, one key feature being that it does not make use of any fluidisation water. In a former study, we investigated the physical mechanisms that govern the transport of ultrafine particles (in the range 10 to 80 µm) inside Falcon UF concentrators, and concluded that separation efficiency is governed by differential settling. Initially, we derived and published a predictive model of the partition function under dilute conditions. The present paper proposes an extension of the initial model to concentrated ultrafine suspensions for application to industrial scenarios. The paper discusses how hindered settling has been added into the initial model to account for solid concentration effects. The modified model is tested against experiments carried out with a laboratory scale UF Falcon concentrator from dilute conditions up to 30 vol%. A good agreement between measurements and model predictions is obtained, which confirms that our hypotheses about the physics of separation inside a UF Falcon separator remain valid even at high concentrations.INTRODUCTIONThe Falcon concentrator is a fast spinning bowl that is fed at its centre of rotation. It uses centrifugal force to separate particles that are transported inside a thin liquid film that flows upward along the inclined wall of the bowl (McAlister and Armstrong, 1998). Due to differential settling, dense and coarse particles are concentrated inside the bowl whereas light and fine particles are rejected with the overflow stream. The fast rotation speed of the bowl yields high centrifugal force several hundred times the attraction of Earth. Despite the thinness of the liquid film (between 100 µm and 1 mm with a Falcon L40) where separation takes place, the Falcon concentrator can treat high flowrates (up to 30 L/min). At the bottom of the bowl, an impeller transmits the bowl rotation to the feed, which drains upward by centrifugal force as soon as it hits the base of the spinning bowl (Figure 1)."

Jan 1, 2011

By H. J. McQueen

Pressure welding is a solid state joining technique that depends on bringing the parts into sufficiently close contact that inter-atomic bonds are achieved. Pressing is more effective at elevated temperatures where plastic flow causes the asperities to collapse; improved application conditions are derived from hot-work research to clarify temperature and strain rate dependence of hot strength and ductility. The substructure evolution systematically studied in hot working to determine dynamic recovery or recrystallization is applied to clarifying that developed in welding. The various processes are affected differently by work-piece geometry and final shape requirements. In addition to pre-cleaning of the surfaces, the plastic flow helps disperse the remaining oxide layers as was originally exemplified in blacksmith hot forging of layered sword blades and in bellldie welding of wrought iron tubes. The presentation critically compares the utility for various materials and configurations of simple pressure, ultrasonic application, diffusion, explosive, rotary and linear friction and friction-stir processes. Diffusion bonding (primarily Ti) with light cleaning, low pressure, little distortion in protective furnace atmosphere contrasts strongly with the heavy upsetting in friction welding, or complex alloy mingling and substructure variations in friction stir joints.

Jan 1, 2011

By S. Glen

Cyanide management practices on modern gold plants are becoming more onerous, due to environmental pressures, particularly for signatories to the International Cyanide Management Code. Operations are therefore seeking to reduce levels of weak-acid dissociable (WAD) cyanide reporting to spigot discharge as well as to any eventual discharges from the tailings storage facility (TSF). Current gold industry standard processes primarily include the oxidation of cyanide by means of sodium meta-bisulfite (SMBS, or SO2) with air, Caro&apos;s acid (H2SO5) or hydrogen peroxide (H2O2). These processes require the transport and usage of expensive oxidizing reagents, along with the safety and environmental issues associated with these corrosive and toxic chemicals. Maelgwyn Mineral Services (MMS) has developed the MMS CN-DTM process, which utilizes the Aachen ReactorTM, a high-energy mass-transfer superoxygenation system, in conjunction with an activated carbon-based catalyst and no additional reagents, to increase the rate of cyanide oxidation to cyanate, the thermodynamically more stable form. Testwork conducted at the Maelgwyn Australia testwork facility in Perth Australia is described, at both pilot scale and continuous bench-scale, on a sample of tailings effluent obtained from an Australian gold plant. WAD cyanide is demonstrated to be lowered using the MMS CN-DTM process from an influent of 130 mg/L to the required levels for discharge to TSF (<50 mg/L). The continuous test results showed stable operation over three residence time turnovers. The pilot-scale results demonstrated the efficiency of the process at the reasonably large scales required for engineering cost estimation.

Jan 1, 2011

By Bob Katsiouleris

Having passed through the worst of times for industrial minerals demand, there are signs that the best of times lie ahead. If the downturn was the result of unsustainable economic policy, the path forward has everything to do with sustain-ably meeting the demands of more people enjoying higher standards of living than ever before. Minerals producers must be poised to understand and meet their requirements well into the next decade. Successfully marketing industrial minerals - the building blocks of a growing and increasingly urban world population - will depend on producers? ability to respond nimbly to a rapidly changing and regionally evolving macroeconomic environment. A renewed focus on energy conservation, sustainable agriculture and building practices and consumer demand for products with a smaller environmental footprint will drive product and market segmentation strategies. These trends will not only shape the way industrial minerals producers do business, but also the type of skills and people they will require to run those businesses.

Jan 1, 2011

By William Gleason

While a fleet of 100 t (110 st) haul trucks were busy removing overburden from the open pit mine in the distance, a host of dignitaries, including congressmen and California state representatives, gathered for Molycorp?s official groundbreaking ceremony at the Mountain Pass Mine on April 20. The mine, recognized as arguably one of the richest rare earths deposits in the world, is at the center of Molycorps? strategic ?Mine to Magnets? plan. It aims to secure America?s future supply of rare-earth-dependent technologies by developing a strong domestic rare earth industry. Molycorp identifies rare-earth-dependent technologies as those that cannot be produced without rare earth materials. The list of these technologies is long and growing. It encompasses everything from personal electronics and batteries for hybrid cars to permanent magnet generator wind turbines and national defense applications.

Jan 1, 2011

By Robert Hopler

209. Nitro-glycerine is produced by the action of nitric and sulphuric acids on glycerine, and is a heavy liquid of oily appearance, of specific gravity about 1•6, varying from colourless when quite pure to a yellow or brownish yellow. It is of a very sweet taste, and without odour, and is an active poison. Mere handling of it will in most persons induce sickness and headache. It explodes when heated to about 360° F. or from shock, but in small quantities it ignites and burns with some difficulty by the mere contact of flame.

Jan 1, 2011