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By Claude A. Jr. Seger

Introduction This paper presents in detailed form the results of settling tests that were published in a few preliminary notes in the April 1949 issue of the Bulletin (p. 166). Carborel is the trade name for sodium carboxymethyl-cellulose and aluminium carboxymethyl-cellulose produced by the reaction of monochloroacetic acid on the alkali cellulose to form an ether. The water-soluble sodium carboxymethyl-cellulose has been known in Europe for several years as sodium cellulose glycolate and has been marketed under several trade names. These cellulose ethers, however, are relatively new in North America, where the name carboxymethyl-cellulose is often abbreviated to C.M.C., or they are referred to as cellulose gum. The particular grade of Carboxel used in the settling tests in the mill of Chesterville Mines, Limited, is the high-viscosity sodium carboxymethyl- cellulose known as Carboxel H.V. It is a white, fluffy powder and is hygroscopic, although not deliquescent. Carboxel solutions in water are colourless, odourless, and resistant to beat and light. They are stable to alkalies, but are precipitated by acids when the pH is reduced below 4.0, and also by solutions of soluble lead, iron, copper, aluminium, and chromium salts. Solutions of Carboxel exhibit the properties of hydrophilic colloids.

Jan 1, 1949

By Jessica E. Heuchan

An industry survey has been conducted by the Queen's University Mining Engineering Department of 30 Canadian mining organizations to determine how effectively newly graduated mining engineers meet the needs of the industry. The principal objectives of the survey were to evaluate, and thus provide focus on change for, curricula being taught at Canadian mining engineering schools in service of the industry's needs; to provide feedback on current industry expectations; and to reinforce contacts with the industry as a means of providing future collaboration. A strong focus of the survey was placed upon industry's perception of the special attributes of engineering hires and applicability of student academic training to meet their industrial requirements. In providing this detailed summary of corporate responses, a clearer understanding of the mining industry's expectations of engineering training at Canadian colleges and universities has been gained.

May 1, 2003

By E. M. Cameron

Reconnaissance radiometric and geochemical data have been obtained for an area on the western shore of Wollaston Lake that includes the Rabbit Lake uranium deposit. The study area is extensively drift cover ed. The geochemical data were obtained by analysis of center-lake sediments and surface waters for a variety of elements and other constituents. The airborne radiometric data comprise measurements of eU, eTh and K obtained with a .50,000-cc NaI (Tl) detector at a mean terrain clearance of 120 m and 5-km flight-line spacing. Uranium in lake sediments and uranium in waters are the most effective geochemical indicators of uranium mineralization; the other elements measured are not notably anomalous. A sample site density of one per 1 8 km 2 is more than adequate for identification of the mineralized area. Because many water samples contain close to or below the current analytical detection limit of 0.05 ppb U, the use of sediments is generally favoured. for broad-scale reconnaissance in the region. Uranium in these lake sediments appears to be little influenced by variations in the organic or iron and manganese content. The most effective radiometric indicator of the mineralization is the eU/eTh ratio. This parameter is less influenced by environmental variation on the ground beneath the flight line than eU alone . The eTh/K ratio is anomalous under the Athabasca Formation unconformity where, in places, the uranium mineralization is localized.

Jan 1, 1977

By J. E. Gillespie

Introduction Mineral wool may be defined as "rock, slag, or glass fibres made by a process of melting and blowing by steam or air, containing a minimum of oil and unfiberized material" (U.S. Bureau of Standards CS 117-44). The earliest production of the material was in Wales, about one hundred years ago. In the United States, the industry daces from 1870 when a plant, using slag as raw material, was established in Greenfield, New Jersey. It was not until 1897, however, that large-scale production was commenced on this continent at a plant in Alexandria, Indiana, which utilized rock from nearby deposits. Today, mineral wool is manufactured in many parts of the United States and Canada, the plants for the most part being in close proximity to deposits of suitable rock or to sources of slag. In the United States there are some seventy-five producers with a total annual capacity of nearly one million tons of wool. In Canada, in 1946, eleven manufacturers produced about fifty million square feet of batt-type mineral wool insulation material. Mineral wool is, perhaps, the most efficient of all heat-insulating materials and, moreover, it is fireproof, extremely durable, and insect- proof. Its high efficiency is due to the very low thermal conductivity of the fibres themselves and to the fact that the produce as marketed contains up to 90 per cent non-conducting air space. Depending on the degree of compression of the fibres in the manufactured product, the specific gravity ranges from 2 lb. to 10 lb. per cubic foot. Products Marketed Following are the principal forms in which mineral wool is marketed: Blanket. - Mineral wool with or without reinforcing on one or both sides, with various types of confining media, all suitably bound together.

Jan 1, 1948

By G. E. Agar

This paper deals with the prediction of locked cycle flotation results from data developed from individual batch tests. A postulate is made that the distribution of material in a separation stage is determined by the chemical conditions and the flotation time and that this distribution can be characterized by split factors which are constants for a fixed set of conditions. With this premise, it is demonstrated that a steady-state balance can be calculated for a circuit. Although the necessary equations can be solved algebraically, a computer program was written that uses an iterative technique to arrive at the steady-state balance. The program is written so that a variety of circuits can readily be simulated. A number of examples are examined to demonstrate the validity of this simulation procedure. The sensitivity of the material balance to changes in the split factors was examined. Data developed from different flowsheets are presented on sulphide ores, on copper-nickel separation and on silver flotation.

Jan 1, 1978

By Taisuke Sakakibara, Shinya Suzuki, Tatsuya Kato, Chiharu Tokoro, Kenichi Muto

Surface complexation using a diffuse layer model were constructed for arsenic (As(V)), zinc (Zn(II)) and silicate (Si(IV)) for aluminum hydroxide in the co-precipitation process. From experimental investigations using isotherms, zeta potential measurement and XRD analysis, it was confirmed that co-precipitation involved not only surface complexation but also surface precipitation. However, surface complexation was major mechanism for As(V), Zn(II) and Si(IV) removal under the target removal level of the Japanese effluent standard. In surface complexation modeling, exchange capacity of aluminum hydroxide was determined from specific surface area obtained from experimental measurement and site density obtained from reference. Surface complexation coefficients were determined by fitting the removal property and sorption isotherm obtained from co-precipitation experiments. These parameters were in agreement with the numerical parameters found by Karamalidis and Dzombak (2010) who reported a database of adsorption equilibrium constants for gibbsite. The surface complexation models constructed in this study were applied to neutralization process of an actual AMD treatment. Our model could successfully represent the pH edges for As(V), Zn(II) and Si(IV) in the neutralization of AMD.

Jan 1, 2015

By J. Doucet, C. Price

In an industrial setting, operational changes are continually introduced, driven by new technologies or changing economics. Because of day-to-day variability, quantifying the impact of these changes based on metallurgical performance requires long trial periods to achieve statistically significant results. Tools and techniques developed by the mineral processing group at McGill University have allowed for direct measurement of process variables (e.g., bubble size, gas and solid holdup). Two case studies are described where direct measurement techniques were used to evaluate: a) a new rotor stator mechanism; and b ), the introduction of a new frother type. Application of these methods has accelerated the evaluation of process changes and improved confidence in results.

Jan 1, 2009

By I. Cotman

Dimensional stone processing has become an important part of the world extractive industry, and today?s total stone block yearly production is estimated to be around 134.000.000 tons and is still growing by an average yearly rate of approximately 20%. In future, the same production will become an important part of the mining industry and presently, in some countries it represents even the main mining output. New environmental regulations, together with landscape and nature conservation requirements, create a number of difficulties in setting up new open pit dimensional stone quarries. As a result, many dimensional stone producers have recently started to apply underground techniques in order to produce the ornamental stone blocks intended for further processing. Underground production of stone blocks requires special mining methods and so far it has not been a cost-effective excavation method for all types of rocks. Presently, this type of stone excavation is generally applied in sedimentary and marble deposits because the rock has small to no mineral quartz content. When starting a new underground dimensional stone mine, it is necessary to analyse the impact of all primary factors which are crucial to set up a technically and cost effective advanced underground dimensional stone mine. The role of physical and mechanical properties of the rock, geological conditions, mineralogical composition, micro-tectonic state of the site, rock mechanic conditions on the site, durability and saw ability of the stone are decisive factors in foreseeing the future methods of extraction. The laboratory research work as well as the field work, is very important in decision-making aimed to choose the future excavation method. Also of equal importance is the serious market research, because it renders the indication of selling price potential. Having obtained the results from both types of research, mining engineers can design the mining methods which optimize financial return to the mine. The practice approved by 15 years of testing in the underground limestone quarry of Kanfanar gives future producers very useful advice and general data to facilitate the process of exploration intended to establish new similar underground quarries.

Aug 1, 2013

By Kevin C. Milne

"The solution of problems associated with development of a sour gas reserve will be of increasing importance in tl1e next few years if gas export is approved •by the National Energy Board. The purpose of this paper is to review briefly the history of the Carstairs gas field, and tCI describe in a general manner the reservoir, and the producing and processing facilities.HISTORYThe Carstairs gas field was discovered in April 1958 when the discovery well, Home Carstairs 10-17, was successfully completed as a gas well in the Elkton member of the Turner Valley formation. Geo-graphic location of the field is shown in Figure No. 1. Note that the field is about five miles west of the town of Carstairs, Alberta, which in turn is about 40 miles north of Calgary. Drilling subsequent to the discovery well resulted in three addition-al producing wells and one dry hole during I.958; two producing wells during 1959; and one producing well and one dry hole during 1960. Thus, seven producing wells and two dry holes have been drilled in the Carstairs field to date.In November 1959 a 12-section block in the Carstairs field was unitized on a surface acre basis. Mean-while, in June 1959, operators in the field executed an ""Interim Plant Agreement"" that provided the money needed to start construction of a joint venture processing plant and gathering system. Construction of the plant and gathering system was completed in February 1960."

Jan 1, 1960

By S. Downing, T. Grammatikopoulos, N. Hoffmann, C. Gunning

"Most deposits display a high degree of geological and mineralogical complexity that can affect metallurgical processing. Therefore, the proper characterization of the ore and gangue minerals requires a multi disciplinary approach combining geology, mineralogy, geochemistry and processing. However, mineralogy to a large extent informs the metallurgical process. Automated methods can be used throughout the mining chain from advanced exploration through to production.In this presentation we discuss actual case studies where automated mineralogy has been applied in a geometallurgical framework at a pre-feasibility to feasibility level. These include examples from a strongly serpentinized magmatic Ni deposit (Dumont) and a magmatic Cu-Ni deposit (Maturi). Mineral speciation and ratios, e.g., chalcopyrite, cubanite, and pentlandite/pyrrhotite are critical to model the Cu-Ni magmatic deposit. In the serpentinized Ni ore, automated mineralogy is used to speciate the Ni minerals into sulphides, alloys and refractory Ni in the silicate matrix.The mineralogical results are linked to the metallurgical test work in order to model the geometallurgical domains. These case studies will illustrate how mineral quantification and improved understanding of inherent mineralogical parameters in relation to metallurgy reduce technical risk in both exploration and flowsheet development.INTRODUCTIONGeometallurgy is a cross-discipline approach combining geology, metallurgy and mine planning (e.g., Dunham et al., 2011). It is aimed to improve the understanding of geological, mineralogical and metallurgical parameters of an ore. Informational gaps among the different disciplines are often apparent. Automated mineralogy is shown in many studies (e.g., Eppinger et al., 2013, Philander and Rozendaal, 2013) to constitute the link between geology and metallurgy. The geometallurgical approach can provide specific data to geology, mining and mineral processing development and plant operations. The scope of the automated mineralogy is to illustrate how mineral quantification can improve the understanding of inherent mineralogical parameters in relation to metallurgy, and reduce the technical risk in both exploration and flowsheet development."

Jan 1, 2016

By E. Ghali, A. D. Bas

There is a lack of electrochemical studies of oxidized gold ores since the majority of previous studies were conducted with sulphidic gold ores. In this study, the influence of agitation and iron oxide minerals, i.e. magnetite, hematite, and maghemite on gold leaching was investigated by means of galvanic and passivation phenomena. Cyclic voltammetry studies of Roasted Gold Ore (RGO) in de-aerated electrolyte have shown one oxidation and one reduction reaction while three oxidation and one reduction peaks were observed with gold electrode. Galvanic coupling results by Zero Resistance Ammeter (ZRA) mode indicated that magnetite showed a negative effect on gold dissolution while maghemite and hematite showed a positive effect, relatively, as a result of higher galvanic corrosion rates. Generally, gold dissolution was found to increase in the initial 15 minutes. Increasing agitation speed from 100 to 400 rpm resulted in higher galvanic corrosion rates for RGO, magnetite, and maghemite electrodes, while 250 rpm was found to be optimum for hematite electrode. Passive products such as silver and iron-oxide were identified by XPS and SEM-EDS analysis, respectively.

Jan 1, 2015

By G. B. Harris

It has long been appreciated that chloride chemistry has a number of advantages over the more traditional sulphate route for both extracting and separating metals. Modern materials of construction, coupled with the development of a more cost-effective and efficient hydrochloric acid regeneration technology mean that chloride-based processes are now more competitive and attractive. Such processing routes are able to recover more of the contained metal values in a feed, including iron in a benign and/or marketable form, and particularly the so-called rare and rare-earth elements which are increasing in demand in our electronic age. These factors, therefore, add appreciably both to the overall economics of a project, but also offer a much more sustainable approach to our dwindling natural resources. Additionally, chloride-based flowsheets can be much more environmentally-friendly, offering practical alternatives to two of the biggest headaches faced by the industry, namely cyanide usage and the generation of red muds. This paper presents a brief theoretical background, focusing on the latest developments of ferrous iron oxidation and the low-temperature, selective hydrochloric acid regeneration process, which is the key unit operation for any chloride flowsheet, and discusses in general the advantages of the chloride approach. Several recently-developed flowsheets, which have been tested at the miniplant level, are presented for gold, base metals, titaniferous magnetites and lead-silver ores wherein the advantages of considering a chloride approach are highlighted.

Jan 1, 2014

By RALPH R. STEA, John H. Fowler

Clay, quartz sand and lignite deposits overlie Carboniferous rocks in central mainland Nova Scotia. Recent evidence indicates that these deposits are fairly extensive. Sands consist of almost pure angular quartz grains. Clays are highly plastic and range in colour from black through grey and blue to mottled red and white. Palynologica/ information dates the sediments as Ear{y Cretaceous, and mineralogical studies show them to consist primarily of quartz, kaolinite and mica. There is not yet enough evidence for detailed stratigraphic description, but sequence and thickness of sediments are known to vary greatly over short distances. Drill logs from Musquodoboit Valley recorded Cretaceous sediments at 168 m thick. Of the three active pits in Cretaceous sediments of central Nova Scotia, two are for silica sand production and are located at Elmsvale and Brazil Lake while a third pit at Shubenacadie produces clay for manufacture of structural clay products.

Jan 1, 1984

By John D. Carr

Introduction The Flin Flon zinc plant operates on what is known as the low density or standard sulphate process, that is, the zinc is carried through the plant solution circuit attached to the SO4 or sulphate radical at a concentration not exceeding 175 grams per litre zinc. The process may be described briefly as follows: The zinc is received in the zinc concentrate chemically combined with sulphur and mixed with many other impurities. The concentrate is roasted and most of the sulphur is burned to a gas, which is discharged from the plant. The roasted concentrate, or calcine as it is called, is leached with a weak sulphuric acid solution so that the resulting leach solution contains a high zinc content but a very small proportion of the impurities. The solution is separated from the solids and is purified further by agitation with zinc dust to remove copper, cadmium, and cobalt. This purified zinc sulphate solution is then pumped to the electrolytic department. The solids from the first leach are again leached, but this time with a stronger acid solution to dissolve all of the remaining zinc which is soluble in the strength of acid available. The solids and solution from the leach are then separated. The solids are stock-piled for further treatment at some future date and the solution, carrying a relatively high amount of impurities, is sent to the first leach, where the chemical action is such that the contained impurities are precipitated as solids. The electrolytic department is nothing more than a large number of electroplating cells in which the zinc is plated on aluminium sheets. Since zinc does not plate tightly to aluminium, the zinc plating or sheet is easily stripped from the aluminium and the sheets are collected to be melted and cast into the standard market bars or slabs. In the electro-deposition cells, the zinc sulphate (ZnS04) is split to metallic zinc (Zn) which plates out, and sulphate (S04) which combines with the hydrogen of the water of the solution to form sulphuric acid (H2S04). When one pound of zinc is deposited, about one and one-half pounds of sulphuric acid are formed. This acid is sent to the leaching section, where it dissolves one pound of zinc from the calcine. The solution is purified and is again pumped to the plating cells. The solution travel forms a complete circuit.

Jan 1, 1935

By A. M. Abdel-Rehim

The present work reports a study of production of thorium concentrate from Egyptian monazite by decomposition of ammonium carbonate solutions containing ammonium thorium and uranyl carbonate complexes. These solutions were obtained from the processing of monazite by alkaline leaching in ball-mill autoclaves, followed by selective separation of thorium and uranium from lanthanides by autoclave leaching of the hydroxide cake obtained with ammonium carbonate - bicarbonate solutions. The separation of thorium and uranium in the form of thorium concentrate from their carbonate complexes was achieved by different methods, including neutralization of solutions at pH = 6.7 by acid, addition of alkali at pH = 11.5, heating of solution at 100°C and processing of carbonate solution with steam under pressure in steel autoclaves. Processing of solutions of thorium and uranyl carbonate complexes in an autoclave with steam causes their decomposition. Complete recovery of thorium 99.8% and 98.4% uranium recovery in thorium concentrate was attained at 120°C and steam pressure 2 atm, within 10 min. Meanwhile, the recovery of lanthanides was low and did not exceed 1.1%. The thorium concentrate produced contains 67.82% Th, 4.6% U and 3.14% REE. All methods achieve complete separation of thorium and uranium from their carbonate solutions, but the first two methods are unfavourable for the industry due to the high cost of reagents and their inability to regenerate the ammonium carbonate. The decomposition of ammonium thorium and uranyl carbonate complexes with steam under pressure is recommended for industrial application for its simplicity and the ability to regenerate the ammonium carbonate.

Jan 1, 2004

By A. R. Chambers

At the 1924 Annual Meeting of the Institute, held in Toronto, the writer presented some notes on the occurrence of salt at Malagash, Nova Scotia, together with a few remarks on the uses of salt. The development of these salt mines has attracted considerable attention to the district, and it may be of interest at this time to call attention to some of the newer uses of salt, and to give a brief account of the genesis of the Maritime salines, As it is not proposed to treat the subject in technical detail, and the paper is written in a lighter vein than is usual in contributions to your Transactions, you will please overlook any variations from a strictly technical method of presentation. The world's supply of salt is obtained in three principal ways: (1) By flooding shallow areas, or pans, with sea water, allowing the water to evaporate naturally by the heat of the sun's rays, and collecting the residue of solid salt. This method is employed, for example, at Turks Island, B.W.I. (2) By mining the rock salt in its natural state, and preparing it for market by a grinding process. This is the method adopted at Malagash, which is the only place in Canada where salt is actually mined. (3) By drilling a hole into an underground salt deposit, forcing fresh water clown the hole, and, after it has become saturated with salt, pumping the brine to the surface and recovering the salt by evaporation. This is the method pursued by the Canadian Salt Company, the Dominion Salt Company, and other producers in Ontario.

Jan 1, 1929

By Tim Watson

Andacollo Hypogene Project ?Overview Project description: Sulphide copper concentrator Throughput:55,000 tpd Location: Approximately 50 km from La Serena Elevation: Approximately 1,000 m ASL Start feasibility study: July 2005 Start of construction: May 2007 Construction completion: December 2009 Final cost(1,2,3):435 Million US $ (1) Excludes third party costs, 220 kV power line (2) Cost is based on a Chilean Peso to US Dollar foreign exchange rate of 535 to 1 (3) Does not include US$40.3 million for the Elqui River Pipeline Project or US$8.0 million for the stock pile cover

May 1, 2010

By CIM Mineral Resource, Mineral Reserve Committee

Industrial minerals are generally considered to include non-metallic minerals, mineral products, or materials that provide raw material inputs for the construction, chemical, and manufacturing industries. They are often relatively low-value and bulky materials that are generally used close to where they are produced; however, some raw materials may be transported hundreds of kilometres to manufacturers and customers (ENDM, 2021). They do not include the metallic minerals, mineral fuels, or gemstones, and are used in industries based on their physical and/or chemical properties (Wikipedia, 2021). In contrast to most metallic minerals, a general distinguishing characteristic of the industrial minerals sector is their general low degree of market elasticity in relation to the market prices and product specifications. The estimation of either a Mineral Resource or a Mineral Reserve (MRMR) for an industrial minerals deposit can be affected to a significant degree by a number of factors that are not typically applicable to metallic mineral deposits. These factors can include such considerations as the particular physical and chemical characteristics of the final product, product quality issues, market size and market access. In some cases, such information may be confidential and proprietary. One of the key challenges of the industrial minerals sector is to define a commonly accepted listing of which types of minerals, materials, or mineral deposits can be considered as industrial minerals (Mining Standards Task Force, 1999). Although definitions for what constitutes an industrial mineral can vary in detail, general descriptions can be found in American Geosciences Institute (2021), Fastmarkets IM (2021), Snowden (2019), SME (2021) and Wikipedia (2021). A brief listing of some of the materials and minerals that are generally considered to be industrial minerals is provided in Table 1. For the purposes of this document, all references to industrial minerals include not only the minerals, materials, and mineral deposits themselves, but also the various commercial products that are derived from these sources.

Nov 19, 2023

By Roger J. Goodman

"Major industrial restructuring, which started to manifest itself in the mature economies of the Western World and Japan in the 1970s, will accelerate in the 1980s and 1990s. Conventional heavy manufacturing industries will continue to lose ground to lighter processing/assembly operations and the new wave of high technology, information and service sectors. The decline in heavy manufacturing has severely impacted on the steel industries of Western Europe, the U.S.A . and Japan.World trade in metallurgical coal has shifted correspondingly, with declining demand in the mature developed countries being only partially offset by large increases in the steel intensity of the newly-industrialized countries (NICs) of the Far East, Latin America and, to a more limited extent, the Middle East and Africa. These trends will be accentuated in future years with direct implications for the distribution of metallurgical coal trade. This paper discusses, in quantitative terms, such changes in the 1980s and 1990s, and examines the implications for, and impacts on, Canadian metallurgical coal exporters.IntroductionThe twenty-year period from the early 1950 s to the early 1970s was characterized by inexorable growth in consumer demand and industrial expansion in most of the advanced countries of the western world. Long- term forecasting during this period typically used linear extrapolation techniques which , despite their simplicity, invariably ended up predicting future demand and production level s with uncanny accuracy. Times have changed!The last decade has been characterized by a n abysmal failure of our economies to respond to simple long-term, linear growth patterns. We appear to have entered a new world in transition, where we can observe a wave of dying or sunset industries reluctantly being submerged by a wave of emerging or sunrise industries.This paper is aimed a t examining the evidence for long-term industrial restructuring trend s. For want of a better word, these so -called, megatrends are then used to predict future demand level s and spatial distribution of steel development and , hence, metallurgical coal trade. It is tempting to correlate the decline in economic activity in the western world with the first Organization of Petroleum Exporting Countries' (OPEC) crisis of 1973. This crisis was probably no more than the straw that broke the camel's back, as the megatrends and embryo s of major industrial restructuring were already evident. Today these megatrends are merely more apparent and transparent than they were ten years ago.While the concept of industrial restructuring is the new economic buzz word, the process was at work, to a lesser degree even throughout the period of strong economic growth of the post-Second World War boom. Many people still remain convinced that our present-day sluggish economy is just part o f the typical , though rather more prolonged, recessionary cycle. Yet, we have always been part of a dynamic economic system and industry throughout history has been the subject of a continuous process of evolution, restructuring and reconstitution . Now the time is ripe to examine the evidence for such restructuring in order to develop coherent policies of adjustment in this transition from one industrial regime to another."

Jan 1, 1985

By G. G. Bowser

PERUSAL of a list of present-day commercial explosives perhaps does not convey a full realization that there has been a great deal of improvement since the original dynamite was discovered nor that, in recent years, great developments have taken place in specialized explosives. This is true particularly of high-explosives for use in metalliferous mining or what is more commonly termed 'hard-rock' mining. Not many decades ago, only two or three types of explosive were avail-'able for commercial use. One was black blasting powder. Another was ordinary nitro-glycerin dynamite in various strengths. Black blasting powder remains with but very little change. Despite its ancient lineage, it is still with us as perhaps the sole explosive in use today which is almost identical in appearance, physical properties, and working ability or execution co the original. Which dynamite the story is different. Its evolution may be likened to that of the dog, nitro-glycerin as first discovered being the counterpart of the wild dog and, like it, dangerous and hard to control. The original dynamite as made by Nobel might then be considered as representing the first domesticaced species. This original dynamite, however, has been 'crossed with other bloods' until one sees now many distinct 'breeds' in the list. Present-day explosives still have the 'bark' and the 'bite', but with control and research have come many improvements; and types have been created which are specially adapted for particular kinds of work. We still have the direct descendant of Nobel's dynamite in the form of an improved nitro-glycerin dynamite. This C-I-L explosive, Polar Dynamite, is no longer the best type to use in the hunt for gold, silver, iron, and other metals. There have been developed other explosives more suitable for chat work. In Canada, such explosives are accomplishing this work effectively, not only where climatic conditions are moderate but through the rigours of our northern winters, with their sub-zero temperatures.

Jan 1, 1938