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By Eugene Frey

"INTRODUCTION The Iron Mountain deposits were examined in the summer of 1943 by engineers of the Bureau of Lanes, and a diamond-drilling project was set up under the Strategic Minerals Program. Actual drilling operations, under the supervision of a Bureau engineer, commenced November 9, 1943, and were completed on November 1, 1944. When the Bureau began detailed exploration of the Iron Mountain deposits, the Federal Geological Survey participated. Dr. I. W. Newhouse, of the Survey, and Dr. A. F. Hagner, of the Wyoming Geological Survey, were assigned to the investigation.ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief, analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.With respect to this report, acknowledgment is made to S. R. Zirrmerley and F. T. Allsman, Bureau of Mines, Salt Lake City, Utah, who supervised the work of this project."

Nov 1, 1946

By S. Akhtar

Interstitial compounds of iron, cobalt, and nickel, and their binary and ternary mixtures with silver, gold, palladium, and platinum were prepared and tested as fuel cell catalysts. The first step in the preparation of the interstitial compounds consisted of preparing finely divided metals. This was done either by the Raney method or by reduction of precipitated hydroxides of the metals. The finely divided reduced metals were then treated with carbon-and/or nitrogen-containing gases to prepare their carbides, nitrides, and nitrocarbides. The materials were tested for cathodic activity towards O2 and for anodic activity towards H2, C3H8, NH3, CO, and N2H4 in acid and alkaline electrolytes at 25° to 90° C in half-cell assemblies. Samples of carbided and nitrocarbided INi-lAg-1Au were about one fifth as active as Pt-black in the reduction of O2 in 35 percent KOH solution, whereas the activities of several interstitial preparations exceeded the activity of Pt-black in the reduction of O2 in 12M KOH containing N2H4. Nitrocarbides of x-Fe2C, 3Ni-1Au, and 1Ni-3Au were effective catalysts for oxidizing N2H4 in liquid NH3 containing NH4SCN. Corrosion of the catalysts by electrolytes was severe in many cases.

Jan 1, 1970

By A. Yu. Lein, V. V. Maslennikov, S. P. Maslennikova, I. Y. u. Melekestseva, Yu. A. Bogdanov

Tellurium is a high-tech and also toxic element. This element shows sufficient contents in Fe-Mn crusts and nodules in the modern ocean to be involved in future industrial processes [Hein et al., 2003]. Tellurium minerals and contents are not well recorded in modern and ancient black smoker systems. Tellurides are rarely found in sulfides from the modern oceans [Iizasa et al. 1992; Maslennikov et al., 2010]. The previous common opinion that tellurium is scarce in active seafloor hydrothermal systems can be revised due to the recent discovery of abundant tellurides in chimneys from Brothers Volcano vent site [Berkenbosch et al., 2012]. We found abundant tellurobismuthite, hessite, and native tellurium in chimneys from Su Su Knoll vents sites (West Pacific). So, tellurides can be found in some chimneys but absent in others. The causes of this are poorly understood. These conflicting data create numerous questions and require an explanation. The problem can be resolved by research at different scales including analysis of relevant genetic features of host sequences, systematic textural and paragenetic studies of different types of chimneys, and their rare mineral assemblages. Paragenetic models, compositional analyses and ranges of tellurium-bearing minerals and the physicochemical interpretation of chimney diversity in different types of VMS deposits are the main subjects of our research. The data on tellurides in chimneys from ancient VMS deposits should also be useful to resolve this problem.

Sep 1, 2014

By T van der Meer, A Salokannel, M Martikainen, L M. Nevatalo, J McCulloch

Water use and wastewater management is becoming a focus for many industries around Australia and the rest of the world. Good quality water is increasingly being recognised as a precious resource, and regulations on the bulk storage and discharge of waste streams is becoming more stringent in order to protect the environment, existing water reserves and the communities that use these resources. Components such as heavy metals, arsenic, cyanide, and sulfate from acid mine drainage are some that occur at mining and metallurgical processing sites. Removal of such components can allow safe re-use of these streams, reducing the new water requirements of the process, or else allowing acceptable discharge to the environment. Re-use or discharge of treated water eliminates or reduces the risk associated with storage of large volumes of contaminated water on site.Technologies where a contaminant is selectively precipitated and removed as a sludge are used for many of these treatments. Selection of the best treatment option for wastewater must depend on what is suitable to each site, and consider not only the nature of the contaminant, but also other aspects, including the location and situation of the site, local regulations, cost of reagents, the sensitivity of the local environment and waste sludge disposal options. To outline how an effective and economical solution can be designed and delivered, this paper will present a case study for the removal of arsenic from a site wastewater, from assessment of the problem, selection of suitable technology, design and implementation, to the benefits delivered to the site.CITATION:Salokannel, A, Nevatalo, L M, Martikainen, M, van der Meer, T and McCulloch, J, 2013. Technology selection for removal of contaminants from an industrial wastewater, in Proceedings MetPlant 2013 , pp 531-538 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

The mineral Industry, following the economy as a whole, experienced little growth in 1992. However, with modernized plants, efficient workforces, and lower operating costs, the industry is well positioned to take advantage of possible improvement in the national economy during 1993. In addition to the significant 1992 events highlighted below, important events, trends, and issues within individual mineral industries are addressed in the commodity sections that follow. The value of processed materials of mineral origin is estimated to have been about $310 billion in 1992. The value of U.S. raw nonfuel minerals production in 1992 is estimated at approximately $32 billion, a 3% increase over 1991. The value of domestic minerals production has increased in all but 4 of the last 32 years.

Jan 1, 1993

By Robert A. Elgin

The Leadville mining-district (fig. 1) covers approximately 8 square miles adjacent to Leadville, the county seat of Lake County, Colo. It is famous for its large production of rich ores containing zinc, lead, copper, gold, and silver. Some manganiferous ores also have been produced.

Jan 1, 1949

The optimum cut-off grade policy maximizes the net present value (NPV) of an open pit mining operation subject to the mining, processing, and refining capacity constraints. The traditional approaches to cut-off grade determination ignore the escalation of the economic parameters such as metal price and operating costs during life of an operation, and consequently lead to unrealistically higher values of the objective function. Further, the NPV of a mining operation declines due to the depletion of the available reserves, causing a decline in the optimum cut-off grade, i.e. higher cut-off grades in the early years of an operation and lower cut-off grades during the later years. Hence, low grade material mined in the earlier years may be stockpiled for processing during later years to offset the effect of escalating economic parameters on NPV. This paper demonstrates the combined impact of introducing economic parameters, escalation and stockpiling options into the cut-off grade optimization model. The model promises an enhancement in NPV as illustrated in a case study incorporating practical aspects of an open pit mining operation.

Jan 1, 2011

By Peter Haller

Introduction The impact of the Comprehensive Environmental Response, Compensation, and Liability Act, or Superfund, as well as the Resource Conservation and Recovery Act (RCRA) and their state counterparts underscore the intention of the nation's lawmakers to reduce the risk from hazardous substance to American society. The promises and requirements embodied in these laws, together with their prospects for liability, will continue to have a very substantial impact on decision making in the mining industry. These laws present the prospects for staggering liabilities, often of an unquantifiable nature in terms of time and amount. It is therefore necessary to keep them in clear focus. This is particularly true in light of President Reagan's signing into law the Superfund amendments on Oct. 17, 1986, and in light of the Environmental Protection Agency's (EPA) major policy pronouncement of July 3, 1986, regarding solid wastes from extraction of ores and minerals. This article examines the general trends as well as the specific provisions of these laws in an effort to assess the prospects of liability for the mining industry of releases of hazardous substances into the environment. Hazardous substances vs. hazardous wastes The distinction between the terms "hazardous substances" and "hazardous wastes" is important to appreciate for the purposes of assessing the potential for liability for a mining operation. Hazardous substance is a term that appears in and is defined in the Superfund Act. In Superfund, it is defined by reference to other substances that have been declared to be hazardous under other federal environmental statutes, such as RCRA, the Clean Air Act, and the Clean Water Act. Hazardous waste is a term that is less all-encompassing than hazardous substance, as that term is defined by RCRA. Hazardous substances do not need to be wastes to be considered hazardous for the purpose of Superfund liability. A "release" of a hazardous substance into the environment can bring about potential liability under Superfund. Many mining wastes, even though they are not considered hazardous wastes by EPA under RCRA, have been determined by that agency to be capable of bringing about liability under Superfund if they contain chemical substances, such as the heavy metals copper, lead, mercury, zinc, silver, and others. Therefore, it is not sufficient for the mining industry to be able to answer whether one has hazardous waste at a mining site. That question only goes partway in addressing the potential for liability. The next question is, do one's solid or liquid mining wastes contain hazardous substances that could bring about liability under Superfund? Superfund 1980 law: A review Some provisions of Superfund as it existed before its recent amendments must be considered. The law provides that the owners and operators of mining sites, together with those who transport hazardous substances to such sites, can be held jointly and severally liable for the cost of cleaning up the site. The concept of joint and several liability means that one party, as among many, can be held totally responsible for the costs of cleanup. This is particularly true where the harm done by many parties to the envi-

Jan 2, 1987

By W. G. Park

Long-range projection of demand for domestic crude oil indicates a continued upward movement and accentuates the need for increasing the recovery from known crude-oil resources to supplement expected future discoveries. Consequently, the industry and Government have given special attention to the viscous or heavy-oil deposits because they offer the distinct possibility of large order increases in ultimate recovery. This report presents data pertaining to 150 heavy-oil reservoirs in Arkansas including oil characteristics of samples from 38 of these reservoirs. To January 1, 1967, about 600 million bbl of heavy oil has been recovered from the 150 reservoirs in 63 oilfields; however, about 4.5 billion bbl, or 88 pct, of oil remained in the ground. Of prime importance is that much of this heavy-oil resource is in reservoirs having characteristics considered favorable for thermal-recovery operations. Data for the thermal projects initiated [thus Ear are presented in individual field discussions. Also discussed is the t crude oil supply-demand situation in the State.

Jan 1, 1969

The Calypso geothermal field, mapped by the R V Sonne (cruise SO-135) in 1998, includes four main sites, the Northern Vent Area (centred on 37¦ 36.7'S, 177¦ 06.2'E, area 1.5 km2), Central Vent Area (37¦ 39.4'S, 177¦ 05.2'E, 1 km2), Southern Vent Area (37¦ 41.7'S, 177¦ 06.0'E, 1 km2) and Mercury Vent Area (37¦ 41.3'S, 177¦ 07.3 'E, 0.5 km2). Hydrothermal activity at the vent sites is controlled by minor, sub-parallel NE-trending normal faults. Gas bubble trails (C02) and shimmering hot water vent from fractures and joints between large blocks of silicified volcaniclastics and in depressions in the sediments at the base of these outcrops. Measured maximum vent temperatures are between 180¦C and 201¦C. Venting fluids are at, or just below, boiling for water depths of 200 m. Rock samples recovered by dredge from the sites include massive anhydrite, clay-altered pumiceous ash, silicified volcaniclastic sediments and volcaniclastic breccias cemented by sulphur. Clay-altered samples, dominated by randomly interstratified illite-smectite and accessory chlorite, indicate formation environments of 70¦C to 90 ¦C. Native sulphur is abundant throughout the samples. Fine-grained (<1 mm) disseminated pyrite and vein pyrite occurs in the clay-altered pumiceous volcaniclastics and argillites. In the Southern and Mercury Vent Areas, fine-grained orpiment, realgar and cinnabar have deposited in the sandy matrix of volcaniclastic breccias. Amongst the cinnabar, small (<2 mm) beads of native Hg formed on the surface of several rocks following their recovery. These samples also contained abundant light hydrocarbons, which coat the rocks with an oily sheen.

Jan 1, 1999

By Carl R. Peterson

[In lTI n,v und I'gr'oun nllnin~ Opt'I'ali n' the high . t cost is the loading and I 3ulage of t tln-of -D"'line ot'. 01' hauling costs can be r duced signifi-cant\v with the us ~ (r \) >It corn'e)'OI' " a COnlTllOn pl'acti c i.n coal and other s 0 t'L rn I n r' a l III i, n e , '. Jf 0 vel s i z ' () f' e can bee 1 i 11.11 tl ate I rH'i 0 I' lO C n v e . in g, ]

Jan 1, 1976

Compagnie Miniere Esperance (CME), a mining company based in French Guyana, operates a gold primary ore body in open pit. The ore is processed through crushing, grinding and gravity separation. Tailings are stored in a ?fine? pond. Analyses of the fine ponds proved a residual gold grade sufficient for a chemical treatment. However, direct cyanidation would require a too large installation, regarding the local conditions (accessibility, supplying and rainforest meteorological conditions). It has been then decided to test the feasibility of a pre-concentration using flotation. Lab tests have been carried out by SGS Lakefield (Canada) in March 2007, which proves the technical feasibility. Therefore, CME asked Caspeo to: ? Carry out an on-site flotation pilot campaign. ? Design an industrial flotation circuit. The tailings reprocessing will contribute to a better tailings management and a dry up of the gold resource, limiting the risk of illegal mining after remediation of the CME site. CME MINE The Esperance gold mine is located in French Guyana, in the vicinity of several gold deposits as Omaï, Rosebel or Camp Caïman, holded by Iamgold and Newmont. These main gold deposits are located on the figure 1. Esperance was put into operation in the early 90?s. The first years were devoted to the mining of alluvial gold in the gravel of the Esperance Creek. Since then, operation was led in the primary gold deposit. Annual production is on average 254kg for a total production in fifteen years of 4300kg. Geology Esperance deposit is located in the greenstone belt of the Guyana Shield. Mineralization is in tectonic contact between sedimentary basin of Maroni and a granitic massif. Clastic series, composed of conglomerate and lamina sandstone, overlie a volcano-sedimentary basement (series called "Paramaca"). The area is strongly folded by shear movements, resulting from granite deposit. Gold is in interlacing quartz veins intersecting the clastic series. Gold is present in association with pyrite. Other elements, as silver or arsenic, are in negligible quantity. Exploitation The Maroni River is the only access to the Esperance mine. Only the saprolite and a part of the transition rock are extracted in the open pit. Excavation works are done using shovels Hyundai 450 (4 units) and haulage works using articulated dumpers Terex TA35 (4 units). These two sorts of equipments are presented figure 2. Mill The mill is composed of crushing and grinding processing plants. After gravity concentration, both plants produce tailings that are stored in two ponds: the first pond contains coarse product which segregates the particles crushed to 2mm upstream and settled clays downstream; the second pond contains the fine product made of particles ground to 200µm. These two ponds, bordered by dams and diversion canals, are located on former alluvial sites of Esperance Creek (see figure 3). [ ] The CME mill is currently producing gold concentrate, with a global recovery of about 67%. The ore is crushed by one jaw crusher and two hammer crushers. The ore then passes through a Knelson KC 48 gravity concentrator, producing a first gold concentrate. The

Jan 1, 2009

By Richard E. Danell

"Blasting is a principal step in the surface mining process for breaking and, in the case of overburdencasting, moving rocks and minerals. As many surface mines are coming to the end of theiroperational life, blasting can once again play an important role through the earthmoving operationsrequired to rehabilitate the minesite. Since blasting is such an energetic and destructive process, itis difficult initially to envisage its use in rehabilitation. However, blasting has found applications inmany civil engineering projects aimed at rehabilitation, including well digging, channelling and soilcompaction. For surface mine rehabilitation, the main purpose of earthmoving operations is toproduce a stable landfonn that will sustain revegetation. In particular, blasting can be applied toreducing the slope of steep walls left by quarrying and open pit mining through a modified form ofthe overburden casting technique. Blasting can also be applied to breaking up pit floors andbenches to speed and improve revegetation of these areas (subsoiling)."

Jan 1, 1994

By P Williams, S Flynn, R Birchfield, R Simcock, R Toft, P Comeskey

Direct transfer, or community translocation, comprises salvage and replacement of intact æsodsÆ of vegetation together with underlying soil. It has been applied to New Zealand mine sites restoration of native grasslands, wetlands, scrub lands, and forest. It is an equivalent technique to æinstant lawn or tree gardenÆ, commonly used in urban landscaping. Two to six m2 scoops of vegetation, with up to 0.7 m of soil attached, and including root plates of trees and shrubs, are relocated from stripped areas ahead of mining to sites prepared for restoration. Direct transfer uses hydraulic excavators or face shovels and dump trucks, possibly with the aid of bulldozers and other earthmoving machinery. The main advantages of direct transfer, compared with sowing or planting systems for mine site restoration, are the recycling of plant and soil materials which were often wasted by burying under overburden materials, a significantly faster revegetation process, and restoration of the whole ecosystem (plants, animals, birds, invertebrates, and microbes). The main disadvantages are higher costs of stripping and dumping, a greater degree of machine operator skill required, and scheduling becomes critically important. To illustrate the key principles, this paper gives examples of successes and failures of the technique for a variety of New Zealand mining situations. Direct transfer has been successful for a range of communities, from fern wetland and sub-alpine tussock grasslands to 5 m-tall beech forest under storey and seral shrub land, and from temperate to sub-alpine climates. Successful examples show both rapid recovery of indigenous vegetative cover and conservation of habitat for birds and invertebrates. Failures have resulted from excessive death of plants because of inadequate soil salvage depths, acidic leachates, inappropriate handling of stripped sods by inexperienced machinery operators, or prolonged drought conditions immediately following relocation. Change in plant species composition has occurred where clumps of vegetation are too far apart, or shifted plants were too small - in both cases invasive weeds have smothered the original vegetation. Changes in hydrology can also have significant impacts. Our experience indicates that the advantages of direct transfer far outweigh the disadvantages and is now used as the preferred restoration method, where practicable, at mines where it has been trialled.

Jan 1, 2000

By Richard D. Smith

The Bureau of Mines evaluated the emission control methods, including the capital investments and operating cost, necessary for further reducing lead levels in ambient air at the Glover, Herculaneum, and Buick smelter-refineries in Missouri and the East Helena, MT, smelter. The U.S. Environmental Protection Agency (EPA) has proposed more stringent lead in ambient air standards than those currently in effect. This report presents theoretically achievable lead emission reductions and estimated capital and operating costs. Lead emission inventories theoretically can be reduced from 1985 levels by 2,421 lb/d at the three Missouri operations by containing and filtering fugitive emissions within structural enclosures and baghouses. The aggregated capital and operating costs in 1986 dollars using conventional environmental and workplace technologies are estimated to be $250,014,100 and $18,507,800, respectively. Estimated total incremental cost is $0.063/lb as refined lead. Additional regulatory costs attributable to Occupational Safety and Health Administration (OSKA), U.S. Department of Labor, workplace standards are included since proposed environmental controls may otherwise degrade workplace conditions. Continuous drossing is evaluated as an alternative to conventional OSHA controls. Substituting continuous drossing for conventional work- place technology results in an estimated aggregated capital and operating costs of $258,344,800 and $15,719,600, respectively. Estimated total incremental cost is $0.062/1b as refined lead. For comparison, the average open market price of refined lead during the first quarter of 1986 was $0.184/lb.

Jan 1, 1987

By Kenneth E. Hay

Researchers from the U.S. Bureau of Mines conducted a field study to assess the safety of remotely controlled mobile roof supports (MRS) in a retreat pillar mining operation, Data were collected to provide the Mine Health and Safety Administration with criteria needed to develop guidelines for MRS use and to determine if precursors could be identified that would alert miners to imminent roof falls. Two test sites at which two different support methods-MRS's and posts were used and were monitored to obtain information on entry stability. Pressure transducers and string pots were installed on all four MRS's to obtain loading and displacement information. and roof bolt load cells. sonic probes, extensometers, and survey targets were installed in the surrounding entries to obtain information on ground behavior. Results showed a larger increase in roof bolt loading and roof movement when MRS's were used, especially in the intersection area. Roof bolt loads in the entries showed decreases in load when the MRS's were set and increases up to 11,1 kN (2,500 lbf) when the MRS's were unloaded. Unloading of one MRS in a pair did not significantly increase load on the other. MRS's I and 2 usually had the higher loads, with these loads increasing as the pillars on each side were being mined. MRS 3 normally had lower loads than I and 2: however, it also experienced some very high loads when in the last position near the pushout. MRS 4 usually had the lowest loads, primarily because it was located near the solid pillar that was not being mined.

Jan 1, 1995

By Alan J. Lutenegger

Some years ago, a method was developed to incorporate a grout column around square-shaft helical screw-piles and anchors to increase shaft buckling resistance under compression loading. An additional benefit of this grouted shaft is to increase the load capacity in both compression and tension, depending on the geometry of the lead helical section and the soil conditions. Because of the unique construction procedure, the contribution of the shaft to the total capacity has largely been unknown. The behavior of grouted shaft helical anchors in clay was investigated by performing full-scale axial uplift (tension) load tests on a series of anchors installed at the University of Massachusetts Geotechnical Test Site. In order to isolate the contribution of the grouted shaft to the total load capacity, anchors were installed with a wooden dowel connection between the lead helical section and extension sections on three of the four anchors so that only the shaft resistance would be measured during the load tests. The grouted shafts ranged in length from 10 to 30 ft (3 to 9 m). Initial tests were performed approximately 5½ months after installation. Nearly four years after the initial tests were performed, the tests were repeated to evaluate any significant change in capacity with time and/or repeat testing (preshearing). The soil conditions at the site are presented along with the load-displacement curves for both the initial and repeat teats and a discussion of the analysis of the results. Repeat load tests showed an increase in capacity from the initial testing, however the percent increase was not the same for all depths. The results demonstrate that considerable shaft resistance can be developed in clays from the grouted shafts as might be expected. Depending on the L/D ratio of the shaft and the contribution of the lead helical section, at working loads the shaft capacity can dominate the behavior.

Jan 1, 2011

By Stratton-Crawley R., G. E. Agar

"A study has been done of the scale-up of laboratory bench-scale flotation to continuous plant circuit performance. It was found that the impellor speed and the air flow rate influenced the results and in this case extreme values of these operating variables were required in order to reproduce the plant rougher results in the laboratory. Despite the experimental uncertainty introduced by these extreme values, it was demonstrated that the plant performance could be predicted and experimentally reproduced with bench-scale tests.IntroductionThe mineral processing industry relies heavily on batch flotation testwork to design flowsheets, evaluate reagent s and compare various types of ore. The batch tests are generally regarded as being directly comparable within themselves, but quite often they relate poorly or not at all to continuous circuits. Obviously this dilemma generates considerable uncertainty with wide-ranging ramifications. One of the manifestations of this unfortunate situation is the commonly expressed opinion that ""it may work that way in the laboratory, but it will never work that way in the plant"".In a previous publication, a method was described whereby the results of batch bench-scale tests could be used to simulate a locked cycle flotation test series. The work to be described here is a continuation of that investigation with an extension to the simulation of an actual plant circuit. It would have been preferable to progress from laboratory batch data to a continuous pilot plant and then finally to a full-scale plant operation. However, because that possibility did not present itself, an attempt will be made to show that the performance of an existing plant circuit can be successfully simulated from batch data. The success of the procedure can be judged by the agreement among the plant results, a locked cycle test and the predicted results based on batch tests."

Jan 1, 1982

Hydraulic fluid power systems are advantageous whenever power output must be accurately and safely controlled. The load movers, cylinders, jacks, rotary actuators and hydraulic actuators in these systems can be made to smoothly and accurately start, stop, reverse, hold position or move steadily under heavy and variable loads or torques. Because hydraulic systems are simple, compact, reliable, and low cost compared to other power methods and because they can deliver controlled power anywhere on the machine to which a hose can be routed, they are a pan of almost every type of machine found on a coal mining section. Some of the functions they perform are positioning drill booms, driving drill pots on roof bolters, positioning curter booms, raising, lowering, and swinging conveyors, driving conveyors on continuous miners, raising, lowering, and applying sustained loads to longwall roof supports, and advancing the face conveyor and roof supports in longwall mining operations.

Jan 1, 1982

By L. BENEDICT

COMMENTING on the report of the latest Royal Commission for India, the September, 1926, issue of the National City Bank's monthly letter states, among other things, that "The decision of the Royal Commission is against the proposal for a gold coinage, but in favor of placing the silver coins and paper currency now redeemable in silver on a gold basis." Also, it quotes the following from the Royal Commission's report: The essence of the proposal * * * * * is that the ordinary medium of circulation in India should remain as at present the currency note and the silver rupee, and that the stability of the currency in terms of gold should be secured by making the currency directly convertible into gold for all purposes, but the gold should not circulate as money. It must not circulate at first, and it need not circulate ever. In this connection it may be stated that during the last one hundred and fifty years or so unsuccessful attempts have been made by the governments of different nations of the world to devise a plan or plans by which gold and silver could be used concurrently for money purposes and, particularly, as standard money; such, for example, as bimetallism, which, of course, is impracticable. But, since none of such plans has been adopted generally it is logical to conclude that their proponents did not shape them so as to conform to the basic principle of standard money, or else political issues were deemed to be dominant, or, perhaps, it was partly due to each.

Jan 1, 1926