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By D. A. Cowen

Toll and custom treatment of base metal concentrates have been performed for decades as mines and concentrators are developed distant from capital and, energy-intensive smelting and refining facilities. Commercial treatment terms have been developed and refined for over a century, and are negotiated taking into account a complex array of quality and economic factors. Treatment of third-party concentrates in the South African platinum industry is a comparatively recent development, brought about by the opening up of mineral rights and operations being developed that are smaller than the critical size required to sustain capitalization of smelting or refining plant. Published commercial terms have not been demonstrated to reflect the complexities and subtleties of base metal concentrate markets. This paper outlines some key elements and parameter ranges of base metal concentrate treatment contracts, and applies similar principles to typical Merensky and UG2 platinum group element (PGE) concentrates to determine potential value distribution between the mining and treatment parties in tolling arrangements.

Jan 1, 2012

By P. D. Wilson

The Province of British Columbia covers 382,000 sq. mi., about 250,000 sq. mi. of which have not been prospected. In fact, the coast country and the islands are so heavily timbered and the surface covered with so thick a mantle of soil, muskeg, and, over broad areas, glacial drift, that prospecting and even trail breaking are extremely difficult. It is only along the coast or stream channels, or above the timber line, or where snow or rock slides have scoured the surface, that rock outcrops can be found. Glaciers nestle in many of the cirques and fill the valleys in the higher ranges. Great ice sheets and perpetual snow persist in certain localities, thus reducing the exposed areas worth prospecting. Almost the entire country has been subjected to intense glaciation, so that the conspicuous oxidized outcrops of orebodies typical of the southwestern United States and Mexico do not exist and surface bodies of enriched or oxidized ore are rare. With few exceptions, the mines1 of the Province are working primary ore. Development, have proved that some of these orebodies are large and important, although usually comparatively low in grade. Besides the few mines that have produced most of the minerals, there are many small mines, but their total output is unimportant. Considering the number of mines and prospects and the widespread mincralization, it is strange that no really great mines, comparable in sizc and richness with those in the western United States, have been found. The deposits that most closely approach the status of great mines are

Jan 1, 1923

By P. D. Wilson

The Province of British Columbia covers 382,000 sq. mi., about 250,000 sq. mi. of which have not been prospected. In fact, the coast country and the islands are so heavily timbered and the surface covered with so thick a mantle of soil, muskeg, and, over broad areas, glacial drift, that prospecting and even trail breaking are extremely difficult. It is only along the coast or stream channels, or above the timber line, or where snow or rock slides have scoured the surface, that rock outcrops can be found. Glaciers nestle in many of the cirques and fill the valleys in the higher ranges. Great ice sheets and perpetual snow persist in certain localities, thus reducing the exposed areas worth prospecting. Almost the entire country has been subjected to intense glaciation, so that the conspicuous oxidized outcrops of orebodies typical of the southwestern United States and Mexico do not exist and surface bodies of enriched or oxidized ore are rare. With few exceptions, the mines1 of the Province are working primary ore. Development, have proved that some of these orebodies are large and important, although usually comparatively low in grade. Besides the few mines that have produced most of the minerals, there are many small mines, but their total output is unimportant. Considering the number of mines and prospects and the widespread mincralization, it is strange that no really great mines, comparable in sizc and richness with those in the western United States, have been found. The deposits that most closely approach the status of great mines are

Jan 1, 1923

By F. T. Havard

(Canal Zone meeting, November, 1910.) I. INTRODUCTION. THE present truce in litigation between Western smelting and ranching interests gives opportunity for a summary of the results achieved by metallurgists in condensing fume and de-acidifying furnace-gases. In the absence of complete records of past experiments, there has been a good deal of unnecessary duplication of attempts and' failures. Yet, especially under the recent policy of our large corporations, looking to the economic recovery of the values of by- and waste products, original and, in some cases, effective measures have been developed by American metallurgists. In the case of Bliss vs. the Anaconda Copper Mining Co., the Montana Supreme Court, recognizing the progressive efforts made to render the flue-gases innocuous, and the value to the community of the smelting company's operations, refused to hamper its work, and returned a verdict in favor of the defendant. In the trial, the experimental firms of the company in the so-called "affected region" were proved to be thriving perfectly, showing that immunity was guaranteed to vegetation and stock by the wide distribution of the sulphurous acid gas in the dry air of Montana. Indeed, L. S. Austin has proved that by the time the fume is 4,000 ft.. distant from the stack, the percentage of sulphurous acid has been diminished from 2.28 to 0.00045; and Angus Smith has shown that rain must contain 40 parts per million of free acid before vegetation is affected. The arsenic in the stack-gases is but a very small part of the original content of the ore, of which 80 per cent. and over is rejected in the concentrator and furnace waste-products or recovered in the flues. Nevertheless, neither the peace in Montana nor the armistice

Aug 1, 1910

By H. W. Gillett

MAINTENANCE of membership by the technical so¬cieties and the activity of these societies in spite of the adverse business situation have been noteworthy. This forcibly brings home the fact that industry recognizes that sound technical guidance is well worth its cost. The numerous difficulties and losses due to defects of various kinds arising from gas-metal reactions are now generally recognized and interest in these problems is widespread. The forthcoming A. I. M. E. round-table discussion of gas-metal problems will do much to clarify the situation and will permit us to assay our present knowledge and to suggest the proper direction for profitable future research. "The Age Hardening of Metal" was the title of the annual I. M. D. lecture delivered by Dr. Paul D. Merica. A critical review of the known facts relating to age-hardening phenomena was first given, followed by the presentation of a theory correlating the detailed observations which have been made regarding the mechanism of the hardening.

Jan 1, 1933

By A. J. Kraemer

[During the past several years a great deal of discussion has centered around the question of the permissible limit of sulphur content in fuels for automotive and aviation motors. Under certain conditions of operation, sulphur in motor fuels causes the formation of corrosive substances which attach bearings, wrist pins, and other parts of engines. On the other hand, in making gas¬oline from certain stocks, the gasoline fraction normally contains a relatively large proportion of sulphur compounds. By the generally used processes of reducing the sulphur content, a significant part of the gasoline fraction is lost as motor fuel, and added expenses are entailed for chemicals, labor, and other process costs. This condition has been an economic burden to some refiners of high-sulphur crudes. In some instances the treating losses have been rather severe and the treating costs relatively high, but the data presented in this paper indicate that the reduction of sulphur content of motor fuel is a problem to a relatively small number of refiners and of little or no concern to the remainder; in fact, more then 90 per cent of the 153 samples analyzed passed the Federal specification requirement, which limits the sulphur content to 0.10 -nor cent. 3 This report is based upon the results of an examination for sulphur content, Doctor test, copper strip corrosion, and color of the samples collected during January, 1930, for the twenty-first semiannual gasoline survey of the Bureau of Mines. The results of the gravity and distillation tests of the survey were published as Report of Investigations 2995. The numbering of the samples given in this report is the same' as in Report of Investigations 2995; for example, No. 25 of this report is the same sample as No. 25 of Report of Investigations 2995.]

Jan 1, 1930

By S Amor, A Beasley

This paper provides an example of how industry can respond to the implementation of new regulatory approaches to mining risk, health and safety by adopting a robust, practical, software-based approach to the management of risk accountabilities in terms of competence, experience and suitability for obligations and responsibilities, as required in Queensland Coal Mining operations due to the introduction of Recognised Standard 22 (‘RS22’; Resources Safety and Health Queensland, 2021). Based on the authors’ experience from working with several Qld mine operations, it offers a snapshot of the experiences, approaches and reservations faced collectively by industry as a result of the introduction of RS22. Several challenges exist within the detail of RS22, leading to varied interpretations, implementation strategies and overall compliance between mine sites. Arguably the single biggest challenge identified has been how to find a balance between compliance and practicality – considering cost, operational interruption, available pathways for delivery of competence, ongoing compliance and value adding to the business operations and people. Software-based solutions are increasingly being relied upon to address the introduction of new regulatory approaches and the significant administrative load placed on mining operation Site Senior Executives (‘SSE’) due to RS22 means this case is no different. This is further complicated given the continuous, ongoing changes with the site management structure witnessed by the authors across each of the mining operations as a result of continuous changes to personnel, the site risk profile and an overall mining industry uncertainty of how to respond to RS22. The stringent reporting/notification requirements under legislation compounds this further. The approach put forward by the authors is a well-considered rationale and approach to the application of training and skilling; and equally how to ‘future proof’ the coordination of site training needs around changes to the Management Structure, the Risk Register, skilling processes and succession planning. A brief investigation of other legislative frameworks concluded this approach would likely meet or exceed expectations of jurisdictions across Australia and overseas, making this a highly flexible approach for establishing a competent Management Structure to provide safe systems of work.

Apr 16, 2024

By A. R. Miller

A fuel cell locomotive incorporates the advantages of its competitors, namely catenary-electric and diesel-electric units, while avoiding their disadvantages. It possesses the environmental benefits, at the vehicle, of an electric locomotive but the higher overall energy efficiency and lower infrastructure costs of a diesel locomotive. The natural fuel for a fuel cell is hydrogen, which can be produced from many renewable sources or via nuclear energy, and thus a hydrogen-fuel cell locomotive will not depend on imported oil. Hydrogen produced from renewable primary energies or nuclear energy would provide a totally zero-emissions vehicle, that is, with zero carbon in the energy cycle. A project partnership among Vehicle Projects Inc of the USA, and South African partners Anglo American Platinum, Ltd, Trident South Africa, and Battery Electric, has designed and is launching a series of five prototype fuel cell-powered mine locomotives.

Jan 1, 2012

By Ron Ketterling

We will discuss electronic and paper record keeping, what works and what doesn’t. We’ll review record keeping in light of those five sub-committees: Audit, Awards, Constitution, Ethics and Planning. You’ll come away with concrete steps you can use to improve your record keeping processes

Feb 1, 2020

By Jerry L. Taylor

Utah Power & Light Company is an electric utility serving approximately 1.8 million people in Utah, Idaho, and waning. In order to supply coal to fuel power plants, Utah Power & Light awns three mines in central Utah. Planning for these mines is aided by a computer program developed by the staff mining engineers. This program, when supplied with the pertinent seam and mining configuration data, calculates the time to mine each section. This allows the planning engineer to estimate accurately the time required to extract pillar sections or develop longwall panels. The program's greatest benefit, however, is its ability to allow the engineer to examine quickly, different combinations of possible mine layouts to determine the most efficient plan. Computer aided mine planning has been used at Utah Power & Light Company since 1979, and has significantly improved the accuracy and quality of mine planning.

Jan 1, 1983

By Martin Hertzberg

In this Bureau of Mines study, an equation is derived for the limit burning velocity for divergent, spherical propagation from an ignition kernel of radius, r: (Su)e = ( ) . For flame propagation into a preexisting, stretching velocity gradient of magnitude dv/dx, the limit velocity is (Su)e = (a dv/dx)1/2. These formulations are shown to be equivalent to the fluid dynamic concepts of Damkoh1er, Kar10-vitz, and Markstein. Existing data for the b10woff limits of flames are shown to give excellent agreement with those concepts provided that proper account is taken of two dilution effects: composition dilution caused by entrainment and velocity gradient dilution caused by flow expansion. Approximate flow-field solutions are also derived for the unburned gas motion above an upward propagating, spherical flame kernel in buoyancy-induced flows. It is shown that;, the upward hemisphere propagates toward a stagnation plane in a counterflow configuration involving the balance between the combustion force, which accelerates the cold gas upward, and the buoyancy force that accelerates the cold gas downward. The position of the stagnation plane above the upward propagating hemisphere is related to the ratio of the buoyant velocity, vb, to the burning velocity, Suo Extinction of the upward propagating wave occurs by flame stretch in that counterflow configuration when n = Vb/Su begins to exceed the expansion ratio, Pu/Pb' and the wave is blown off by its own buoyancy-induced flow field.

Jan 1, 1984

By Sherwin F. Kelly

NEW trend in geophysics has been uncovered in these depression years, made evident through the thinning cloak of commercial activity, which, in better times, would have completely obscured it. I refer to the increasing use of these methods for geological investigations by federal and state geological surveys. This is a trend that has been gathering momentum not alone in the United States, but abroad as well. Thus, in Poland, the Geological Survey has been playing an increasing role in geophysical work since 1927, and now has- its own geophysical department. The government petroleum producing organization of Argentina has its Geophysical Commission; Brasil boasts a completely equipped geophysical department in its Mineral Production Service; the government of Chile has contracted with commercial companies for geophysical surveys; Peru is planning an intensive program of geophysical prospecting in its petroliferous regions; and Canada has, for several years, cooperated with

Jan 1, 1935

By R. V. Lundquist

The Bureau of Mines made a laboratory study of the amenability of anorthosite rock ( from the San Gabriel Mountains , Los Angeles County , Calif . ) to treatment by the lime soda sinter process for the extraction of alumina . The study was done under a cooperative agreement with the California Division of Mines and Geology . This report presents the results of the investigation , and it includes a review of the geology of the deposit ( 7 ) by Dr. Gordon B. Oakeshott . Interest in the recovery of alumina from submarginal aluminum silicate ores is stimulated by the fact that the domestic aluminum industry depends on imports of bauxite for its alumina requirements . Of the 8.0 million long dry tons of high - grade bauxite consumed in 1961 for producing metallurgicalgrade alumina , only 0.9 million long tons , or 11 percent , was mined in this country . During past years many organizations have carried out research programs to determine if alumina could be extracted economically from such domestic ores as clays ( 3 , 4 ) , anorthosite ( 8 ) , and other silicate sources . Successful alumina extraction is the ultimate objective of the Bureau of Mines program.

Jan 1, 1963

By L. A. Sandbak, Yan Xing

"The purpose of this study is to evaluate the rock mass stability around the tunnels by three-dimensional (3-D) numerical modeling. Complex geological and tunnel features have been included in the model using the software package 3DEC™. Based on the available information on stratigraphy, geological structures, and mechanical properties of rock masses and discontinuities from the underground mine, 3-D stress analyses were performed on various cases with different K0 (lateral stress ratio) values, constitutive models, as well as support systems. Relations between these factors and the distributions of stress, displacement, and failure zones around the tunnels were obtained and discussed. Finally, comparisons between the field deformation measurements and numerical simulations are used as validations for the simulations, helping to determine the appropriate K0 value and material constitutive models for the underground mine.INTRODUCTIONThe case study site is an underground mine in the USA with a monthly ore production between 20,000 and 30,000 tons. The regional geology of the mine is structurally and stratigraphically complex. Rocks in the area include carbonaceous mudstone and limestone, tuffaceous mudstone and limestone, polylithic megaclastic debris flows, fine-grained debris flows and basalts, all part of the Cambrian-Ordovician Comus formation and related dikes. Both the mineralization and faults have general orientations striking N-S to NW-SE with high dip angles. The ore body in the mine has an incline of about 25---45 degrees located in relatively low quality rock; hence, cut-and-fill mining has been used.This underground mine has two vertical shafts used for ventilation, ore hoisting, and for personnel and material transportation. Development drifts were designed and driven to extract and transport the ore, as shown in Figure I. Bolts, mesh, and shotcrete have been applied in this mine for ground control. In order to reach various locations, the tunnel system is designed with different heading directions and inclines, which will be described in detail later. The area selected for modeling is a cubic region including all the tunnels inside the black square (Figure 1)."

Jan 1, 2016

By Bujtor G. J, McMahon D. W

This guide to the understanding of ore reserve estimation is the revised version of a report with a similar title circulated within the CRA Limited (CRA) group of companies in mid-1980. It is the principal result to date of an Ore Reserve Study commissioned by CRA in late 1977.This guide to the understanding of ore reserve estimationis the revised version of a report with a similar titlecirculated within the CRA Limited (CRA) group ofcompanies in mid-1980. It is the principal result to dateof an Ore Reserve Study commissioned by CRA in late1977.The study was prompted by two ore reserve situations.The Zinc Corporation and New Broken Hill Consolidated,Broken Hill, had reached the point of havingto find a replacement 'for their traditional ore reserveprocedure and Mary Kathleen had to admit publicly thatore reserve predictions would not be realized. Thesewere not however the only problems to be looked at. Asmentioned more fully later, other ore reserve situationswere known, or were met during the study, in copper,gold and nickel as well, where poor realization: expectationratios had ranged from embarrassing to disastrous.These made it clear that ore reserve estimation had to belooked at afresh.The fresh look has resulted in a broadening of theconcept of ore reserve estimation from its traditionalpurely computational basis to an approach embracingall the many things that can affect expectation andrealization as essential factors. Hence this guiderepresents a gathering together of what has been learnedand what should be known to all those concerned withore reserves in any of its diverse aspects.The study has been marked"by a number of changesof thinking. At first the aspects that appeared to requireattention were two; recognition that an ore reserve statementwas an estimate, not a precise calculation; and asearch for im improved estimation procedure adapted tolow grade ores with narrow economic margins. Threeyears later the view was that the need was to incorporateinto ore reserve estimation all relevant aspects of theproposed mining operation from choice of a samplingmethod to sales contract specifications.This study is thought to be unique in being frankabout weaknesses in ore reserve estimation and intreating failures not as natural disasters (like drought orflood, which have to be endured) but as potentiallyavoidable. It has led to three principal conclusions.

Jan 1, 1982

By Clayton M. Rumsey

The U.S. Bureau of Mines conducted a mineral resource survey of the Cinder Cones Wilderness Study Area (WSA) (CDCA-239), 10 miles east of Baker, CA, in 1983. The 44,299-acre WSA is underlain by Precambrian granite gneiss, Upper Cretaceous or lower Tertiary Teutonia quartz monzonite, and Quaternary basalt flows and alluvium. This mineral survey included an examination of two volcanic cinder mines, five lode prospects, two volcanic cinder prospects, and reconnaissance sampling in and near the WSA. The seven prospects are in the WSA; the two volcanic cinder mines are adjacent. No mines are in the WSA. In 1981, there were 61 placer and 3 lode mining claims in the WSA. Sample results from two prospects within the WSA contained significant gold and silver values; however, the mineralized rock is of limited extent and no resources were apparent. Alluvial samples taken throughout the WSA contained only traces of gold. Two volcanic cinder cones within the WSA contain an estimated 30 million tons of cinders. There are sufficient cinders outside the WSA to satisfy demand in the foreseeable future. Stone, sand, and gravel deposits are not resources because similar material is closer to markets. No evidence of energy minerals or geothermal resources was found.

Jan 1, 1985

Smoky Valley Mining Company, Round Mountain, Nevada, was the pioneer operation designed for large scale heap leaching of crushed gold ores. It is located in the Big Smoky Valley which stretches 160 km (100 miles) through central Nevada west of the Toiyabe Mountain Range. Gold was first-discovered at Round Mountain, 88 km (55 miles) north of Tonopah, in 1905; and mining in the area included placer operations, which ran from 1946 to about 1960. Smoky Valley Mining Company is a partnership of Felmont Oil Co., Case-Pomeroy & Co., and Copper Range Co., with the latter being wholly owned by Louisiana Land and Exploration Co. In 1969, an option on the Round Mountain property was acquired by Copper Range, and during 1974 a decision was reached to proceed with mine development and plant construction. Ore reserves were reported at 10,537,000 mt (1 1,617,000 st) of 2.09 g per mt (0. 061 oz per ton) gold using a cut- off grade of 0.69 g (0.02 oz). Silver content was approximately 2.4 g per mt (0.07 oz per ton) and the waste to ore ratio was about 1: 1. By the end of 1976 heap leaching was in operation. The ore is a rhyolite tuff, sometimes described as a gold porphyry with highly abrasive qualities but which does not break down into slimes upon contact .with cyanide solutions. Gold is unevenly distributed through the ore but as a whole it is in a very finely divided state. Climatic conditions are extreme in central Nevada. Summers are hot and dry while winters are windy and cold with subfreezing temperatures. Elevation of the property is about 1,920 m (6,300 ft). Precipitation averages 203 mm (8 in.) per year. Until February of 1980, leaching was continued until the temperature reached minus 2ºC (28º F), and about 10 months leaching was the average. Water for the operation is drawn from the Toiyabe Mountains through a 13. 7 km (8. 5 mile) pipeline, originally installed in 1915, or from wells in the valley bottom. The plant requires make-up water at the rate of about 1,500 liters per min (400 gpm). On a schedule of three shifts, seven days per week, the daily output at Round Mountain amounts ,to 12, 700 mt (14, 000 st) consisting of 6,350 mt (7,000 st) each of ore and waste. Ore is hauled with a fleet of 45 mt (50 st) trucks and dumped into the 1,0.70 by 1,650 mm (42 by 65 in. ) gyratory primary crusher located near the pit. The primary

Jan 1, 1981

By D. A. Paice

Direct current electrical systems are used in most coal mines primarily to power the main haulage trains and secondarily to feed other equipment and passageway lighting. Electrical power is supplied from rotary machines or static rectifier equipment and is distributed through the mine by open trolley wires and feeder cables. The rails of the haulageway are used as a current return path. This exposed power distribution system is very vulnerable to conditions which lead to undesired leakage currents and short circuits and, consequently, the possibility of fires or other hazards to personnel. Present techniques and equipment have been utilized in so far as practical to improve the safety of the dc electrical system; however, there still appears a need for further improvement. Because of this need, this program was sponsored by the Bureau of Mines to investigate two specific technical areas related to improvement of dc electrical system safety. One area included the determination of the characteristics of mine electrical systems and their protection requirements and the verification of the adequacy of available protective devices for mine service. Despite the widespread application of industrial protective equipment in mines, there was little detailed technical information available related specifically to the performance of this equipment in service. Our task was not only to develop useful information regarding mine system protection, but also to define and verify the adequacy of the protective devices available. The second area of investigation called for development of a practical technique for detecting low level electrical fault or leakage currents. Conventional protective devices

Jan 1, 2012

"SUMMARYThe K.M.A. reservoir was discovered to be oil bearing at a depth of 3,719 feet on March 11, 1931. Extensive development, however, was not begun immediately, because the discovery well had a low initial daily oil production, and market conditions for oil were unfavorable. Development of the field progressed slowly for the next 6 1/2 years. In the latter part of 1937, a wildcat well approximately 2 miles southwest of the discovery well was drilled on a magnetometer high and completed with an initial flowing production of 2,016 barrels of 43° A.P.I.-gravity oil in 12 hours. Rapid development of the southwestern part of the K.M.A. field was begun immediately and continued until over 700 wells were drilled and approximately 12,500 acres proved oil productive.Because of the large size of the entire K.M.A. field, this report is limited in scope to the southwestern part only, and the discussion that follows pertains to this area only. The closing date for production statistics is August 1, 1949.The K.M.A. structure is a complex anticline having a maximum closure of 250 feet, and the K.M.A. formation is composed of sediments that grade from limestone through sandy lime and limy sand to sandstone with thin streaks of shale. Two distinct members of the K.M.A. formation, zone I and zone II, are oil productive. Core analyses indicate the average porosity to be 16.5 percent for zone I and 16.1 percent for zone II. A relationship was established from core data, which showed the correlative permeabilities to be 42.1 millidarcys for zone I and 39.5 millidarcys for zone II, whereas the arithmetical averages of the permeabilities were 84 millidarcys for zone I and 216 millidarcys for zone II. Connate water saturations were 17.5 percent for zone I and 20.0 percent for zone II. The porosity-saturation method, using a thickness-correction factor, was employed to calculate the volume c 168.1 million barrels of stock-tank oil initially in place in the reservoir. Analyses of the reservoir oilIn that, although the initial reservoir pressure was 1,750 p.s.i., the original reservoir oil was saturated to only 1,300 at which pressure 1 barrel of stock,tank oil contained 525 cubic feet of gas in solution.A serious decline in reservoir pressure during the 2 years of rapid development alarmed the operators and caused them to consider a cooperative pressure-maintenance program. In the latter part of 1939, the K.M.A. Pressure Maintenance Association was organized, and the gasoline plants in the field agreed to process the wet gas and return the dry gas to leases having gas-injection wells. Approximately 27 percent of the cumulative volume of produced gas had been returned to the reservoir by August 1, 1949."

Jun 1, 1952

A new short combined flow sheet including high intensity magnetic separation and flotation for a rare earth ore in Maoniuping deposit, China has been investigated. Massive conclusive results demonstrate, that it is critical to separate the ore by high intensity magnetic separation prior to flotation for tons of slimes and nonmagnetic gangue existing. The vital technological parameters affecting flotation have been studied in detail. Modified hydroxamic acid is an efficient collector for bastnasite flotation because of its high selectivity. Flotation results also indicate high temperature that play an unfavourable role on the recovery as well as the grade of bastnasite concentrate, when the rare earth ore is floated with modified hydroxamic acid and sodium silicate depressant. Bastnasite concentrates, averaging over 65 percent REO at an overall recovery of 82-84% is achieved by the new beneficiation technology. Keywords: bastnasite, REO, magnetic separation, flotation, chelating collector, desliming

Sep 1, 2012