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By R. Minnitt, C. Morgan, D. Fourie

The problems associated with outliers and their adverse effects on resource estimation in deep level South African gold mines are presented, and solutions suggested in available literature are reviewed. Traditional Witwatersrand type outlier capping uses the 99th percentile grade as the upper limit, a somewhat blunt approach. The occurrence of high and low grade areas in mining operations and the estimation of resources using geostatistical techniques require that the assumption of stationarity be upheld. Honouring the stationarity of data requires that mining areas be subdivided into appropriately sized and spaced domains. In order to overcome high-grade conditionally biased block estimates, the overly strong influence of extreme grades is mitigated by using naturally occurring grade sub-domains, by identifying outliers within the grade sub-domains, allocating relevant capping limits, and weighting them in a post-estimation process to. Rather than applying a capping value across a domain it applies a maximum cap based on the extreme value and its range of influence; the method also ensures that relevant capping occurs even in lower grade sub-domains. The proposed method for capping outliers recognises that metal contained in high grade chip samples should not be over-capped, and based on the grade of surrounding samples. The post-processing method of capping outliers does not interfere with the kriging equations. The method is simple, elegant, and can be easily applied. An advantage is that the output from the kriging process is not overwritten, allowing for comparison between original kriging results and post-processing results.

Sep 1, 2021

By V. Oberholzer

The presence of fines (particles smaller than 6 mm in diameter) causes hydrodynamic problems in gasifiers and therefore it is of great importance to minimize the amount of fine coal in the feed. This serves as motivation for understanding coal?s breakage mechanisms, which could lead to the ability to predict the generation of fines. The aim of this project was to simulate the pulsating effect of the conveyor belt in order to investigate factors influencing the breakage. Results indicated that an increased initial particle size had an increasing effect in the amount of fines generated. Weathering had an insignificant effect on the breakage of coal. To conclude, a breakage model was developed to describe the rate of breakage out of the top size when a combination of two breakage modes is present.

Jan 1, 2009

By Y. R. Murthy, S. Angadi, A. K. Bhatnagar, S. K. Tripathy, L. O. Filippov

Dolomite is an essential raw material for the refractory industry, a flux in the iron and steel industry and also for the extraction of magnesium metal. Generally, particle size reduction, screening and classification are used for the preparation of the high-grade sized material for different applications, whereas low-grade fine fractions are not utilised. These fines or low-grade overburdens are dumped at the mine site for future utilisation, which creates environmental issues along with inadequate space management. In the present investigation, a detailed study was carried out to decrease the silica content of the low-grade dolomite fines from Gomardih , India, containing 28.6% CaO and 20.1% MgO along with 8.3% silica. Different process flow sheet options were evaluated with a combination of dry classifier, wet classifier, gravity concentrators as well as flotation. Different process variables were assessed along with mineralogical characterisation to optimise the process for efficient rejection of siliceous gangue minerals. Results indicated that dolomite, calcite and quartz are the major mineral phases present in the ore along with other minor minerals. It was concluded that two-stage flotation was an effective process for the reduction of silica up to below 1% after grinding to a particle size below 212 μm. A process flow sheet with a combination of gravitation air classifier and flotation can produce a concentrate with silica content below 4.5%. Keywords: Dolomite, flux, dry classification, flotation, characterisation, beneficiation

Jan 1, 2020

By P. W. J. Delport, E. Du Toit

Investing in a mining venture can be risky and stakeholders need transparent, unbiased reports to understand the Mineral Resources and Mineral Reserves a mining company holds. Readability and textual choice can be used consciously to manipulate perceptions, or it can be done unconsciously. This exploratory study investigates the readability and textual choice of supplementary Mineral Resources and Mineral Reserves Reports of companies listed on the Johannesburg Stock Exchange. The results indicate that narrative manipulation occurs in these reports through word choices that make the reports difficult to read, as well as specific narrative selections. This reduces the informational value of the reports. The results of the study will be useful to various stakeholders, such as mining company management, investors, investment specialists, financial analysts, and even employees and the general community, who all use these reports to make important decisions. It is also useful for the preparers of the Mineral Resources and Mineral Reserves Reports, Competent Persons, and other technical specialists to be aware of readability and that certain textual choices can affect the interpretation of these reports. It is recommended that bodies such as the JSE and the SAMREC and SAMVAL Code committees consider adding a plain language requirement to regulations, guidelines, and codes to ensure transparent, unbiased, and objective reports.

Mar 1, 2021

By H. von Blottnitz, B. E. Isheloke

Mining is a significant economic activity in most Southern African Development Community (SADC) countries, and mineral beneficiation has been identified, and controversially discussed as one of the possibilities for industrialisation. With many member countries being economically too small to muster the human and financial resources which beneficiation requires, the recently adopted Regional Mining Vision (RMV) envisages interventions at a regional level. An opportunity arose to ask industry role players to what extent the SADC appears to support regional beneficiation policy interventions undertaken by member countries, and what the challenges are in undertaking beneficiation regionally, as a complement to, or substitute for country-specific beneficiation policies. Twenty-five semistructured interviews were conducted with experts from SADC member countries during the 2019 Mining Indaba. Participants were divided on whether beneficiation should be carried out nationally or in the SADC region. While beneficiation could support value-keeping, key challenges were found to be infrastructure development (i.e. energy, water), scarce skills, access to technology and related costs, but also lack of free trade and movement. We submit that a more integrated beneficiation strategy for the SADC region, as is being developed through the RMV, would indeed be relevant in the future. Keywords: Mineral beneficiation, regional integration, beneficiation policy interventions, African mining vision, mining, SADC

Jan 1, 2020

By I. Druce, C. Li, T. Qu, J. Dong, W. Y. Xinchao, V. Nkuna

CITIC Heavy Industries has a large installed base of grinding equipment throughout Africa in different configurations, including high-pressure grinding rollers with ball mill and semi-autogenous ball crusher. The total installed power of CITIC’s mills exceeds 430 MW. In this paper, we compare several typical grinding circuits of copper in Africa with about 15 kt/d throughput based on ore properties, process selection, equipment sizing, and key equipment capital and operating costs. Actual operating performance is also introduced. The comparison for the following mine sites provides a general reference for the selection of copper grinding circuits with this approximate throughput: Kamoa-Kakula Copper Mine with high-pressure grinding rollers with ball mill circuit, and Deziwa and Sicomine Copper-Cobalt Mines with semi-autogenous ball crusher circuits

Jan 1, 2023

By M. Pawlik, N. Ghaffari Touran

The interactions between apatite and hematite were studied through zeta potential and stability experiments, for this paper. The zeta potential measurements were conducted in both background electrolyte and mineral supernatants. The difference in electrokinetic properties of minerals in the presence and absence of supernatant was explained in terms of the dissolution of minerals and the subsequent readsorption of dissolved species at the mineral-water interface. The stability measurements in individual and mixed mineral systems were also performed to identify the extent of interaction between apatite and hematite upon their direct contact. The results from stability measurements in individual and mixed mineral systems indicate that there is an interaction between apatite and hematite. Based on the results, the implications for the apatite-hematite separation process were discussed. Keywords: Apatite, hematite, dissolved ions, stability, zeta potential

Jan 1, 2020

By E. Chisakulo, M. W. Songolo, E. K. Chanda

Zambia’s mining industry has undergone various phases of mineral royalty changes since privatisation. Unlike many analyses that relied on subjective probability, this study employs the cut-off grade and mineral royalty model relationship to investigate how changes in mineral royalties impacted the net present value and cut-off grades of Zambian copper mines between 2008 and 2022. The results showed that net present value decreased by 10.39%, 6.13%, 9.69%, and 6.13% for Barrick Lumwana, Kansanshi, Nkana–Mopani Copper Mines, and Mufulira–Mopani Copper Mines, respectively, while First Quantum Minerals Trident’s net present value increased by 3.40%. Reductions in NPV correspond to higher government revenue, whereas the increase for FQM Trident reduced government revenue. For cut-off grades, returns increased by 0.42%, 1.20%, and 0.42% for Barrick Lumwana, First Quantum Minerals’ Trident, and Kansanshi, respectively, showing how portions of the Zambian copper orebodies accrued to investors, with a corresponding reduction in government revenue. Conversely, reductions of 0.24% and 0.38% for Nkana–Mopani Copper Mines and Mufulira–Mopani Copper Mines indicate that a share of the ore reserves accrued to the government, reducing investor returns. These findings demonstrate that mineral royalty adjustments redistribute economic value between investors and the government, affecting both profit margins and operational decisions. Despite these distributional effects, all projects remained economically viable. The findings underscore the need for an optimal mineral royalty framework that equitably balances the economic value of mineral resources between investors and the state

Jan 30, 2026

By E. Matinde

Poor phase separation and fine dissemination of the desired components within congruous slag phases are key challenges limiting the recoverability of values from slags by conventional beneficiation methods. Slag microstructure conditioning is a pragmatic approach to increasing themvalue-in-use of discard slags, especially when integrated with the broader smelter infrastructure. Although not yet tested on oxide slag systems, this paper explores the potential application of magnetohydrodynamic principles to the crystallization behaviour of bulk slags. Integrating the slag microstructure conditioning infrastructure to the existing smelter infrastructure is key to unlocking the economic value of slags because it is most economic to condition the properties of molten slag directly after tapping. A new business model that integrates smelting units to transversalmeconomic activities, such as cement production and suppliers of construction aggregates, canmsignificantly increase the circularity of metallurgical slags.

Oct 9, 2024

By D. F. Malan

This paper provides an overview of the concepts of citations and journal impact factors, and the implications of these metrics for the Journal of the Southern African Institute of Mining and Metallurgy (JSAIMM). Two key research literature databases publish journal impact factors; namely, Web of Science and Scopus. Different equations are used to calculate journal impact factors and care should be exercised when comparing different journals. The JSAIMM has a low impact factor compared with some of the more prestigious journals. It nevertheless compares well with journals serving other mining sectors, such as the Canadian CIM Journal. The problems associated with journal impact factors are discussed. These include questionable editorial practices, the negative impact of this concept on good research, and the problem of a few highly cited papers distorting the journal impact factor. As a consequence, there is growing resistance to the use of journal impact factors to measure research excellence. The San Francisco Declaration on Research Assessment is a global movement striving for an alternative assessment of research quality. As a recommendation, the Editorial Board of the JSAIMM should adopt a pragmatic approach and not alter good journal policies simply to increase the journal impact factor. The focus should remain on publishing excellent quality papers. Marketing of the Journal, the quality of the published papers, and its open access policy should be used to counter the perception that journals with high impact factors are better options in which to publish good research material.

Sep 1, 2022

By R. Uwaoma, A. Goosen, R. Matjie, K. Mphahlele, J. Bunt

Coal properties that are associated with wear and damage of grinding equipment during pulverization prior to combustion were investigated. A South African Highveld feed coal and its beneficiated fractions were crushed to <1 >0.25 mm particles for the grindability tests. These particles were milled and screened into <75 μm and >75 μm fractions, which were analysed by different techniques to establish a correlation with the conventional Hardgrove Grindability Index (HGI). The <1.5 g.cm-3 float fraction, which contained 93 vol.% (mineral matter free) total -macerals,9% kaolinite, and had the lowest HGI (57) (hardest to grind) was pulverized for 15, 30, 60, and 120 minutes for particle size distribution analysis. This analysis indicated that the content of <75 μm particles increases with increased grinding time. The >1.9 g.cm-3 sink fraction, with the highest HGI (76), 44% kaolinite, and 20 vol.% total macerals, was ground easily to generate the highest proportion of <75 μm particles. Based on higher correlation coefficients (R2 = 0.77–0.91), the ash yield, mineral matter, petrographic composition, and fixed-carbon have significant effects on the HGI. Conversely, the inherent moisture and total sulphur (R2 = 0.48–0.62) have only minor effects on the HGI. Results from this investigation could be implemented in the preparation of a suitable pulverized fuel with little equipment wear, as well as utilizing mineralogical and petrographic compositions. Finally, the effect of microlithotypes and maceral types in South African feed coals on the HGI should be investigated in further pulverization and grindability studies.

Jul 5, 2023

By L. Morgan, M. Le Roux, Q. P. Campbell

Dry coal processing is becoming increasingly favoured as a fine coal beneficiation technique. The decline in suitable good-quality coal, as well as the ongoing decrease in usable process water, makes dry beneficiation of the fine coal fraction even more crucial. Dry fine coal beneficiation is a relatively young process with most of the methods still in the developmental phase. Additionally, many of the dry processing options available are better suited for coarser (+6 mm) and easy-to-beneficiate coal. Air winnowing for fine particles has been established in both agricultural and pharmaceutical industries, which indicates that the method can be used to separate smaller particles on a density basis and therefore, may prove effective in the coal industry as well. A proof of concept study was conducted using both computer-based simulations (which do not form part of this paper) and physical experiments. The initial winnowing unit consisted of a closed box with a horizontal air stream flowing through the top section. Coal particles were injected into the air stream and displaced horizontally across a distance (x), depending on the particle size and density, thus actuating a separation based on these two parameters. For this study particle sizes of 6, 4 and 2 mm were used all with a density ranging from 1200 kg·m-3 to 2000 kg·m-3. The simulation in Star CCM+ confirmed the findings of the mathematic behavioural model and provided a virtual representation of the separation using streamlines and particle tracks. The coal tests prove that size separation can be achieved at an airflow velocity of 21 m·s-1 and the density cut-point can also be predicted by using the prediction matrices constructed as part of this study. The results show efficiency values (EPM) of 0.11 and 0.09 at density cut-points of 1400 kg·m-3 and 1500 kg·m-3 respectively. The data obtained from the study indicates that air winnowing can be used to separate fine coal particles based on both size and density. However, in order to achieve an efficient density separation, a narrow size range is required. With some improvements to the model, simulation, method and design, the separation efficiency can also be improved. The next phase of testing will include the upscaling of the process to a demonstration plant, optimising the separation unit and testing the method on different qualities of coal. Keywords: Dry processing, fine coal, winnowing, simulation, tracers, demonstration plant

Jan 1, 2020

By C. Birch

"The purpose of this study was to establish the impact of discount rates on cut-off grades for narrow tabular gold deposits as characterized by the goldfields of the Witwatersrand Basin in South Africa. There are various methods available for determining the cut-off grade, from simple breakeven calculations to sophisticated software packages that consider a variety of inputs to optimize the cut-off grade. For this study a simple financial model was created in Microsoft Excel® that links the ore flow, block listing, and the cash flow. This allows the cut-off grade to be optimized considering how the cost of capital and chosen discount rate affect the cash flow.The discounted cash flow (DCF) and resultant net present value (NPV) are a widely used valuation method for production properties according to the South African Code for the Reporting of Mineral Asset Valuation (SAMVAL Code). The financial model in this study utilizes the Solver function, as well as simple Microsoft Excel spreadsheet formulae to optimize the NPV. Solver was chosen as it is a standard feature in Excel and thus no additional software costs are incurred beyond the basic Microsoft Office suite. For the purpose of this study, just narrow tabular gold deposits of the Witwatersrand Basin were considered. An example of a typical ore block listing, as well as the costing figures, was obtained from an operating gold mine. The results obtained from the study financial model were compared to the current cut-off grades obtained from the mine using their proprietary optimizer program, and were found to be comparable. The methodology utilized for this study thus appears valid.The cut-off grade was optimized considering the cash flow, which includes the variable mineral resource royalty tax, the variable gold income tax, as well as the discount rate. By comparing the resultant NPVs using discount rates of zero, 9%, and 12%, the impact of the discount rate on cut-off grades, resultant life of mine, and average mining grades (AMG) could be compared for the example ore block listing. The South African Code for Reporting of Exploration Results, Mineral Resources and Mineral Reserves (SAMREC Code) does not require operations to state if a discount rate was considered in determining mineable reserves. Mining companies approach the question of applying discount rates in determining their cut-off grades, and thus mine planning strategy, in different ways. Due to the negative impact that optimizing purely on NPV has on the life of mine, some choose to optimize only on profit. Other companies have reverted to utilizing pay limits as their primary grade planning strategy. The calculated cut-off grade is then considered to be another planning indicator rather than a hard determination of mineable reserves."

Jan 1, 2016

By A. Modi, C. Li, R. Kabwit, W. Y. Xinchao, R. Joshi

The KIMIN copper project can treat 1.7 million dry t/a copper-cobalt ore. It has three mills in operation, two using conventional milling in water and the third in raffinate. We introduce the project process circuit and the capital and operating costs of using the raffinate process compared with conventional milling in water. There is a capital saving of approximately 11.5% for major equipment by removing the pre-leach thickener. In addition, it also achieves an annual operating cost saving of USD 2.1 million due to an increase in 49% of acidic raffinate recycled and reduction in lime consumption. The features of CITIC’s new duplex stainless-steel ball mill ,as the key equipment of the system, are also introduced

Jan 1, 2023

By V. Yahorava

Efficient recovery of precious metals from process solutions is essential for improving process economics. Traditionally, precious metals are relatively effectively recovered from waste streams via precipitation or cementation. However, these approaches have a number of drawbacks, including poor water balance, creation of environmentally unfriendly waste streams, and losses of precious metals. Ion exchange technology is an alternative for the recovery of precious metals from waste or low-grade streams. This technology allows the recovery of the precious metals to extremely low levels (micrograms per litre) with relatively high upgrade ratios from the solution onto the resin without major water balance concerns, while the impact on the environment could be minimized or avoided. Research was conducted on the recovery of platinum group metals and gold from different low-grade and waste streams from one of the precious metals refineries in South Africa by means of ion exchange. Various functionalities and matrices (granular and fibrous) of ion exchange materials were evaluated. The results from these studies indicated that in some cases ion exchange could be very effective for the recovery of precious metals, and that the PGM concentration could be reduced to < 1 mg/L. The upgrading ratios of the various PGMs onto the specific fibres were relatively high for the specific streams evaluated, which might in some cases justify incineration of the loaded material instead of stripping and recycling the adsorbent. The cost of direct incineration for one of the waste streams tested would be less than 1% of the value of the PGMs recovered. However, the adsorbent has to be carefully selected and the process design optimized for each specific stream.

Jan 1, 2014

By M. Bueno, T. Chavez Matus, M. S. Powell, S. Michaux, S. Luukkanen

Comminution tests are an essential element in the design of ore beneficiation plants. Many methods have been developed to assess the breakage characteristics of rocks to generate parameters for modelling. However, most of the existing methods are laborious, expensive and require large samples. Consequently, test work has been traditionally conducted with a few representative reference samples. On the other hand, geometallurgical modelling programs require an extensive amount of test work to allow understanding the variability of ore properties within the deposit and establish spatial geometallurgical domains that show the differential responses to mineral processing. Therefore, comminution tests for geometallurgy need to be more efficient in terms of time, cost and sample size. This paper introduces a new testing device (Geopyörä) which is capable of measuring forces and energy applied to rock particles during the breakage process. The new testing method uses smaller samples and can be up to 50 times faster than other commonly used tests in the industry. This paper presents the concept prototype and the preliminary test work results, which have been benchmarked against some of the industry standard tests, such as the JK Drop Weight Test (JKDWT), the SMC Test® and the Bond ball mill test. Keywords: Geometallurgy, comminution, ore breakage characterization, variability.

Jan 1, 2020

By S. M. H. Haddad, M. Saghaeian, R. Hejazi, V. Sheikhzadeha, A. H. Baladastian, A. Dehghani Ahmadabadi

Sulfide impurities in iron ore concentrates play an important role in designing pelletising and steel making plants. Therefore attempts are made to keep the sulfur content of the final concentrate produced by the plants as low as possible. Generally, in the beneficiation process of iron ore concentrate, the removal of sulfur is performed through magnetic separation systems, followed by reverse flotation. The sulfide content of the iron ore concentrates originated from two main sources, including pyrite and pyrrhotite. In this research, in order to compare the floating capability of these two types of sulfide minerals, two iron ore concentrates with different sulfide constituents, pyrite or pyrrhotite, were selected. Reverse flotation tests were done separately on these samples under similar conditions. Process parameters considered for the tests included pH (2, 4, 6, 8 and 10), collector consumption (150, 200, 250, 300 and 350 g/t) and frother consumption (40, 50, 60, 70 and 80 g/t). Potassium Amyl Xanthate (PAX) and Methyl Isobutyl Carbinol (MIBC) were the collector and frother used in the tests, respectively. For modelling and optimising process parameters, the Central Composite Design (CCD) method was applied to the test results. Empirical coded equations were obtained for responses involving weight recovery, Fe recovery, Fe grade and S grade. Finally, comparison of test results revealed that the elimination recovery of pyrite sulfides was far greater than pyrrhotite sulfides, and it was possible to remove 84% sulfur content of the pyrite sample compared to minus 30% for the pyrrhotite sample. Keywords: Reverse flotation, pyrite and pyrrhotite, sulfur removal, iron ore concentrate, beneficiation plant

Jan 1, 2020

By S. Saeed, N. Coulson, P. F. Stewart

"The Mine, Health and Safety Act No. 29 of 1996, as amended, embodies worker self-regulation to advance health and safety in the workplace. An important provision for this is the Right to Refuse Dangerous Work (RRDW). This paper explores worker perspectives about the implementation of RRDW on South African mines against a backdrop of revised guidance in the sector: ‘Guideline for a Mandatory Code of Practice on the Right to Refuse Dangerous Work And Leave Dangerous Working Places’, gazetted in February 2016 by the Department of Mineral Resources (DMR). A mixed methods study conducted at mines (n = 14) included a survey of workers (n = 293), focus groups (n = 6) and in-depth interviews (n = 16). Workers reported a high level of awareness, a positive attitude, and experience of the formal RRDW. However constraints to the formal RRDW meant that informal worker resistance to dangerous work was commonplace. Evidence of informal non-confrontational consultation, cooperation, and collaboration in the event of a dangerous workplace also emerged between workers, and supervisors. The research underscores the importance of the RRDW and worker health and safety representatives to mine health and safety. The revised guidance addresses RRDW implementation gaps, but of concern is the potential partiality towards management interests. IntroductionEnsuring that mineworkers act on their duties and responsibilities for health and safety remains a concern across the globe. Article 13 of the International Labour Organization (ILO) Convention Safety and Health in Mines (176 of 1995) entrenched the Right to Refuse Dangerous Work (RRDW) as an important mechanism through which workers act in the best interests of their own occupational health and safety (OHS) and is considered a cornerstone of worker self-regulation (ILO, 1995). Countries ratifying Convention 176 are under obligation to make this right available to workers through OHS legislation that frames the circumstances, procedure, and protection of workers from discrimination in the event of a formal work refusal. The Convention has been ratified by 31 countries, with South Africa becoming a signatory in June 2000 (ILO, 2000). Worldwide studies show that workers use this right with caution (Hilgert, 2013) and cases associated with work refusal are rarely presented in court (Gunningham, 2007; Cooper, 2013). Rather, in cases of formal notification of a work refusal, issues arising out of this are addressed either in the immediate workplace or through the site OHS system and/or at industrial tribunals or similar mechanisms (Harcourt and Harcourt, 2000)."

Jan 1, 2018

By C. Dorfling, M. Tadie, M. Tucker

Electrowinning is the final step in the hydrometallurgical production of high purity copper, involving the passage of electric current through an electrolyte and consequent plating of solid copper to form cathode sheets. Key electrowinning performance indicators are the current efficiency, specific energy consumption, yield, and quality of the metal. The high energy demand and associated cost mean that determination of performance indicators is critical during operation, but ‘online’ measurement is impractical due to the nature of the measurements and corrosive environment brought about by acid mist. This research considered the development of a predictive electrowinning model as a shift towards a pre-emptive approach to attaining plant performance data. A steady-state model was created from input variables available in the industry, using a first-principles approach combining mass balances, electrochemical and thermodynamic equations, and property correlations. A circuit diagram equivalent of an electrowinning cell, containing multiple pairs of electrodes, was used as the backbone of the model. The kinetics of each electrochemical reaction were modelled including iron as a major impurity. Losses in current efficiency due to ineffective electrode contact, short circuits, and stray currents were also incorporated. The model was used to predict the current efficiencies for tests performed at varying conditions in a bench-scale electrowinning cell; the average absolute error between the measured and predicted current efficiencies was 3.2%. The model requires a unique parameter fitting approach for each industrial operation; if parameters are customised for specific plants, the model will be a useful tool to predict performance and can aid the development of effective process control systems in copper electrowinning tank houses. Keywords: Copper; current efficiency; electrowinning; modelling; plating rate

Jan 1, 2020

By M. R. Khalesi

A method is proposed to estimate the gold content of the ore in the size intervals during size reduction. The method uses the population balance model to trace the gold deportment through the size fractions and monitor the generation of liberated gold grains during the size reduction. The model is calibrated using batch grinding test results of a gold ore. Preliminary results show that the model can be calibrated with a minimum of parameters compared to conventional grinding-liberation models. Keywords: simulation, liberation, gold, exposure, grinding

Jan 1, 2009