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Exploration requires a lot of skill, technical knowhow, and money; the money is usually less painfully available when provided by a profitable cash flow of an existing organisation that has income against which exploration cost is deductible. Planning the financing for development of a proven resource should begin at the earliest stages even while the mining plan is being formed up. The character of the participants has a bearing on the nature of the financing "package" and the structure that is to be selected for the venture. The security for borrowers in a remote mining resource is no better than the capacity of the participants to bring that resource to profitability in line with the findings of a thorough feasibility study. Taxation considerations related to the structure selected and the timing of the cash flow are of vital importance. Sales contracts have generally been a basic requirement of institutions financing mineral mining projects. Clauses relating to price, price escalation, and currency var- iations, are key factors in those contracts. Initial contracts have generally been required to cover initial overall costs.

Jan 1, 1974

By Ryan CG, Ramsden AR, Sie SH, French DH, Griffin WL

Proton microprobe and electron microprobe analysis are being used in combination for in situ determination of the trace element contents of oxide, sulphide and silicate minerals in a sample of the Merensky Reef. Initial results indicate that chromites contain only Ni, Zn, Ga, Zr ar d Nb. Platinum-group elements, if present, are at concentrations less than 2 to 6ppm. Ru, Rh and Pd are the only platinum group elements to be consistently detected in the sulphides. PentLindite is the most important host for these elements with the concentration of these elements being dependant upon the mineral association in which it occurs

Jan 1, 1989

Access to land for exploration, development and mining purposes is extremely critical to the viability of the mining industry and subsequently the well being of society.The mining industry has been subject to environmental controls and considerations for the past 20 years. Today there is greater land use competition and more debate as to its use. To retain reasonable access the mining industry must comply with the rules and regulations by which it is governed.A new set of rules and regulations have been approved for use in Queensland, known as the Mineral Resources Act 1989. This Act clearly outlines the titles available and the requirements to obtain access.There are three main titles of interest to mining companies. These are an Exploration Permit, Mineral Development Licence and a Mining Lease.The Exploration Permit (EP) is for exploration purposes. Applications for EP's are assessed on their content and past performances. An EP is granted subject to a security deposit and conditions. Prior to entry the EP holder is required to inform the land owner of the proposed activities and times of entry.

Jan 1, 1990

By Clark T. M

Underground coal mining involves the disturbance of natural strata stresses formerly in equilibrium, the production of noxious and flammable gases and dust which can be both an explosion and a health hazard. It involves also the use of heavy, large equipment operating on natural floors and in confined spaces. Such operations are required to be carried out under artificial light. Much of the easier won coal, that is the shallower coal, from this State has already been extracted and in future workings will be required to go deeper. As the depth increases strata pressures will increase, gas production is likely to be greater and the production of dust will also increase. A further problem which has not yet reached significant proportions in Australia is the potential rise in working temperature. This will be occasioned not only by the use of large items of equipment which themselves generate heat, but due also to thermal gradients as the depths increase. The need for better employee training is now being widely recognised throughout the industry. Under present highly mechanised conditions new employees should not be required to work with or near heavy mobile machinery without proper training

Jan 1, 1976

SASOL Synthetic Fuels has recently completed the design of sampling systems for raw and blended coal feeding the gasifiers at Secunda, South Africa. The new systems will replace manual, stopped belt sampling and have been designed to achieve specific accuracy targets on a daily basis. The sampling system is unusual in the coal industry in that the fines content (-5.5 mm nominal) of the coal is very critical and is to be determined with high accuracy.The sampling system was designed to meet carefully considered target accuracies using methods of modern sampling theory. The heterogeneity of the coal streams involved with respect to the critical analytes was determined by appropriate sampling and sample analysis. The statistical characterisation of the time variation of analytes in the process streams was based on variograms derived from on-line ash gauges. From this point, the design was completed using fundamental statistical sampling theory and some simulation studies. The paper discusses the development of the sampling system design in detail as well as the plans to use the data stream to provide timely alarms when the coal quality deviates from the target specification.

Jan 1, 2002

By Wang Xia, Zhou Aiming, Shi Shengyi

Zhangmatun Iron Mine is situated in the suburbs of Jinan city, Shandong, China. Because of surface environmental constraints, no suitable site can be selected to dispose of mill waste. The full mill tailings must be disposed of underground. This paper deals with the work conducted at Zhangmatun mine to develop a total tailings backfill system, taking advantage of a doubleshaft blade mixer and an activating agitator to prepare backfill. Cement and ground slag are added to tailings for strength development. Two stopes have been filled and the pillars have been effectively mined out during the field trial. The application of innovative total tailings backfill technology is a new concept at the mine. Detailed planning has achieved a close integration of mining, milling and backfilling. Full mill tailings, with or without rock, are disposed of underground in a continuous process to fill, totally and systematically, the cavities formed by mining. Utilisation of cemented tailings backfill solves not only the problem of disposal of mill waste, but also the resource problem of providing backfill materials to the mine. The strategy also maximises ore recovery for the mine.

Jan 1, 1998

By Somasundaran P

Controlled modification of mineral/liquid interfacial properties by adsorption is critical for mineral processing operations such as flotation, filtration, dispersion and flocculation. Ionic/nonionic surfactant mixtures usually show enhanced surface activity and salt tolerance over ionic surfactants, and this is especially beneficial for flotation of salt type minerals in which case dissolved multivalent cations in high concentrations usually cause loss of anionic surfactants by precipitation. Adsorption of nonionic/anionic surfactant mixtures on kaolinite has been studied with sodium dodecylsulfate as the anionic surfactant and octaethyleneglycol mono-n-dodecylether as the nonionic surfactant. Synergistic interaction between these surfactants was found to cause adsorption of the nonionic surfactant with its hydrophilic chains protruding into the bulk, leading to substantial changes in flotability and dispersion characteristics of kaolinite. Similarly, hydrophobicity changes are observed also' for silica particles upon adsorption of nonionic ethoxylated alcohols owing to possible changes in the orientation of the adsorbed surfactant species at the interface. Also, based on the results obtained with surfactant adsorption, a hydrophobically modified polymer was used successfully to disperse graphite particles in aqueous solution.

Jan 1, 1993

By S H. Marshall, H Hutcheson

Conventional batch cell and FASTFLOT pilot plant studies of reverse flotation of coarse marcasite and pyrite (100 - 400 μm) to reduce the sulphidic sulphur content of a rutile concentrate, were undertaken. The batch cell experiments found no significant improvement in sulphur removal with acid wash and copper activation of marcasite and pyrite. Batch cell trials also identified potential difficulties of conventional mechanical cell plants operated at 40 per cent w/w solids. The FASTFLOT 250 B-2 pilot plant trials indicated that with a 0.6 - 0.7 per cent w/w feed sulphur content, target product grade can be met on a routine basis by a three-stage FASTFLOT plant floating coarse marcasite and pyrite. The trials found that 150 g/t PAX dosage and 15 minutes conditioning time are adequate reagentisation for 40 per cent w/w solids feed to the FASTFLOT plant.

Jan 1, 1998

Optimising a mining or a quarrying operation about the overall cost is quite a challenge as there never is a situation where we have exactly the same conditions regarding rock properties, explosives' performance, mining equipment or evironmental restrictions. The amount of endless influencing parameters and variables make the evaluation process difficult. The enormous progress we have seen during the recent two decades in computing has however significantly increased our ability to evaluate and process the information gathered, and refine our existing prediction models. Refined models demand an increasing volume of good quality information to show reliable conformity with reality. There is a great need for co-operative work in the mining and quarrying society if we shall be able to screen all available data, systematically find the key-parameters influencing the results and to build robust scientific models. No organisations today have all the skilled people needed or can afford to hire the necessary specialists in all the overlapping branches. This paper highlights some on-going work where the Dyno Explosives Group is adding some new pieces to the giant jigsaw puzzle representing the ultimate model of the mining and quarrying operations we all of this society would like to see completed.

Jan 1, 1995

By C Deacon

It is common practice to include microspheres or similar density reducing agents in inherently insensitive water-based commercial explosives to achieve detonative sensitivity in the absence of chemical sensitisation. It has recently become possible to similarly include microspheres in LDAN (low density ammonium nitrate). Further to previous studies and publications to determine the benefits resulting from the use of microsphere enhanced LDAN technology in blasting, additional advantages are described in this document. These include range tests at independent testing facilities (Universal Tech Corporation û USA) which reflect results observed in the field, and support theoretical assumptions made when the products were introduced. Additionally, on-site studies in opencast pits using Heavy-ANFO blends incorporating modified LDAN, show that monetary savings can be realised through significant advantages gained in plant throughput and explosives use.

Jan 1, 1999

The efficiency with which it is expected that a particular coal may be burnt in a power station boiler significantly affects the value of the coal. Consequently many laboratory tests have been developed to provide data on the combustibility of coal. Computer modelling of coal combustion has also provided insight into limits on coal burn- out. Such modelling suggests that burnout of bituminous coal in a power station boiler will be strongly influenced by physical limits on the diffusion of oxygen to the individual coal particles. Coal chemical reactivity appears to be relatively less important. As a consequence of the diffusional limits, significant improvement in burnout is achieved either by producing less large p.f. particles or by providing sufficient furnace residence time to burn the large particles. Field data from a variety of power stations supports these cn.clusions. Burnout was also found to correlate well with volatile content for a number of coals from widely different sources. This is expected as the high vola- tile coals produce less residual char to be burned by the relatively slow heterogeneous Combustion.

Jan 1, 1987

FINANCE FOR EXPLORATION Two factors have basic importance in relation to the availability of finance: the apparent success of continuing exploration activity and tax concessions. It is not proposed to discuss the effect of existing tax incentives, as these have already been outlined and are generally accepted as being reasonably attractive; certainly not a deterrent to possible investors. However, it is obvious that the greater the tax incentives, the greater the amount of money that will be attracted, and the wider the number of people who can be brought into the pool. If, as is suggested, the chance of discovery is related to expenditure and effort, then the more money attracted, the better the prospects of significant finds. It is probably correct to assume that the largest expenditure in mining will come from, or be induced by, people expert in the field, people who are fully aware of the risks and benefits and perhaps making conservative decisions because of this awareness. Insofar as the general public is concerned, while in the first burst of enthusiasm it will frequently follow any promoter, in the long run it too will become more sophisticated and will strongly support only those promoters and companies of good repute and proven record.

Jan 1, 1971

Financial theory often takes some time to penetrate industry and when it does it can result in a paradigm shift in valuations and mental models. The Black Scholes option valuation was first published in 1973, although the authors were only awarded a Nobel Prize in 1997. The valuation of real options has been applied to the oil and gas industry for some time, however it has only recently been more widely applied to the non-oil, mineral resource sector. The use of real option valuation (ROV) for the valuation of marginal and short mine life resource projects is a more useful valuation tool than the conventional DCF, NPV valuation tool. The application of ROV has major implications for corporate strategy. It generally favours equity over debt funding and non-hedging over hedging. A retrospective assessment of the successful development of the Lennard Shelf Operations demonstrates the concepts of implementing real options and the value destruction of limiting operational flexibility through debt and hedging activities.

Jan 1, 2003

By C A. Fleming, C J. Ferron, P T. OÆ

A new process is described which allows for direct recovery of base and precious metals (Au and PGMÆs) from sulphide concentrates or other feedstocks. The process was developed initially for application to ores or concentrates that are too low-grade for economic treatment by the conventional smelting and matte leaching process (for PGMÆs). It is now believed that the process may be widely applicable to a variety of materials including PGM concentrates containing high amounts of chromium or magnesium. Operating conditions have been identified under which gold, the PGMÆs and the base metals dissolve simultaneously in a pressure leaching autoclave. The product of this leaching process can then be treated by one of several flowsheets, of which the preferred will likely involve solid/liquid separation, followed by precipitation (or adsorption on activated carbon) of gold and the PGMÆs, followed by copper solvent extraction/electrowinning. Depending on the concentrations of nickel and cobalt, the copper raffinate would either be partially recycled to the autoclave to allow Ni/Co concentrations to build up, or it would proceed directly to a Ni/Co refinery. This paper deals with the pressure leaching process and the recovery of gold and the PGMÆs from the pressure leach product.

Jan 1, 2000

By B Hu, B Zhang, J Wang, H Ma, D Liu, L Han

Zeolites are potential carriers of slow release fertilisers due to their unique phenomenon for salt occlusion. A comparative study was performed on the capacities of potassium nitrate (KNO3) occlusion in molten KNO3 treated synthetic 4A and 13X zeolite molecular sieves with main channel sizes of 0.41 x 0.41 nm and 0.74 x 0.74 nm respectively. The results show that in a laboratory setting, the treated zeolite 4A contained 13.57 per cent of occluded KNO3 and the treated zeolite 13X did not contain any. This was confirmed by the regular release of K+ and NO3- during washing both treated mixed samples with water and by their IR spectra and TG analysis. There are also changes of the relative intensities of peaks in X-ray diffractograms of both treated zeolite samples. K+ release from molten-KNO3 treated zeolites in deionised water and simulated soil solution shows that release of K+ from KNO3 occluded in zeolite 4A are slow and steady. Proper size fit between the channel size of zeolites pore and the size of K+-NO3- ion pair of KNO3 is the decisive factor for zeolites to occlude KNO3.

Jan 1, 2008

By S Slusarczyk, Z Kozlowski

Vibration of surface caused by seismic quakes can make a risk to great mining costruction. We have to do with this risk in the Belchatow open cut mine where seismic quakes of various energy and range have occured since the end of 1970s. The seismic risk influence on the mine structure with the special attention to the slopes of an internal dump has been presented. Hydrogeological and geotechnical conditions of the lignite mining and internal dumping of overburden and ash from Belchatow power plant have been considered. Seismic activity in Belchatow open cut from 1979 to 2001 was described and the connection between mine working and seismicity of this area was investigated. The energy and approximate location of the quakes and seismological parameters of the strongest ones observed from 1995 to 2001 were presented. The mechanism of the quake focuses was determined by means of the primary-arriving wave method. Stability of the slopes was evaluated by means of the Fellenius method. It has been found that seismic events occured in Belchatow region may cause only local eboulements whereas there are not any safety risks to the stability of slopes of the internal dump in Belchatow open cut.

Jan 1, 2003

Research and Technical Services, Department of Mines Western Australia The nine papers received for this technical session cover a very wide range of hydrological problems in various parts of the world. Three of these papers deal with hydrological predictions for new mines, while three are concerned with the prediction of water chemistry. The three remaining papers deal with gas injection as a dewatering tool, discharge formulae verification and the use of a physical model to predict subsurface strata movement and fracture development due to longwall mining. Hydrological problems in mine planning represent a major risk in many mining operations, booth as a potential life or equipment hazard and a major financial risk. The initial paper selected to review was therefore one by the president of a gold mining company, rather than by one of the specialist scientists, to remind us all that the main reason problems are faced and overcome in the mining industry is usually a commercial one. In one commercial undertaking, the ability to accurately assess future risk is a highly desirable planning tool and hence in mining, the ability to predict the nature and magnitude of hydrological problems is n i-an varxi imnnrfant

Jan 1, 1988

By S Ramsay, D Povey

This paper presents recent case study data collected by field portable x-ray fluorescence spectrum analysers (FPXRF) as part of grade control activities at three separate (nickel, copper and copper/gold) mining operations. FPXRF has been under utilised for grade control in recent years, largely because the success of early versions of FPXRF was limited to a few metals (eg tin). Efforts to utilise these early versions for other metals was largely unsuccessful and created a perception that FPXRF could not be utilised more broadly within the mining sector and specifically the area of grade control. The structural setting of the analytical function within mining operations has also contributed to the under utilisation of more recent FPXRF instrumentation. The concept of FPXRF as a grade control tool straddles the boundaries of the geology and laboratory departments. As such, this option is often not considered as part of an assessment of grade control procedures for new and existing mining operations. This paper assesses data collected by Australian and New Caledonian miners using FPXRF technology as part of the grade control function and concludes that FPXRF can provide operational and cost benefits to certain mining operations.

Jan 1, 2003

Computers are playing an increasing role in the management of technical data in mines. Companies are re-assessing the role of their data processing departments as users demand computer resources in non-accounting areas. Data of all kinds is now being seen as a, company resource, and the role of computing professionals is to help to manage the data flow, not merely to manage computers. The concept of distributed data bases puts the responsibility for data entry, editing and updating with the user. This challenges conservative views of centralized control of computing, suggesting, instead, centralized co-ordination. A survey of the possible applications of computers in technical areas points up the special requirements of handling raw, processed and consolidated technical data. Technical data bases have become flexible as mini- computer hardware and software have rapidly developed. Management has the ultimate responsibility for efficiently administering corporate data bases, and it must ensure suitable policies are developed for this purpose, with enough flexibility to cope with the impact of fast changing technology.

Jan 1, 1980

Drilling is one of the most, significant cost components of any stoping or develop- ment operation. Two of the factors contri- buting to the drilling cost are the supply and servicing of consumable items such as drill rods and bits. The purchase cost of consumable items can be controlled to a large extent by using the correct balance of quality and price. However, the service cost is a less easily controlled factor and it is in this area where potential savings are significant. In June, 1976 a six month trial period was commenced at The Zinc Corporation, Limited and at New Broken Hill Consolidated Limited with two separate suppliers supplying and ser- vicing all longhole drilling parties (one supplier for each mine) at a guaranteed cost per metre. As a result of this six month trial period a new contract was commenced in December, 1976 with one supplier supplying and servicing all longhole drilling parties at both ZC and NBHC for a twelve month period. This concept has now been in operation for over twelve months and has proved to be a significant means of slowing down the increas- ing cost associated with drilling operations.

Jan 1, 1977