The concept and measurement of mineral reserves and resources

The distinction between an exploitable and a non-exploitable mineral deposit is dynamic, varying as a function of changing economic and technological factors. A conceptual framework is proposed: ‘reserves’ are restricted to known currently exploitable deposits; ‘known resources’ are reserves plus currently non-exploitable deposits; ‘total resources’ are known resources plus all deposits not yet discovered. The short-term inadequacy of some mineral reserves requites a policy of accelerated mineral exploration and rapid development of new exploration techniques. Future problems could be avoided if the nature of resources is recognized and new mineral extraction and processing techniques for lower grade and unconventional mineral deposits are developed.     

The geographic concentration of world mineral supplies

Mineral reserves are unevenly and erratically distributed throughout the world; those countries which were intensively explored in the past — the USA, Canada, the USSR, Australia, South Africa, and a limited number of Asian, African, and Latin American countries — control a large share of many of the industrially important metallic minerals. Current attitudes towards exploration and the mining industry in both the developed and the less developed countries should clearly encourage rather than discourage new exploration. Given an increase in exploration, new reserves may well be found in previously unexplored areas, but any major increase in world mineral supplies will probably come from mining very low- grade deposits and developing new methods of mining and processing non-conventional ores. While it is vital to increase research and development in exploration techniques and mining and processing technology, it is also critical to maintain current levels of consumption and trade by reversing the trend towards trade restriction on the part of some of the less developed countries who are important mineral exporters.     

Mining and sustainable development: considerations for minerals supply

Sustainable development involves meeting the needs of human societies while maintaining viable biological and physical Earth systems. The needs include minerals: metals, fuels, industrial and construction materials. There will continue to be considerable demand for virgin mineral resources, even if levels of recycling and efficiency of use are optimal, and rates of population growth and globalisation decrease significantly. This article aims to stimulate debate on strategic issues for minerals supply. While the world has considerable stocks of mineral resources overall, international considerations of the environmental and social aspects of sustainable development are beginning to result in limitations on where mining will be conducted and what types of deposits will be mined. Current and emerging trends favour large mines in parts of the world where mining can be conducted within acceptable limits of environmental and social impact. Finding new deposits that meet such criteria will be all the more challenging given a disturbing global decline in the rate of discovery of major economic resources over the last decade, and the decreasing land area available for exploration and mining.
To attract responsible exploration and mining, governments of mining nations will need to provide: regional-scale geo-scientific datasets as required to attract and guide future generations of exploration; resource access through multiple and sequential land use regimes, and frameworks for dealing with indigenous peoples' issues; and arrangements for consideration of mining proposals and regulation of mines that ensure responsible management of environmental and social issues.
The minerals industry will need to continue to pursue advances in technologies for exploration, mining, processing, waste management and rehabilitation, and in public reporting of environmental and social performance.     

The new economic order and world mineral production and trade

World mineral production is dominated by the developed countries — the developing countries dominate production of only tin, cobalt, bauxite, and petroleum. This production pattern is largely the result of historical, political, and economic factors, and is not likely to change radically in the next decade. Apart from petroleum, there seems to be little opportunity for the formation of mineral-producer cartels, although there is considerable scope for constructive producer-consumer agreements. Given the pattern of world mineral production and trade, the developed countries would on the whole benefit more than the developing countries from price increases. The most acute present need is for new means of financing exploration and development of mineral deposits in the developing countries, and for means of redressing the worst imbalances between rich and poor nations outside of the commodity arena.     

US uranium deposits: A geostatistical model

The frequency distributions of both grade and size of metal deposits may be well approximated by lognormal distribution functions. Using data on presently viable deposits and a simplified function which links production cost to deposit grade and size, a bivariate lognormal deposit grade/size distribution may be calibrated for a given geological environment. Exploration is introduced by assuming that the proportion discovered of the potential uranium reserve available at or below a given production cost can be represented by a function of the average deposit size and the unit exploration expenditure. As output the model derives estimates of total reserves linked to maximum production costs and to exploration expenditure where the latter may be expressed either as expenditure per lb of mineral discovered or as a given percentage of operating profit. The model is offered as a basis for discussion, and the conclusions are tentative.     

Metalliferous sediments in the Atlantis II Deep—Assessing the geological and economic resource potential and legal constraints

Projected increases in demand and thus increasing metal prices have brought the exploration and exploitation of marine mineral resources back into focus. The Atlantis II Deep, located in the central Red Sea between Saudi Arabia and Sudan, is one of the largest marine sulfide deposits known, with high concentrations of metals such as zinc, copper, silver and gold. However, little is known about the economic potential of marine minerals as well as the legal constraints. Our geological assessment shows that the deep is similar in grades and scale to large land-based deposits. Its economic potential is far from negligible. The total present value of possible gross revenues for the four metals zinc, copper, silver and gold ranges from 3.03 to 5.29 billion US$, depending on the assumptions made concerning future price development, mass calculation and discount rate. From a legal perspective, a general duty to cooperate in the exploration and exploitation of non-living resources located in disputed maritime areas is identified in both customary international law and in UNCLOS. It is submitted that a joint development agreement is one means of ensuring compliance with this duty in general and in the case of the Atlantis II Deep in particular.     

New mine capacity from yet-to-be found copper deposits

The copper industry in the USA is declining, but exploration for copper has been particularly promising in western Montana. The potential copper mine capacity of the area was estimated by using an interdisciplinary geological-economical assessment technique that categorizes deposits on the basis of development probability. Development probability is quantified and aggregated into potential new mine supply curves, which summarize resource potential of the region. The results suggest that copper resources in Montana and elsewhere are potentially large and that these resources probably will be mined at higher copper prices. This mineral assessment technique increases the usefulness of traditional methods for planners and policy makers.     

United Nations mineral exploration activities in developing countries

The purpose of the United Nations' mineral exploration activities is to assist the developing countries in identifying, evaluating and developing their mineral resources as a means of stimulating their economic development. Since 1978, these programmes have been executed by the Natural Resources and Energy Division of the Department of Technical Co-operation for Development (DTCD) with the United Nations Development Programme (UNDP) providing the bulk of the financing. In the past 30 years, more than 450 projects in some 100 developing countries have been executed at a cost estimated at US$600 million. This input has contributed to the discovery of deposits valued at billions of dollars, many of which are now being mined.     

UN Department of Technical Co-operation for Development regional seminar activities in 1989

The purpose of the United Nations' mineral exploration activities is to assist developing countries in identifying, evaluating and developing their mineral resources as a means of stimulating their economic development. Since 1978, these programmes have been executed by the Natural Resources and Energy Division of the Department of Technical Co-operation for Development (DTCD) with the United Nations Development Programme (UNDP) providing the bulk of the financing. In the past 30 years, more than 450 projects in some 100 developing countries have been executed at a cost estimated at US$600 million. This input has contributed to the discovery of deposits valued at billions of dollars, many of which are now being mined.     

Does taxation alter exploration? : The effect of uncertainty and risk

The effect of resource rent taxation on mineral exploration is a controversial issue on which very little research has been carried out. Simple numerical examples are used in this paper to demonstrate that a ‘pure’ resource rent tax, or Brown Tax, can reduce the extent of exploration of a ‘promising’ deposit by a risk averse explorer, but encourage exploration of ‘unpromising’ deposits. This counter-intuitive result is explained in terms of the effect of the tax and of exploration on the costs of risk and uncertainty.     

Exploration's Role in Iron and Aluminum Supply Since the Second World War

This paper analyses the role of exploration in the worldwide supply of iron and aluminum by (1) reviewing changes in the level and geographic distribution of exploration since 1945, (2) studying important discoveries, and (3) comparing exploration's role in iron and aluminum supply with its role in the supply of other metals. It finds that even though exploration and discovery of new deposits account for part of the tremendous postwar expansion in the level and geographic distribution of iron ore and bauxite production, most of the areas that became major producers were known to contain significant mineralization long before detailed evaluation, development, and mining occurred. These areas needed increased consumer demand, lower ocean freight costs, or improved processing techniques to become economically attractive. Iron and aluminum are easier-to-find yet harder-to-process, and compared with other metals, discovering a better deposit will not reduce overall costs to the same degree as other cost-reducing forms of investment.     

Geological supply and economic demand: The unresolved equation

Whereas the ultimate world supply of minerals is controlled by geological factors, the actual supply at any particular time is controlled by economic factors. Mineral production is a function of investment in exploration, mining, and processing - and research in these fields. Given the long lead time between a decision to explore and actual production from any deposit found, the increasing difficulty of finding deposits in the well prospected parts of the world, the political barriers to exploration in the less developed countries, the energy barriers to mining and processing ever lower grade ores, and the lengthy time required to develop new exploration, extraction, and processing techniques, adjustments in supply in response to changes in demand cannot be assumed to be automatic.     

Risks and opportunities for foreign investment in the mineral sectors of the Central Asian Republics: Kazakstan,Kyrgyzstan, Tajikistan and Uzbekistan

With the dissolution of the former Soviet Union in 1991, the nations of Central Asia gained independence and began the transition to market driven economies. Both the political and economic transformations of the Central Asian Republics (CARs) (Kazakstan, Kyrgyzstan, Tajikistan and Uzbekistan) have been difficult primarily because of a holdover of various centrally planned `command and control' approaches to national development. The extensive mapping and exploration of the CARs during the Soviet era (approximately 1921–1991) led to the discovery of several hundreds of mineral deposits that were subsequently evaluated, and it is this `pool' of known, but undeveloped, deposits which is of major interest to foreign and domestic companies. However, foreign investment in the mineral sectors of the CARs is at best quite modest and there are very few positive signs that foreign investment will increase dramatically in the near term. The major risks that the mining industry faces as it works in the CARs arise primarily from the fact that the nations are transitional economies which lack both a comprehensive legal framework and experience in dealing with foreign mining corporations and their practices. The major risks are political, economic, financial, infrastructure, contractual, environmental, social and cultural and workforce related. If all individual risk factors are weighted equally, the relative ranking of the countries (from least risk to most risk for mineral development) would be Kyrgyzstan, Kazakstan, Uzbekistan and Tajikistan respectively. However, such a classification scheme does not effectively weight the importance of mineral potential. If the risk criteria are weighted with respect to geologic potential, the ranking of the countries would be (from least risk to most risk) Kazakstan, Uzbekistan, Kyrgyzstan and Tajikistan, respectively.     

Exploration and discovery of Australia's copper,nickel, lead and zinc resources 1976–2005

Examination of copper, nickel, lead and zinc (base metals) exploration expenditure and discovery in Australia over the period 1976–2005 reveals some significant trends. Australia's base metal resource inventory grew substantially as a consequence of successful exploration over the period, both through addition of resources at known deposits and new discoveries, notably a small number of very large deposits that underpin the resource base. In 2005, Australia had the world's largest economic demonstrated resources (EDR) of nickel, lead and zinc, and the second largest EDR of copper. Growth in nickel resources has been especially strong owing to discovery of large laterite resources in the late 1990s. Resource life, in average terms based on current EDR and production, is approximately 30 years for lead and zinc, 40 years for nickel sulphide (120 years for all nickel EDR) and 50 years for copper. Despite this success, major increases in production over the period (copper, nickel and zinc output increasing 3–4 fold, lead output doubling) and a fall in discovery rates during much of the 1990s means that resource life for lead and zinc is lower and nickel sulphide comparable now to that in 1976; only the resource life of copper has grown substantially over the period. Current published ore reserves are sufficient for at least 15 years operations at current production levels, but only a small number of the largest deposits currently being mined are likely to still be in production in 20 years. However, several mines have substantial inferred resources that may allow production beyond current mine reserves and there is a substantial number of undeveloped deposits that may provide the foundation for extended or new mining operations. The discovery record is strongly cyclical with resource growth for all the base metals punctuated by the discovery of giant (world-class) deposits each decade: these underpin current and future production. Recent higher metal prices and renewed interest in base metals, especially nickel, has reversed a 10 year decline in base metal exploration attended by reduced rates of discovery and resulted in record expenditure, new nickel, copper and zinc discoveries, and increased resources at a number of existing deposits, notably the Olympic Dam copper–uranium–gold deposit. With the exception of the Prominent Hill copper–gold and West Musgrave nickel–copper deposits, most of the recent discoveries, especially zinc (-lead) deposits, are of small tonnage (some of high grade). Nevertheless, these new discoveries have helped stimulate further exploration and also highlight the potential for further discoveries in little-explored provinces, especially those under regolith and shallow sedimentary cover.     

Natural zeolites

Zeolites, a suite of porous, fine-grained minerals commonly found in certain near-surface, sedimentary rocks, have special physical and chemical properties that could make them valuable to farmers in developing countries. Zeolites have been used to improve soil fertility; develop slow-release fertilizers; improve animal waste disposal; and improve animal health. To date most research on zeolite deposits and their various applications has been undertaken by the industrialized nations. Some zeolite deposits, however, also exist in developing countries and the likelihood of the existence of additional deposits in those countries is high. However, thorough assessment of the mineralogy, geology, and various agricultural uses is still needed. Strengthening developing countries' geological surveys in non-metallic mineral exploration and assessment will improve the likelihood that the use of zeolites will reach their full potential in developing country agriculture.     

油气田绿色矿山建设管理要求与实践

针对目前国家对绿色矿山建设的要求和环境保护面临的新形势,结合国内油气勘探与生产业务绿色发展的相关要求,阐述了油气田绿色矿山建设的发展历程、重点内容、建设标准;总结了绿色矿山建设形成的具体成果和经验,这些经验主要包括注重依法合规、提升绿色理念、科技创新、责任落实、多部门协作等,为下一步建设指导方向,进而提升国内油气勘探与生产业务整体绿色发展水平。     

UNITED NATIONS MINERAL EXPLORATION ACTIVITIES: 1960–1976

The United Nations Development Programme plays an important role in strengthening the economies of developing countries through mineral exploration projects, training in geosciences and institution building. This review demonstrates the effectiveness of such activities, both in terms of the economic value of mineral discoveries, and the less tangible, long-term contribution through development of infrastructure and skills, introduction of modern technology, and building up a body of reliable information as a base for future planning of mineral resources development.     

Using the cumulative availability curve to assess the threat of mineral depletion: The case of lithium

The cumulative availability curve shows the quantities of a mineral commodity that can be recovered under current conditions from existing resources at various prices. The future availability of a mineral commodity depends on the shape of its cumulative availability curve (determined by geologic considerations, such as the nature and incidence of the available mineral deposits), the speed at which society moves up the curve (determined by future demand and the extent to which this demand is satisfied by recycling), and shifts in the curve (determined by cost-reducing technological change and other factors). While the shape of the curve for any given mineral commodity may or may not be known, it is knowable since the geologic processes responsible for the curve's shape took place many years ago. In contrast, the factors governing how fast society moves up the curve and how the curve shifts over time are not only unknown but also unknowable.Using lithium as an example, this article shows that knowledge about the shape of the cumulative availability curve can by itself provide useful insights for some mineral commodities regarding the potential future threat of shortages due to depletion. Despite the inherent uncertainties surrounding the future growth in lithium demand as well as the uncertainties regarding the future cost-reducing effects of new production technologies, the shape of the lithium cumulative availability curve indicates that depletion is not likely to pose a serious problem over the rest of this century and well beyond.     

Mineral sector technologies: policy implications for developing countries

Over the past 20 years the mining industry has been a leader in the conception and application of advanced technologies. New thinking about earth tectonics as well as advances in geophysics, geochemistry, remote sensing, data processing and communications permit more effective and accurate geological exploration. Mechanization, more durable materials and more powerful explosives, as well as computer aided mine design and management have led to substantial gains in productivity. Minerals processing has similarly seen significant technological advances including solvent extraction, electro-winning of metal ores, bath smelting techniques, cyanide leach to produce gold, and bioleaching of sulphide and refractory ores. New technologies have dramatically improved mine health and safety as well as making possible control of water and air pollution. Improved communication and transport have stimulated competition and fostered the internationalization of mineral commodity prices. As these technologies are essentially market driven, developing countries should continue current efforts towards economic liberalization. Promoting investment in mining entails lifting many of the restrictions and taxes that can hinder efficient exploration and development. We examine some developments that have greatly increased the efficiency of exploration, mining and marketing. To obtain maximum benefit from many of these technologies requires governments to adopt a wide range of new policies which are examined in some detail.     

Small–scale mining in South Africa: Past, present and future

Mining is an important part of the South African economy and has been the driver of much of the economic development of the country. However, the small–scale mining subsector still has to realise its full potential. A small–scale mine has been defined as a mining activity employing less than 50 people and with an annual turnover of less than 7.5 million Rand and includes artisanal mines. Small–scale miners are involved in many commodities but there appears to be a bias towards gold, diamonds and quarrying for construction materials, including brickclays. Small–scale mining is regulated by the same legislation (i.e., for the environment, labour, mineral rights, exploration and mining permitting, and skills development) as large–scale mining, though compliance is low, particularly where artisanal mining in concerned. The effective participation of small–scale miners in the mining sector is hampered by their lack of skills, i.e., technical, business and management, and their limited access to mineral deposits, capital and markets. Some of these hindrances have been inherited from the imbalances of the colonial and apartheid eras and continue to act as barriers, making entrance to the industry difficult. For those who have entered the industry out of desperation, as is the case with most artisanal miners, their activities result in negative impacts evident in the inefficient, unsafe and environmentally unfriendly operations. With the advent of the new political dispensation in South Africa, a new era is dawning for the country’s small–scale mining subsector. This has resulted in a change of attitude and new government policies which have led to special programmes being put in place to promote the subsector. Intervention strategies for the support of small–scale mining (some of which are already in operation) include programmes for kickstarting mineral beneficiation and value–addition projects, development of appropriate technologies and skills and technology transfer. Proponents of small–scale mining see a well–regulated industry as being the cornerstone of future rural economic development, particularly for previously disadvantaged communities in the poverty nodes.