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John H. DeYoung

Publications and source records attributed to John H. DeYoung.

5 recordsLinked to original sources

Assessing mineral supply concentration from different perspectives through a case study of zinc

Increasing demand for nonfuel mineral commodities has increased concerns regarding the reliability of their supplies. “Criticality” assessments over the past decade have attempted to capture this concern through a set of indicators, the most common of which quantifies the risk associated with market concentration by applying the Herfindahl-Hirschman Index (HHI) to the world production of a given commodity by country in a given year. Although this approach is useful, it inherently assumes that all of world production is available to the market and is thus potentially at risk. In this analysis, the HHI, as well as HHI weighted by country governance, is calculated for mined and refined zinc using the standard approach of using all world production data and comparing that to the HHI when using the best estimate of what is available to the world market. The results indicate that although the HHI of both mined and refined zinc world production has increased markedly over the past decade, the HHI for what is available to the market for mined and refined zinc has remained relatively constant and low, which is indicative of minimal supply risk. This is mainly owing to the fact that a large and increasing share of the world’s mined and refined zinc production comes from China, but that production supplies domestic consumption as well as small amounts of exports. As a result, the zinc materials that are available to the world market outside of China are produced by a relatively large and diverse set of countries. Although these analyses are specific to zinc, they are likely to be comparable for other commodities of which the largest producers are also the largest consumers and highlight the importance of examining different perspectives in criticality assessments.

Mineral Economics↗

Critical mineral resources of the United States—An introduction

Many changes have taken place in the mineral resource sector since the publication by the U.S. Geological Survey of Professional Paper 820, “United States Mineral Resources,” which is a review of the long-term United States resource position for 65 mineral commodities or commodity groups. For example, since 1973, the United States has continued to become increasingly dependent on imports to meet its demands for an increasing number of mineral commodities. The global demand for mineral commodities is at an alltime high and is expected to continue to increase, and the development of new technologies and products has led to the use of a greater number of mineral commodities in increasing quantities to the point that, today, essentially all naturally occurring elements have several significant industrial uses. Although most mineral commodities are present in sufficient amounts in the earth to provide adequate supplies for many years to come, their availability can be affected by such factors as social constraints, politics, laws, environmental regulations, land-use restrictions, economics, and infrastructure. This volume presents updated reviews of 23 mineral commodities and commodity groups viewed as critical to a broad range of existing and emerging technologies, renewable energy, and national security. The commodities or commodity groups included are antimony, barite, beryllium, cobalt, fluorine, gallium, germanium, graphite, hafnium, indium, lithium, manganese, niobium, platinum-group elements, rare-earth elements, rhenium, selenium, tantalum, tellurium, tin, titanium, vanadium, and zirconium. All these commodities have been listed as critical and (or) strategic in one or more of the recent studies based on assessed likelihood of supply interruption and the possible cost of such a disruption to the assessor. For some of the minerals, current production is limited to only one or a few countries. For many, the United States currently has no mine production or any significant identified resources and is largely dependent on imports to meet its needs. As a result, the emphasis in this volume is on the global distribution and availability of each mineral commodity. The environmental issues related to production of each mineral commodity, including current mitigation and remediation approaches to deal with these challenges, are also addressed. This introductory chapter provides an overview of the mineral resource classifications, terms, and definitions used in this volume. A review of the history of the use and meaning of the term “critical” minerals (or materials) is included as an appendix to the chapter.

Professional Paper↗

Physical factors that could restrict mineral supply

Stages in the metal supply process are affected by each of the following physical (geologic) factors: (1) geographic distribution of concentrations of potential ore minerals, (2) depth of these concentrations, (3) mineralogy, (4) grain size of the minerals, and (5) grade and (6) tonnages of the concentrations. For mineral deposits of each type in each geologic and political environment, the lowest cost metal will tend to be produced first because: (1) the largest deposits tend to be found first, (2) the few largest deposits should reap the benefits of economies of scale and will tend to account for the lion’s share of total metal, (3) higher grade deposits that require substantially less energy per ton of metal than do lower grade deposits will be mined first, and (4) deposits that have the mineralogy and grain sizes that are relatively cheap to process will be produced first. Shallow deposits that are relatively cheap to find and mine and deposits near existing infrastructure will also be produced first. Because stages in the supply process are sequential, problems at any stage caused by the physical factors are reflected in subsequent stages and adversely affect production costs. In the long term, effects of such problems will be not physical shortages of metals but a rapid or persistent increase in real prices of metals.

Economic Geology↗