Minerals, Critical Minerals, and the U.S. Economy (2008) / Chapter Skim
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4 Applying the Matrix
4 Applying the Matrix
Pages 109-168
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From page 109... ...
Second, the set of minerals had to consist of those that, in the professional judgment of committee members, would likely be included in a more comprehensive assessment of all potentially critical minerals. The next section examines in detail 3 of the 11 selected minerals or families of minerals: copper, platinum group metals (PGMs)
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From page 110... ...
The Vertical Axis: Importance in Use or Impact of Supply Restriction The vertical axis, as noted previously, represents increasing importance in use, or analogously, the increasing impact of a supply restriction for a particular mineral. The methodology uses a relative scale of 1 (low)
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From page 111... ...
Supply Risk FIGURE 4.1 Criticality matrix diagram showing the two main factors that determine the scoring of a mineral's criticality: the impact of supply restriction (importance in use and ability to substitute for the mineral) , and the supply risk (potential factors affecting the availability of the mineral)
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From page 112... ...
for each important application or end use of a specific mineral. The committee asked a number of questions in placing a mineral on the vertical axis.
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From page 113... ...
of supply disruption, which could exhibit itself not only in the form of physical unavailability of a mineral input but even more likely in the form of sharply higher prices for the mineral. As with the vertical axis of the matrix (importance in use)
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From page 114... ...
considered Importance of growth 1 2 3 3 3 in emerging uses that could overwhelm existing global production capacity (1 = low; 4 = high) Relevant for Horizontal Axis Percent U.S.
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From page 115... ...
Applying the Matrix Titanium Mineral Titanium Indium Lithium Manganese Tantalum Concentrates Metal Vanadium 107 Not 314 164 Not 3255 68 estimated estimated ~10 0 90 90 10 (for 90 11 (partly pigments) galliumdependent)
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From page 116... ...
The term does not signify that extraction facilities are in place and operative." obtain supply preferentially, even while other, less powerful end users are unable to buy a mineral at all or must pay a sharply higher price. As with the vertical axis, the actual placement of a mineral on the horizontal axis represents the judgment of the committee, rather than the result of a quantitative analytical method.
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From page 117... ...
, marginally economic (marginal reserves) , and some of those are currently subeconomic (subeconomic resources)
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From page 118... ...
The world reserve base-to-production ratio is also expressed in years and integrates aspects of geologic, technical, and economic availability, but with less restrictive economic constraints. The ratio represents that part of an identified resource that meets certain physical and chemical criteria but includes resources that are currently economic (reserves)
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From page 119... ...
The most-critical minerals are both essential in use (difficult to substitute for) and prone to supply restrictions.
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From page 120... ...
= 3.84. TABLE 4.2 Scoring the Vertical Axis of the Criticality Matrix for Example Mineral X Application Group Proportion of Total U.S.
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From page 121... ...
fig 4-2 This is essentially a weighted score between 1 and 4 for mineral X for all applications on the vertical axis of the matrix. As demonstrated below, the relative impact of a restriction in supply of a particular mineral has several dependencies.
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From page 122... ...
The scoring for the vertical axis considers not just impacts on products with a restriction, but also the ease of substitution for a mineral (in the event of a supply restriction) in a technical sense and the broader market consequences of a supply disruption.
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From page 123... ...
production currently is only about 2 million pounds. Globally, the consumption of uranium is 170 million pounds, but 2005 production was only 108 million pounds, the balance deriving from a diminishing secondary supply of deactivated nuclear weapons.
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From page 124... ...
All production processes were successfully tested, but none was commercialized. Copper Vertical Ranking -- Ease of Substitution and Impact of Supply Restriction on User Sectors Copper was one of the first metals ever used by humans and continues to be extensively employed today.
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From page 125... ...
TABLE 4.3 Relative Importance of End Use Applications for Copper Proportion of Impact of Supply Weighted Application Group Total U.S. Market Restriction Score Building and construction 0.55 3 1.65 Energy provisioning 0.15 4 0.60 Transportation 0.15 2 0.30 Machinery and equipment 0.10 2 0.20 Telecommunications 0.05 1 0.05 Overall importance in use 2.80 NOTE: Proportion of total end use for each application was determined from Joseph, 1999.
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From page 126... ...
On the whole, building sector use of copper is increasing moderately, and for this reason, the committee evaluates the importance of an impact in supply restriction for this end use to be somewhat high (3) (see Table 4.3)
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From page 127... ...
Horizontal Ranking -- Risk to Copper Supply or Copper Availability • Geologic availability. As discussed in Chapter 3, copper mining is concentrated in Chile, with Australia, Indonesia, Peru, and the United States also having significant operations. Many other countries mine copper at somewhat lower levels.
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From page 128... ...
Combined with its weighted composite score of 2.8 on the vertical axis, Figure 4.3 shows that although copper is important to many aspects of daily activities and technologies, its availability does not make it a critical mineral at this time. Rare Earths Vertical Ranking -- Ease of Substitution and Impact of Supply Restriction on User Sectors The REs are subdivided into "light" and "heavier" elements reflecting their atomic numbers.
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From page 129... ...
Supply Risk FIGURE 4.3 Criticality assessments for end use applications of copper and the composite criticality score for copper (black hexagon)
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From page 130... ...
The diversity of end uses is primarily a reflection of the fact that the RE family includes many elements, some with only a few important applications. For the purposes of simplifying the evaluation of the impact of supply restriction of REs, the seven end uses for REs are here grouped into four categories having somewhat similar applications (Table 4.5)
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From page 131... ...
, and praseodymium (Pr) , when alloyed with non-RE metals, can be used to make very-high p erformance permanent magnets for miniaturized electronic and electrical devices with applications in automobiles, audio and video equipment, and military devices.
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From page 132... ...
. Given the increasing importance attached by our society to clean and healthful air, improved medical diagnostic tools, and electronic data transfer and communication, we suggest that the highest level of impact of supply restriction or importance in use (4)
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From page 133... ...
The Mountain Pass mine was last in operation in 2002 and has since been on a "care-and maintenance" basis. • Technical availability. The crustal concentrations of the REs are relatively high, rendering the term "rare earth" a practical misno mer; even the two least abundant, thulium and lutetium, are nearly 200 times as abundant as gold.
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From page 134... ...
Even if RE produc tion at the Mountain Pass property resumes and continues, the product spectrum is narrow, chiefly comprising yttrium, cerium, europium oxide, a lanthanum-rich mixture of RE metals including praseodymium and neodymium, and a mixture of mainly samarium and gadolinium. The Mountain Pass carbonatite deposit is very depleted in RE elements heavier than dysprosium, compared with some Chinese deposits.
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From page 135... ...
• Economic availability. While the world reserve-to-annual produc tion ratio is high at 715 (Table 4.1) , it is deceptive because China accounted in 2006 for 97.6 percent of global mine production and the Chinese ratio of reserves to production is significantly lower, although still ample, at 225.
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From page 136... ...
Impact of Supply Restriction 3 2 Emission controls, magnets, electronics Metallurgical, optical, ceramics Petroleum refining 1 (low) Other applications (unspecified)
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From page 137... ...
In the automotive sector, catalyst composition depends on price, supply, fuel, and other factors. Palladium may be partially substituted for platinum in catalytic converters for gasoline vehicles.
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From page 138... ...
a Weighted Score Relative Cost Application Group Platinum Palladium Rhodium of Disruption Platinum Palladium Rhodium Autocatalysts for motor vehicle emission 0.50 0.50 0.84 4 2.0 2.0 3.36 control Industrial and other applications 0.25 0.05 0.16 4 1.0 0.20 0.64 Fuel cells for transportation or -- -- -- 2 -- -- -- stationary applications Jewelry, dental, and electronics 0.25 0.45 -- 1 0.25 0.45 -- applications Overall score 3.25 2.65 4.00 a Johnson Matthey, 2007.
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From page 139... ...
Because of the lack of data on these emerging applications, the committee was not comfortable in ranking the immediate impact of a supply restriction for these end uses higher than 2, but the committee acknowledges that demand could very well increase in the future. The committee also notes that supply restrictions could postpone the development and implementation of technologies that could reduce fossil fuel consumption, increase energy efficiency, reduce greenhouse gas emissions, and improve air quality.
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From page 140... ...
A low value (1) or low impact of supply restriction for PGMs is suggested for this application category.
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From page 141... ...
The recycling technology for PGMs is among the most advanced of the metals, especially as far as industrial catalysts are concerned. Overall, there are no immediate concerns for PGM availability from a technical perspective (1)
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From page 142... ...
show that, together, South Africa and the Russian Federation ac counted for well over 80 percent of the 2006 global supply of platinum, palladium, and rhodium. Both countries have proven to be reliable suppliers.
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From page 143... ...
of palladium is somewhat more diversified, North American production would likely be inadequate to supply critical needs in case the supply of palladium from the Russian Federation or South Africa was interrupted. Furthermore, the only current U.S.
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From page 144... ...
. • Economic availability. About 10 mining companies and a smaller number of smelting and refining companies account for substan tially all primary PGM production.
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From page 145... ...
The underlying database may provide insight into the economic outlook for existing mines, but the ratios provide no insight into market dynamics. As Table 4.1 shows, platinum is produced primarily by primary platinum mines with by-products that may include other PGMs, nickel, c opper, and cobalt.
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From page 146... ...
. The development of an infrastructure to collect and recover PGMs in North America has led to the development of a new economic activity that reduces import dependence and the associated risks.
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From page 147... ...
, and the relatively high probability of a PGM supply restriction, PGMs are considered to be critical minerals (Figure 4.5)
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From page 148... ...
In less complete fashion than has been done above, the committee presents a discussion of the criticality aspects of eight of these minerals. Gallium Vertical Ranking -- Ease of Substitution and Impact of Supply Restriction on User Sectors Gallium is a soft, silvery metal with many unusual properties.
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From page 149... ...
The composite criticality for gallium is located together with the other seven "criticality candidates" on Figure 4.6.
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From page 150... ...
End use applications, their weighted scores, and the composite score for indium are presented in Table 4.9. Horizontal Ranking -- Risk to Indium Supply Some indium is found in pure form, and it occurs in only a few minerals, such as indite.
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From page 151... ...
The risk of supply restriction through export quotas from one or another supplier to the 151
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From page 152... ...
, based on supply sources, substitutability, and recycling constraints. The composite criticality for indium is located together with the other seven criticality candidates on Figure 4.6.
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From page 153... ...
End use applications, their weighted scores, and the composite score for lithium are presented in Table 4.10. At present we conclude that the current importance of lithium would be low, but believe that this element must be followed closely as this situation could change in the future.
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From page 154... ...
The composite criticality for lithium is located together with the other seven criticality candidates on Figure 4.6. Manganese Vertical Ranking -- Ease of Substitution and Impact of Supply Restriction on User Sectors Manganese is a silver-white metal that can be hardened by alloying with carbon.
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From page 155... ...
The composite criticality for manganese is located together with the other seven "criticality candidates" on Figure 4.6.
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From page 156... ...
mine production has been reported since 1959 (South Dakota) and the likelihood of discovering domestic ore reserves is negligible.
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From page 157... ...
Tantalum Vertical Ranking -- Ease of Substitution and Impact of Supply Restriction on User Sectors Tantalum is a metallic element having high ductility, is a good conductor of electricity, and is highly resistant to corrosion by acids. Its major use is in the production of electronic components, mainly capacitors.
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From page 158... ...
Marketa Restriction Score Capacitors 0.65 3 1.95 Specialty alloys, other 0.35 2 0.70 Overall importance in use 2.65 a USGS, 2007.
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From page 159... ...
economy. Conversely, supply restrictions would be much easier for the dominant pigments sector to address.
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From page 160... ...
, based on supply sources, substitutability, and recycling constraints. The composite criticality for titanium is located together with the other seven criticality candidates on Figure 4.6.
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From page 161... ...
These considerations lead the committee to conclude that the impacts of supply disruption and weighted rankings are as shown in Table 4.16, where the alloys have been combined into a single end use category. Horizontal Ranking -- Risk to Vanadium Supply Vanadium is found in a broad spectrum of minerals distributed in many countries, as well as in Canadian tar sands and crude oil produced by Mexico and Venezuela.
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From page 162... ...
U ranium can also be recovered as a by-product of phosphoric acid production, and there are two plants each in Florida and Louisiana on standby status. The United States at present is essentially 100 percent dependent on imported vanadium feedstocks, with 74 percent of ferrovanadium from the Czech Republic and 82 percent of vanadium pentoxide from South Africa.
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From page 163... ...
The committee considers supply risk for vanadium to be only moderate (2) for all applications, and the composite criticality for vanadium is located together with the other seven criticality candidates on Figure 4.6.
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From page 164... ...
Minerals that rank high on both axes of the criticality matrix are characterized as "critical minerals," although it is important to understand that a mineral can rank high on one or both axes for quite different reasons. Examples discussed earlier in this chapter include the following: • PGMs, several different applications of which are regarded as hav ing high importance in use; • REs, whose criticality is strongly dependent on supply risk concerns; • Titanium, for which a minor use in terms of mass is vital to U.S.
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From page 165... ...
Impact of Supply Restriction 3 Copper Gallium Indium Lithium Manganese 2 Niobium Platinum Group Metals Palladium Platinum Rhodium Rare Earth Elements 1 (low) Tantalum Titanium Vanadium 1 (low)
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From page 166... ...
• In placing a mineral or mineral product on the vertical axis (im pact of supply restriction) , technological importance in use is easier to evaluate than the other, largely economic factors.
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From page 167... ...
, 2006. Regional review: South Africa.
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