1. Assessing the Criticality of Metals
Center for Industrial Ecology
Yale School of Forestry & Environmental Studies
Assessing the Criticality of Metals
Thomas E. Graedel
Yale University

2. Metal Life Cycles

3. IMPORT/EXPORT ENVIRONMENT ORE PROCESS - ING FABRICA TION USE WASTE
MGT.
DISCARD
STAF Project
© Yale University 2004

4. Building Multilevel Materials Cycles
European
countries
Planet Earth
Asian
countries
Other
countries
Nine regions
© STAF Project, Yale University
2005

5. Metals Investigated by the STAF Project
Status is as of July, 2006

6. South Africa Chromium Cycle: One Year Stocks and Flows, 2000
Import/Export
Ore, Concentrate 289
FeCr 1129
Semis
Products 4.9
IW 26 HW 3.2
105
Old Scrap 11
FeCr
Production
F&M
Use
Waste
Management
& Recycling
210
Products
Discards
Chem 20 20
4.3
Ref 16
1.9
Stock
Ore 2,156
Metals from Slag
Landfill,
Dissipated
FeCr Slag
Downgraded Scrap 9.6
Prompt
Old Scrap 10
Tailings 15
Ore
Environment
© STAF Project, Yale University, 2007
Gg Cr/yr
FeCr = ferrochromium; IW = industrial waste; HW = hazardous waste; Ref = refractories

7. Japan Chromium Cycle: One Year Stocks and Flows, 2000
Import/Export
Ore, Concentrate 146
FeCr 441
Products 36
IW 71 HW 5.4
Semis
117
Old Scrap 24 24
FeCr
Production
Fabrication
&
Manufacturing
Use
Waste
Management
& Recycling
521
Products
Discards
Chem 15
400 76
324
Ref 11
Stock
Downgraded Scrap 106
Landfill, Waste, Dissipated
FeCr Slag
Prompt 73
Old Scrap 109 67
Ore
Environment
© STAF Project, Yale University, 2007
Gg Cr/yr
FeCr = ferrochromium; IW = industrial waste; HW = hazardous waste; Ref = refractories

8. METAL SPECTRA Understanding how countries use the “suite” of metals
We don’t usually use metals one at a time. How can we explore metals as a group?

9. Database Construction
Choose the metals. We selected seven: zinc, chromium, copper, iron, lead, nickel, and silver
Assemble data in a consistent format across the cycles
Choose a common set of countries. Our set contains data on 49
Normalize the data in some fashion, so that iron flows do not overwhelm other flows. We normalized to per capita global average flows into use
Carry out integrated analyses

10. Constructing the Metal Use Index
f is the metal flow into use, P is population, j is the country index, k the metal index, and g refers to global values

11. Country by Country Metal Use (2000)
© STAF Project,
Yale University, 2010

12. Turkey’s Metal SpectrumFe Cu Zn Cr Pb Ni Ag
log ψj,k
© STAF Project,
Yale University, 2010

13. A Sampling of Metal Spectra
China
Brazil
Chile
Germany
India
Egypt
Yale University, 2010
© STAF Project,
Kenya
Mexico
Japan
New Zealand
Singapore
USA

14. Use Index as a Function of GDP

15. Resource Sustainability and the Issue of Criticality
In 2007, a committee of the U.S. National Academy of Sciences was asked to address the issue of resource sustainability.

16. The Criticality Matrix and the “Region of Danger”
High
Region of
Danger
Impact of Supply Restriction
A product designer or long-term purchaser should try to avoid materials that have both high supply risk and for which the impact of supply restriction would be high. The committee referred to this region as the “region of danger”.
Low
Low High
Supply Risk

17. The Yale Criticality Project Funding: US National Science Foundation and several corporations and organizations
In 2007, a committee of the U.S. National Academy of Sciences was asked to address the issue of resource sustainability.

18. Goals of the Yale Criticality Project
Year 1: Developing a defendable and workable methodology for evaluating the degree to which a metal is “critical”

19. Key Questions to be Answered
What components should be included?
How can the inclusion of these components be justified?
How can these components be evaluated?
How should the component evaluations be aggregated?

20. Supply Risk (Horizontal Axis)
National & Corporate Assessment
Factors
Components
(Mine production-weighted)
Supply Risk
Geological, Technological, Economic Considerations ⅓
DRAFT
Expanded Time to Depletion
100 - τD 1
100 - PPI
Policy Potential Index
Social & Regulatory Considerations ⅓
Human Development Index
100 - EPI
Yale University, 2010
© STAF Project,
Geopolitical Considerations ⅓
Political Instability Index
10 PII
Global Mining Concentration
HHI0.5
Weight
Weight
Trans.

21. Restrictive mining policies decrease availability
Fraser Institute – Policy Potential Index
2008/09 Policy Potential Index
Examines policy-related dimensions that contribute to a jurisdiction's overall attractiveness and its ability to attract exploration investment
Categories include:
Regulations
Taxation
Infrastructure
Labor
Security 20 40 50 30 60 80 90
100 70 10
Transformed Score Scale
McMahon, F., Cervantes, M. “Survey of Mining Companies 2008/2009”. Fraser Institute Annual
Subscript “j” indicates country
Subscript “i” indicates metal
Superscript “Trans.” Indicates the transformed value
PPI indicates the PPI score for country “j”
W indicates % of annual of annual mining production of metal “i” for country “j”
Yale University, 2010
© STAF Project,
Expanded Time to Depletion
Environmental Sustainability Index
Policy Potential Index
Political Instability Index
Global Mining Concentration

22. Vulnerability (Corporate Vertical Axis)
Components
Factors
(per end-use application)
Vulnerability
Importance ⅓
% of Impacted Revenue ⅓
Ability to Pass-through Costs ⅓
DRAFT
Importance to Corporate Strategy ⅓
Substitutability ⅓
Substitute Performance
Substitute Availability
Environmental Impact Ratio
Yale University, 2010
© STAF Project,
Price Ratio
Ability to Innovate ⅓
Ability to Innovate 1
Weight
Weight

23. The Three-Axis Criticality Evaluation ConceptEI
© STAF Project,
Yale University, 2010

24. Goals of the Yale Criticality Project
Year 1: Developing a defendable and workable methodology for evaluating the degree to which a metal is “critical”
Year 2: Using the methodology, evaluate the criticality of a number of different metals

25. Goals of the Yale Criticality Project
Year 1: Developing a defendable and workable methodology for evaluating the degree to which a metal is “critical”
Year 2: Using the methodology, evaluate the criticality of a number of different metals
Year 3: Create a family of scenarios to study the possible evolution of metal criticality

26. Summary
Metal cycles reveal opportunities and challenges invisible to those who know only mining or recycling
If countries use more per person of anything, they do so for everything
A metal’s critical nature is complex and dynamic, but detailed, defendable evaluations should be available in mid to late 2011