Yale researchers have developed a methodology for
governments and corporations to determine the availability of critical metals, according
to a paper in Environmental Science &
Technology.
In "Methodology of Metal Criticality
Determination," the researchers evaluate the importance of scarce metals
using a methodology that determines their supply risk, environmental
implications, and vulnerability to supply restriction.
"In the past few years, a number of organizations have
attempted to evaluate metal criticality, but the methods used have varied
widely and so have the results," said Thomas Graedel, Clifton R. Musser
Professor of Industrial Ecology at Yale. "This is the first time that this
topic has been addressed in the peer-reviewed literature."
The criticality methodology, based on a U.S. National
Research Council template, is designed to help corporations and national
governments evaluate the risk of not having access to critical metals and to
inform strategic decision-making around resource use.
"If you're a corporation, you don't want to design and
manufacture something only to find out that you don't have important
materials," he said.
The criticality methodology evaluates supply risk for
entities that use metals on the basis of three components: geological,
technological, and economic; social and regulatory; and geological. The first
of these components measures the potential availability of a metal's supplies,
and the latter two address the degree to which the availability of the supply
might be constrained.
According to the paper, the most obvious questions related
to a metal's availability in the ground are how much there is, whether it is
technologically feasible to obtain, and whether it is economically practical to
do so.
Regulations and social attitudes can either impede or
expedite the development of mineral resources. For example, communities are
aware of the potential for environmental damage from tailings ponds and may
resist the development of a new mine.
Governmental policies, actions and stability can
significantly affect the ability to obtain mineral resources. Graedel said
that, in general, the more concentrated the mineral deposits in one area, the
higher the risk of supply restriction.
"This work was stimulated by China's
attempt to horde rare earth metals, which are being almost entirely mined and
processed in China,"
said Graedel. "We asked ourselves: How do you know what's scarce? If you
know a metal is scarce, how do you know if you should worry about it? We think
this methodology has substantial legitimacy."
SOURCE –
Yale University
