natural wealth: an audit
The catalytic converters that keep exhaust pollutants
down to an acceptable level, all use platinum, and it
is slowly lost through exhaust pipes. Platinum is also
a vital component of fuel cells – and supplies
are running out. If all the 500 million vehicles in
use today were re-equipped with fuel cells, losses would
mean that all the world’s
platinum would be exhausted within 15 years.
Unlike oil or diamonds, there is no synthetic alternative:
it is a chemical element, and once we have used it all
there is no way of getting any more. What price then
Alarming? The same goes for many other rare metals
such as indium, which is being consumed in unprecedented
quantities for making LCDs for flatscreen TVs, and the
tantalum needed to make compact electronic devices like
cellphones. How long will global reserves of uranium
last in a new nuclear age? Even reserves of such commonplace
elements as zinc, copper, nickel and the phosphorus
used in fertiliser will run out in the not-too-distant
So just what proportion of these materials have we
used up so far, and how much is there left to go round?
We can't be sure. The annual global consumption of most
precious metals is not known with any certainty. Estimating
the extractable reserves is also difficult. For rare
metals such as indium and gallium, these figures are
kept a closely guarded secret by mining companies.
A materials chemist at the University of Augsburg in
Germany estimates that we have, at best, 10
years before we run out of indium. In January
2003 the metal sold for around $60 per kilogram; by
August 2006 the price had shot up to over $1000 per
Geologists who have calculated the costs of new technologies
in terms of the materials they use, all agree that the
planet's booming population and rising standards of
living are set to put unprecedented demands on the materials
that only Earth itself can provide. Some technologies
are not worth pursuing long term.
Take the metal gallium. This is used with indium
to make a new generation of solar cells that
promise to be up to twice as efficient as conventional
designs. Reserves of both metals are disputed, but in
a recent report by a chemist at Leiden University in
the Netherlands, concludes that current reserves "would
not allow a substantial contribution of these cells"
to the future supply of solar electricity. He estimates
gallium and indium will probably contribute to less
than 1 per cent of all future solar cells - a limitation
imposed by a lack of raw material. How many years would
these minerals last if every human were to consume them
at just half the rate of an average US resident today?
The calculations are crude
but without more recycling, antimony, which
is used to make flame retardant materials, will run
out in 15 years, silver in 10 and indium in under five.
In a more sophisticated analysis Augsberg University
in estimates that zinc could be used up by 2037, both
indium and hafnium - which is increasingly important
in computer chips - could be gone by 2017, and terbium
- used to make the green phosphors in fluorescent light
bulbs - could run out before 2012. It all puts
our present rate of consumption into frightening perspective.
Demand for copper shows no sign of levelling off, and
based on 2006 figures for per capita consumption, by
2100 global demand for copper will outstrip the amount
extractable from the ground.
"We need to minimise waste, find substitutes where
possible, and recycle the rest." University of
Birmingham in the UK, has found that platinum makes
up as much as 1.5 parts per million of roadside dust
and is developing a bacterial process that will efficiently
extract the platinum from the dust.
Tailings from worked-out mines contain small amounts
of minerals that may become economic to extract. Some
metals could be taken from seawater. "It's all
a matter of energy cost. You could go to the moon to
mine precious materials. The question is: could you
"Virgin stocks of several metals appear inadequate
to sustain the modern 'developed world' quality of life
for all of Earth's people under contemporary technology."
And when resources run short, conflict is often
not far behind. It is widely accepted that
one of the key motives for civil war in the Democratic
Republic of the Congo between 1998 and 2002 was the
riches to be had from the country's mineral resources,
including tantalum mines - the biggest in Africa. The
war coincided with a surge in the price of the metal
caused by the increasing popularity of mobile phones
(New Scientist, 7 April 2001, p 46).
The Chinese government is investing in mineral
mines in Africa and buying up high-tech scrap
to extract metals that are key to its developing industries.
The US now imports over 90 per cent of its so-called
"rare earth" metals from China.
Urgent action is required. Firstly, we need accurate
estimates of global reserves and consumption. Then we
need to set up an accelerated programme to recycle,
reuse and, where possible, replace rare elements with
more abundant ones. Without all this, any dream of a
more equitable future for humanity will come to nothing.