Keynote Address
Global Nonfuel Mineral Resources and Sustainability
By Friedrich-Wilhelm Wellmer1
and Jens Dieter Becker-Platen1
materials for construction and many of the industrial minerals).
In Germany, for example, nonmetallic mineral resources
total about 80 percent of mineral commodities consumed. The
lifetime curve of nonmetallic resource production in a country
shows a positive time offset relative to the curve for production
of metallic resources and attains a maximum when almost all of
the metal mines in that country have been abandoned (fig. 1). It
follows that the industrial countries, which are the major importers
of mineral resources and thus are customers of the rest of the
world, must have a vested interest in the sustainable development
of mineral resources, not only from a global point of view
but also in a local context (Wellmer and Becker-Platen, 2001).
Sustainable Development
The Concept of Sustainable Development
Sustainable development is a normative term like liberty
or equality according to German philosopher Immanuel Kant.
In the United Nations (U.N.) Report, “Our Common Future,”
commonly called the “Brundtland Report,” sustainable development
is defined as development that meets the needs of the
present without compromising the ability of future generations
to meet their own needs (Brundtland, 1987, p. 8). This
has become the most accepted definition internationally. It has
been expanded by the U.N. Environment Programme, which
added that the concept also requires the maintenance, rational
use, and enhancement of the natural resources base that
underpins ecological resilience and economic growth and that
it implies progress toward international equity (United Nations
Environment Programme, 1989).
The next steps were the Rio Declaration at the U.N. Conference
on Environment and Development in Rio de Janeiro in
1992 and Agenda 21, which stress three objectives of sustainable
development—(1) to conserve the basic needs of life, (2)
to enable all people to achieve economic prosperity, and (3) to
strive toward social justice. All three objectives initially should
be considered to have the same priority. Whereas the Brundtland
definition deals with “intergeneration fairness,” Agenda
21 adds the element of “intrageneration fairness.”
Introduction
All countries are responsible for safeguarding the
environment and for maintaining a relatively intact world for
future generations. This is true not only for the mining and
mineral exporting countries but also for the industrialized ones
that buy and import most of their raw materials, especially the
high-value metals and energy supplies. Together, all countries
are responsible for working out a global strategy for exploiting
mineral resources that fulfills the requirements of sustainable
development.
Highly industrialized countries such as those of Western
Europe, which import all of their metallic mineral resources
and most of their energy supplies, still produce a large proportion
of their required nonmetallic mineral resources (that is, raw
1
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR) [Federal Institute
for Geosciences and Natural Resources] and the Lower Saxony Geological
Survey (NLfB), Stilleweg 2, D–30655, Hannover, Germany.
Figure 1.  Comparison of the production trends of metallic ores,
industrial minerals, and aggregates in industrialized countries
(Wellmer and Lorenz, 1999; modified from Bristow, 1987).
Productionvalue
Early
industrial
development
Peak
position of
mining
industry
Highly industrialized
phase with peak position
of secondary industry
TimeNonmetallic minerals (industrial
minerals, aggregates)
Aggregates alone
Metals
   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
Guidelines for Sustainable Development
The first practical guidelines for sustainable development
came from the German forestry administration. The man credited
with inventing sustainable development is von Carlowitz,
who published the book “Sylvicultura oeconomica” (von Carlowitz,
1713). He was the head of the mining administration
of the famous silver mining district around Freiberg, Saxony.
In this position, he was responsible not only for the mining
and smelting operations in his district but also for the forestry
because wood was needed for timbers in the underground
mines and vast amounts of wood were needed to produce the
charcoal required to smelt the silver ores. He realized that the
uncontrolled cutting of the forest for these purposes would
lead to the collapse of forestry production. He was the first to
spell out what sustainable development meant in forestry (that
is, that the amount of wood cut should not exceed the growth
rate).
Although his rule for renewable resources is quite logical,
at the beginning of the 18th century, it was difficult for it to
become broadly accepted. Even today, there is international
resistance to similar sustainable development initiatives; for
example, the use of quotas on fish catches to avoid overfishing.
The reason for such resistance was and always is that,
when sustainable development is introduced for a natural
resource, structural changes must occur in the economy and in
society. People and interest groups directly affected frequently
resist these changes.
In contrast to guidelines for the use of renewable
resources, guidelines for nonrenewable resources are more
difficult to develop. In 1993, the Enquete Commission on
Protection of Man and the Environment, set up by the German
Federal Parliament, formulated four general rules for the sustainable
development of natural resources (Enquete-Kommission
Schutz des Menschen und der Umwelt, 1993); these rules
can be applied worldwide. Rules 1 and 2 concern resources,
and rules 3 and 4 concern the resilience of the environment.
Rule 1. Use of renewable resources.—The rate of consumption
of renewable resources should not exceed the
rate at which they can be regenerated. This rule is the
same in essence as that already formulated by von Carlowitz
(1713).
Rule 2. Use of nonrenewable resources.—The consumption
of nonrenewable resources should not exceed the
amount that can be substituted by functionally equivalent
renewable resources or by attaining a higher efficiency in
the use of renewable or nonrenewable resources.
Rule 3. Material and energy input.—Material and energy
input into the environment should not exceed the capacity
of the environment to absorb them with minimal detrimental
effects.
Rule 4. Rate of anthropogenic input and environmental
interference.—The rate of anthropogenic input and environmental
interference should be measured against the
•
•
•
•
time required for natural processes to react to and cope
with the environmental damage.
If one critically examines the various elements of the concept
of sustainable development as described above, together with
these four rules for the sustainable development of natural
resources, there is an apparent contradiction.
The creation of wealth to achieve economic prosperity, as
outlined above, is one of the three cornerstones of sustainable
development in the Rio Declaration of 1992. However, there is
no creation of wealth without the direct or indirect use of nonrenewable
resources. Even today, mineral resources are needed
in our highly industrialized society, wherein creation of wealth
is based to an ever-increasing degree on information technology.
For example, 31 metals are needed to construct a personal
computer (PC) (Jeffery, 1998). A PC requires electricity to
function. Electricity is generated and delivered as a part of the
vast infrastructure required to build and maintain modern societies.
An infrastructure in turn requires construction materials
such as steel and bricks, energy for heating and transport, and
food produced in abundance by using mineral fertilizers.
Later, we will examine in detail how rule 2 can be
fulfilled for nonrenewable resources. We interpret rule 2 as
follows: “The consumption of nonrenewable resources should
not exceed the amount that can be substituted by functionally
equivalent resources or replaced in other ways” (Wellmer and
Becker-Platen, 2002).
Let us consider why we need natural resources. With a
few notable exceptions, exemplified here by potassium and
phosphate used as fertilizers in agriculture, it is not the metal
or raw material as such that is important, but a function that
can be fulfilled by the material properties of the commodity
(for example, the electrical conductivity of copper). Other
commodities, sometimes using a totally different technology,
also can perform these functions. For example, copper telephone
wires are used for transmitting information. These have
been extensively replaced by fiberglass cable made of silica,
whose availability on Earth is limitless. Another solution to
the problem of transmitting information is wireless transmission
using directional radio antennae or satellites. Each solution
requires different materials.
Mineral Resources as Renewable
Resources
Metallic and nonmetallic resources normally are considered
to be nonrenewable. However, in a few exceptional cases,
they can be viewed as renewable. An example is diatomite.
One of the uses of diatomite is as a filter medium for beverages,
and one of the places this mineral is exploited is in Lake
Myvatn, Iceland. Diatoms in the lake metabolize siliceous
exhalations percolating through the lake and regenerate the
deposit as they die and settle to the lake bottom. Another
example is gravel in rivers that are eroding mountains. If
gravel can be extracted from a riverbed without increasing the
erosive power of the river, and thus damaging embankments
or bridges, its extraction meets the sustainable development
guideline of rule 1 for renewable resources. In this way, about
5 million metric tons of gravel are produced annually from
rivers flowing from the Alps into Germany. Nevertheless,
demand for gravel in southern Germany is substantially higher.
Substances dissolved in seawater also can be considered
renewable resources. The prices of sodium, potassium,
bromine, and magnesium salts, for example, will determine
when technologies will be developed for commercial extraction
of these salts from the ocean. Already, about 16 percent of
sodium chloride is produced directly from seawater (Wellmer
and Becker-Platen, 2001).
Mineral Resources as Nonrenewable
Resources
Most of the mineral resources we consume, of course, are
nonrenewable. Nonetheless, ways must be found to fulfill the
Brundtland Report requirement that future generations be able
“to meet their own needs.” Current annual world consumption
of mineral and energy resources is about 32×109
metric tons
(32 billion metric tons), worth about952 billion euros. Figure
2 is a bar diagram showing the annual world production of all
mineral and energy resources by quantity in 1998. Figure 3 is
the equivalent diagram based on value. In both diagrams, the
base of the pyramid is formed by sand and gravel, aggregates,
and energy resources, all of which are required to meet our
basic needs for housing, heating, and transportation. Most of
the nonmetallic resources are in the lower half of the quantity
pyramid, whereas most of the metals are in the upper part
of the quantity pyramid. Only the following nine metals are
produced at a rate of more than 1 million metric tons annually:
iron (Fe), by far the largest, aluminum (Al), copper (Cu), manganese
(Mn), zinc (Zn), chromium (Cr), lead (Pb), titanium
(Ti), and nickel (Ni).
The very top of the quantity pyramid, of course, is made
up of the precious metals and semiprecious and precious
stones that together are represented by the most important
precious stone, diamond. The special and “electronic” metals,
like gallium, indium, or germanium, also are at the top of the
quantity pyramid (fig. 4). These metals are the most important
commodities in our information technology society. They are
essential for electronic components in measuring and control-engineering
technology, which are key technologies for
increasing the efficiency with which we utilize our resources,
especially our energy resources. These metals are used annually
in tens or hundreds of metric tons and are critical components
for the efficient utilization of resources that are used and
consumed on the order of millions and billions of metric tons.
One can ask whether we can maintain this level of consumption
and still fulfill the requirements of sustainable development,
particularly in view of the fact that we have consumed
more resources since World War II than during the whole of
our long history before that. Figure 5 shows the relative cumulative
consumption trends of the “old” metals—gold (Au), tin
(Sn), copper (Cu), and iron (Fe)—using total consumption
as of today as 100 percent. Of these four metals, iron is the
“youngest.” The beginning of its use in the Middle East marks
the birth of the Iron Age about 3,400 years ago; gold, tin, and
copper have been used even longer. Figure 5 clearly shows
that in 1945, at the end of World War II, cumulative consumption
of these metals was less than 50 percent of the cumulative
consumption of 1995, only 50 years later.
Few people realize how much the production and consumption
of natural resources have accelerated. The following
two examples are given to illustrate this trend.
The most intensively researched historical statistics probably
are those for gold production (table 1). During the
nearly 1,000 years from the end of the Roman Empire
at about A.D. 500 to the discovery of the Americas by
Columbus in 1492, the estimated total world gold production
was about 2,500 metric tons, approximately the same
as a single year’s production today.
The famous Rammelsberg mine in the Paleozoic Harz
Mountains in Germany is a polymetallic sedimentaryexhalative-type
deposit that was in production for more
than 1,000 years, from 968 to 1988. For long periods
of time in the Middle Ages, the mine produced 10,000
metric tons per annum (t/a). It rarely produced more than
30,000 t/a, which was equivalent to only 6 weeks’ production
at the end of its lifetime. The deposit contained 32
million metric tons of ore. By using a formula for the
optimal lifetime of a deposit today (Taylor, 1978), we can
calculate that the deposit would be exhausted in only 15
years.
It is tempting to correlate the increase in mineral resource
production and consumption with the increase in world population,
which grew from about 1.6 billion people in 1900 to the
following milestones: about 2.4 billion in 1950, about 3.2 billion
in 1965, and more than 6 billion (6×109
) in October 1999.
However, the bulk of mineral resource consumption takes
place in industrialized countries, which have had only a very
moderate population increase. The large increase in population
has occurred mainly in the developing nations (fig. 6). This
uneven consumption pattern, however, offers an opportunity to
find a solution to the problem of sustaining the future supply
of mineral resources.
The efficiency of production and utilization of mineral
raw materials will have to be increased. This improvement
requires investments in research and development, which
can be much more easily undertaken in the relatively rich
industrialized nations than in the relatively poor developing
nations. Moreover, industrialized nations start much higher on
the learning curve for efficient use of natural resources than
do the developing nations. After development by industrial
nations, more efficient technologies then can be adopted by
1.
2.
Global Nonfuel Mineral Resources and Sustainablity   
   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
QUANTITY
Industrial minerals
Precious metals and
gemstones
Fuels
Metals (nonprecious)
Kyanite and Related Materials
Graphite
Electronic Metals
Columbium
Aluminum
Titanium
Bentonite
Manganese
Talc and Pyrophyllite
Diatomite
Lead
Feldspar
Asbestos
Peat
Gypsum, Anhydrite
Chromium
Magnesium
Uranium
Magnesite
Vanadium
Tin
Molybdenum
Cobalt
Boron
Silver
Fluorspar
Sulfur
Nickel
Zinc
Rock Salt
Phosphate
Potash
Platinum-Group Metals
Kaolin
Diamonds
Industrial Sand
Clay
Copper
Iron
Gold
Aggregates
Lignite
Sand and Gravel
Coal
Natural Gas
Petroleum
Mica
3.2
16
24
26
32
35
45
206
118
135
209
431
401
0.02
0.35
2.5
456
648
773
2,060
7,470
7,870
8,790
8,800
20,100
12,200
9,610
25,300
26,900
27,400
36,600
44,800
55,600
103,700
191,100
300,000
500,000
562,000
848,000
2,357,000
3,578,000
3,735,000
4,100,000
>15,000,000
1,970
1,100
3,040
2,770
4,810
5,890
4,180
Barite
Zirconium
Antimony
Tungsten
Figure 2.  World primary production of mineral and energy resources in 1998 by quantity (Kippenberger, 2001). Ores are given as metal
equivalent in thousands of metric tons; natural gas, in millions of cubic meters. The label “Diamonds” represents all precious and
semiprecious gemstones. Electronic metals include gallium, indium, and germanium. Details about the top of the pyramid are in figure 4.
Figure 3.  World primary production of mineral and energy resources in 1998 by value (Kippenberger, 2001). Values are given in millions
of euros. Commodities are the same as in figure 2.
Kyanite and Related Materials
Industrial minerals
VALUE
Precious metals and
gemstones
Fuels
Metals (nonprecious)
Graphite
Electronic Metals
Columbium
Aluminum
Titanium
Bentonite
Manganese
Talc and Pyrophyllite
Diatomite
Lead
Fluorspar
Asbestos
Peat
Gypsum, Anhydrite
Chromium
Magnesium
Uranium
Magnesite
Vanadium
Tin
Molybdenum
Cobalt
Boron
Silver
Feldspar
Sulfur
Nickel
Zinc
Rock Salt
Phosphate
Potash
Platinum-Group Metals
Kaolin
Diamonds
Industrial Sand
Clay
Copper
Iron
Gold
Aggregates
Lignite
Sand and Gravel
Coal
Natural Gas
Petroleum
Mica
64
69
120
130
146
158
194
200
237
336
345
388
391
439
440
556
576
618
659
689
727
821
862
864
882
918
926
1,550
1,590
1,610
1,820
1,890
2,930
3,030
3,140
3,510
3,760
3,950
3,960
4,910
9,500
9,800
15,200
20,900
23,100
30,300
97,000
122,000
161,000
412,000
1,040
Barite
Zirconium
Antimony
Tungsten
Global Nonfuel Mineral Resources and Sustainablity   
   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
Platinum-Group Metals (302 t)
Beryllium (286 t)
Indium (230 t)
Gallium (60 t)
Germanium (56 t)
Rhenium (37 t)
Diamonds (30 t)
Scandium (100 kg)
Tantalum (412 t)
Selenium (2,071 t)
Gold (2,479 t)
Figure 4.  A modified expansion of the top of the quantity
pyramid from figure 2, showing the precious metals, precious and
semiprecious stones (designated by “Diamonds”), and electronic
metals (including gallium, indium, and germanium) (Kippenberger,
2001). Quantities are in metric tons (t) and kilograms (kg).
Cumulativehistoricamounts
producedupto1945
50%
Au
Sn
Fe ore
Cu
CUMULATIVEPRODUCTION,INPERCENT
100
80
60
40
20
1800 1820 1840 1860 1880 1900 1920 1940 1960 1980 1990 2000
YEAR
Figure 5.  Cumulative world production of iron (Fe) ore, gold
(Au), copper (Cu), and tin (Sn) (Wellmer and Becker-Platen, 2001;
courtesy of Encyclopedia of Life Support Systems Publishers,
Oxford, United Kingdom).
Population
DEVELOPED
REGIONS
UNDERDEVELOPED
REGIONS
1950
1990
1950
1990
1950
1990
1950
1990
1950
1990
1950
1990
1950
1990
Al
2/19
Cu
4/19
Zn
3/25
Pb
5/18
Ni
1/13
Steel
5/25
%
%
80
68 77
32 23 98 81 96 81 97 75 95 99 87 95 7582
80
100
60
60
40
40
20
20
0
Figure 6.  Distribution in percent of world population and metal
consumption between the underdeveloped and developed regions
in 1950 and 1990. Data for developed regions from Wellmer and
Becker-Platen, 2001; courtesy of Encyclopedia of Life Support
Systems Publishers, Oxford, United Kingdom. Al, aluminum; Cu,
copper; Zn, zinc; Pb, lead; Ni, nickel.
Table 1.  World gold production.
[From Wellmer and Becker-Platen, 2001; courtesy of Encyclopedia of Life
Support Systems Publishers, Oxford, United Kingdom]
Period
Production,
in metric
tons
3900 B.C. – A.D. 500 (end of Roman Empire),
4,400 years
10,257
500 ����������������������������������������–���������������������������������������1492 (discovery of America), 992 years 2,472
1493 �����������������–����������������1999, 507 years 125,059
Total: 5,899 years 137,778
1999, 1 year 2,514
the developing nations to meet the natural resources needs of
their growing populations. Such development and application
of technology allow us to extend the three-cornerstone concept
in the Rio Declaration of 1992 to a four-cornerstone concept
by adding the need for research and technology to achieve a
higher efficiency in the use of natural resources (fig. 7). In the
long run, including research and technology is the only possibility
for achieving sustainable development globally.
The Future Availability of Resources
Lifetime of Reserves
The future availability of resources commonly is estimated
by using the concept of “reserves lifetime,” which is defined as
the known reserves divided by current annual consumption. In
practice, however, reserves lifetime is a completely inappropriate
measure of future availability. This estimate is influenced by
many factors, such as type of deposit, distribution of reserves
according to deposit size, costs, price level, intensity of exploration,
and development of technology. The reserves lifetime is
nothing more than a statistical snapshot of a dynamic system that
says much more about the need for innovation than about true
future availability. Commodities that occur in extensive seams,
such as potash or coal, and that cover considerable areas in some
deposits typically have lifetimes of more than 150 years because
it is much easier to calculate and extrapolate reserves for such
commodities than for those occurring in more local discontinuous
concentrations. Typical representatives of the commodities
having localized concentrations are lead and zinc, which have
lifetimes of only 20 to 25 years. The lifetimes for lead and zinc,
however, have remained the same since 1950, despite an increase
in production from 1.7 million metric tons of lead and 2.2 million
metric tons of zinc in 1950 to 3.0 million metric tons of lead and
8.0 million metric tons of zinc in 1999. The stability of these
lifetimes means that a dynamic balance between consumption
and the discovery of new reserves of these two metals has been
maintained for the last 50 years. Obviously, a far larger and more
constant effort is needed to keep a dynamic balance for commodities
with short lifetimes than for those with very long lifetimes
(Wellmer and Becker-Platen, 2001). Thus, reserves lifetime
figures can be interpreted as indicators of the need for innovation
and of the available time buffer during which functionally equivalent
substitutes for scarce resources must be found in accordance
with rule 2 of the Enquete Commission.
With this understanding of the reserves lifetime concept,
let us take a look at mineral fertilizers. Generally, we need only
the functions of natural resources, not the natural resources as
such. Among the exceptions to this statement are potassium
(potash) and phosphorus (phosphate). Both are essential plant
nutrients. Like water, they have no substitutes. In this respect,
potassium and phosphorus must be considered among the most
critical commodities. Fortunately, their reserves lifetimes are
quite high—81 years for phosphorus and 329 years for potassium—giving
humanity a substantial time buffer to find sustainable
solutions. Moreover, the ultimate source of potassium is
seawater, which is practically a renewable resource. Although
it is more difficult to develop a comparable concept for sustainability
of phosphorus, future options to do so are likely to
include improved fertilizing technology, precision farming, and
improved recycling of wastes such as manure.
Supply and Demand Cycle of Mineral
Resources
If one wants to understand the future supply of mineral
resources, one must consider their supply and demand cycle.
This cycle is driven primarily by the price of the commodity,
although it should be noted that other aspects, such as
increased environmental awareness and concern, are playing
an increasingly important role. It also is essential to consider
these cycles in connection with one further resource—human
creativity. Discovery of new reserves may be viewed as only a
temporary possible solution to mineral resource sustainability.
Under rule 2 of the Enquete Commission, a number of other
potential solutions to sustainability of nonrenewable resources
are emphasized and rely on human creativity. Examples for
mineral resources include (1) enhancing recovery from the
mineral deposit, (2) finding new substitutes, (3) improving
recycling, (4) reducing consumption by more efficient utilization,
and (5) finding totally new solutions (such as the new
technologies that allow transmitting information over fiberglass
cables instead of copper wire or by wireless transmission
Figure 7.  The three-cornerstone concept of the 1992 Rio Declaration (economy, ecology, and social justice) extended to a fourcornerstone
concept that includes research and technology to achieve sustainable development globally.
ECONOMY
to enable all people to achieve
economic prosperity
SOCIAL JUSTICE
to strive toward
social justice
ECOLOGY
to conserve the basic
needs of life
RESEARCH AND TECHNOLOGY
to achieve the three-cornerstone concept
of the Rio Declaration 1992
The three-cornerstone
concept of the
Rio Declaration 1992
Amendment
Global Nonfuel Mineral Resources and Sustainablity  
   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
using satellites). Some of these examples are described in
more detail below.
Enhancing recovery.—In a worldwide materials-flow
study, Kippenberger (2001) examined the recovery rates for
mining, beneficiating, and smelting eight mineral and energy
commodities: iron, aluminum, copper, nickel, chromium,
manganese, phosphate, and coal. His results (summarized in
table 2) show that total recoveries of these commodities from
mining to smelting are well below 100 percent, indicating that
significant improvements in utilization efficiency are possible
in the future.
Finding new substitutes.—The effect of rising prices as
a driving force on finding new solutions to mineral resource
sustainability is well demonstrated by the cobalt supply shortage
resulting from the political Shaba crisis in Zaire in 1978. This
crisis caused the price of cobalt to skyrocket. Zaire, now the
Democratic Republic of Congo, is the world’s largest cobalt
producer. In 1976, the German Government commissioned
a study to analyze what effect a shortfall of 30 percent of a
commodity would have on industry. For chromium and cobalt,
which were considered very difficult to replace with substitutes,
it was found that about 6 million jobs would be affected. However,
this study totally underestimated the flexibility of industry
to react to drastic price rises. Shortly after the price rise, new
substitutes (ferrites) were invented, replacing cobalt in permanent
magnets and thereby totally changing the consumption
pattern for cobalt (Wellmer and Becker-Platen, 2001).
Improving recycling.—What is the aim of recycling? Is it
to make maximum use of the secondary material per se, or is
it to minimize environmental impact (for example, by reducing
energy input and thus CO2
emissions)? Most people would
agree that it should be the latter. Consequently, the optimum
solution may not be to recycle 100 percent of the secondary
raw material (Wellmer and Becker-Platen, 2001). Take aluminum
as an example. The results of an investigation by Alkan
and others (1999) to find the optimum rate for recycling aluminum
used in packaging are shown in figure 8. The optimum
in this case is 90 percent, definitely not 100 percent.
A potential material for metal recycling can be classified
according to whether the metal it contains is concentrated or is
dilute and highly disseminated. Recycling of relatively concentrated
secondary metals requires less energy than does the smelting
of their primary ores or concentrates. Recycled aluminum, for
example, requires only 5 percent of the energy needed to produce
primary aluminum; for copper, the figure is 20 percent; for lead,
50 percent. Lead in car batteries is an example of a concentrated
metal that is easily recyclable. The high concentration of lead in
these batteries, combined with their relatively short lifetime, is the
Figure 8.  Primary energy requirement for producing aluminum as
a function of the recycling rate for aluminum in packaging material
(modified from Alkan and others, 1999; courtesy of Encyclopedia of
Life Support Systems Publishers, Oxford, United Kingdom).
Point based on results
of model calculations
and industrial data
PRIMARYENERGYREQUIREMENT,IN
GIGAJOULESPERMETRICTONOFALUMINUM
ALUMINUM RECYCLING RATE, IN PERCENT
300
200
100
0 20 40 60 80 100
Table 2.  Recovery rates during mining, beneficiation, smelting, and refining of aluminum,
chromium, iron, copper, manganese, nickel, phosphate, and hard coal.
[Modified from Kippenberger, 2001]
Commodity
Percent of world production
included in this survey
Total recovery,
in percent
Share of underground
mines, in percent
Aluminum Mines 79 87 0
Smelters/refineries 96
Chromium Mines 77 65 70
Smelters/refineries ~100
Iron Mines 65 77 4
Smelters/refineries 90
Copper Mines
(Relative to capacity)
~75 71 35
(estimated)
Smelters/refineries ~94
Manganese Mines 51 47 30
Smelters/refineries ~97
Nickel Mines 70 76 53
Smelters/refineries 70
Phosphate Mines 61 64 3
Hard coal Mines 91 77 75
reason why lead in car batteries has a recycling rate of more than
50 percent. In contrast, zinc in skin cream and titanium in paint
are at the other end of the concentration scale. No one would ever
think of trying to recover metals from these products. The more
disseminated a metal is in the secondary raw material, the more
energy required to purify it.
Applying a Natural Resources Hierarchy to
Sustainable Development
Substitution of one raw material for another, such as plastics
or concrete for metals, occurs constantly in industry and is
driven by economics. However, substitution also can be driven
by efforts to promote sustainable development. One way to do
this is through consideration of a hierarchy of relative mineral
resource values like that illustrated in figure 9. The top of the
hierarchy is occupied by the most valuable resources (that is, the
energy resources represented in fig. 9 by fossil fuels). The next
lower value category consists of those mineral resources whose
deposits are created by natural enrichment (for example, metalliferous
deposits and some nonmetallic deposits like phosphate
and barite). The next lower level consists of bulk raw materials
such as those used in construction and those whose availability
from the geological point of view is unlimited in the Earth’s crust.
Also included are materials such as magnesium and potassium,
which are present in practically unlimited quantities in the oceans
and may be considered essentially as renewable resources. At the
base of the hierarchy are the waste products and residues from
beneficiation or burning of higher value resources. An example is
ash from coal-fired powerplants, which can be used for making
cement, thereby replacing primary cement raw materials. Lower
value resources should always substitute for higher value ones.
Whenever possible, the aim of mineral policy in the
sense of sustainable development must be to utilize low-value
resources at the base of the mineral resources hierarchy in order
to conserve high-value resources at the top. An example of how
this may be achieved is through a materials-flow law like Germany’s
Waste Avoidance, Recovery and Disposal Act, which
penalizes waste disposal. This law promotes maximum utilization
of waste products and minimum disposal of waste. Other
measures include regional planning that permits unimpeded
access to bulk mineral resources, in combination with laws
encouraging environmentally compatible mineral extraction.
The application of the mineral resources hierarchy to sustainable
development is illustrated by the following two examples.
Triple-pane window glass is mandatory in Sweden.
When the resulting energy savings for heating a house
exceeds the amount of energy required to manufacture the
triple-pane glass for the windows, then the energy balance
is positive. Thus, raw materials that are lower in the
resources hierarchy (sand, limestone, dolomite, and soda
ash) replace energy resources at the top (fig. 9).
A new high-speed railway system under construction
in Europe is required to follow the most direct routes
possible between cities. Consequently, many tunnels and
bridges are being built. Tunnels make up 34 percent and
bridges make up 12 percent of the northern half of the
new railway line between Hannover in northern Germany
and Munich in southern Germany (Geissler and others,
1982). Primarily, the new railway system improves
traveltime, but it also represents a massive investment in
bulk construction materials and steel to improve energy
efficiency.
Indicators of efficiency in the utilization of natural
resources have been developed in various countries because,
as the consideration of the mineral resources hierarchy above
illustrates, it is not helpful to consider natural resources as
equivalent entities (for example, making 1 metric ton of an
energy resource equivalent to 1 metric ton of a metal or 1 metric
ton of a bulk material). Rather, it is more helpful to measure
the efficiency of utilization of the resources at the top of the
hierarchy by measuring the intensity of their use. For the energy
resources, the intensity of use is measured by the ratio of a
unit of energy consumed to a unit of gross national product, or
vice versa. Figure 10 shows how energy efficiency in Germany
improved from 1990 to 1996 in the context of the nation’s goal
to double energy production by 2020 (Bundesministerium für
Umwelt, Naturschutz und Reaktorsicherheit, 1998).
The Importance of Learning
Learning is a process that normally follows a sigmoidal
curve. At the beginning, the learning curve is almost flat; that
is, the start is difficult; then the curve steepens, and finally
1.
2.
Figure 9.  Hierarchy of mineral resources for managing
sustainable development (Wellmer and Becker-Platen, 1999;
courtesy of Encyclopedia of Life Support Systems Publishers,
Oxford, United Kingdom). Resource values increase upward.
Fossil fuels
Mineral deposits formed by
enrichment processes (for
example, metalliferous deposits)
Bulk raw materials
Waste products and residues as
potential raw materials
Substitution
Substitution
Substitution
Substitution
Processingwastesandresidues
Global Nonfuel Mineral Resources and Sustainablity  
10   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
600 MW
“Refitting”
of existing
powerplants
600 MW after
“refitting”
800 MW
Schwarze Pumpe
950 MW
Niederaußem
930 MW
Lippendorf
950 MW powerplant with
optimized technology
50
45
40
35
1974 1976 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010
EFFICIENCY,INPERCENT
YEAR
Figure 11.  Increase in the efficiency of generating electricity in German lignite-fired powerplants; information from DEBRIV (Deutscher
Braunkohlen-Industrie-Verein e.V.; German Association for the Lignite Industry). MW, megawatt.
Figure 10.  Development of energy efficiency in Germany (modified from Bundesministerium für Umwelt,
Naturschutz und Reaktorsicherheit, 1998). Measured in millions of Deutsche Marks (DM) gross national product
per petajoule (PJ) consumed.
1990
100
200
300
400
0
1993 1996 2000
YEAR
2005 2010 2015 2020
ENERGYEFFICIENCY,INMILLIONSOF
DEUTSCHEMARKSPERPETAJOULECONSUMED
188
208
377
Aim (1990–2020): To double energy productivity
it flattens again when a saturation stage is reached and the
rate of learning declines. All of the examples cited above of
methods for replacing nonrenewable resources by functionally
equivalent resources or achieving higher efficiencies in using
mineral resources as required by rule 2 of the Enquete Commission
can be shown to follow such a learning curve. On the
other hand, experience shows that learning curves may start
anew with a technological breakthrough or radical innovation.
This circumstance is exemplified by a learning curve based on
the efficiency of generating electricity with lignite as fuel in
German powerplants (fig. 11).
Learning is critical for improving the efficiency of
production and utilization of our natural resources. In figure
6, it was shown that the bulk of natural resource consumption
is occurring in the industrialized nations. This group of
countries has gone through a learning curve, becoming more
and more efficient in using natural resources. This occurrence
is illustrated for copper consumption in figure 12. The growth
rate shown in figure 12B generally decreased from the end of
World War I to the middle of the 1980s. Since that time, the
growth rate for copper consumption has flattened out in the
industrialized nations. However, the growth rates in world
consumption are increasing again because of high growth
rates in takeoff and developing nations like China (Wellmer
and Wagner, 2000). The consequence is that we shall see the
development of a new learning curve in the countries with
high growth rates today.
It has been argued that takeoff and developing nations
take over more efficient technologies immediately and skip
less efficient intermediate steps. This certainly is true for
selected technologies; for national economies as a whole,
however, this development has not been observed so far (for
example, steel consumption, as shown in fig. 13).
Figure 13A shows the intensity-of-use (IOU) factors
for steel for a selected group of developing, takeoff (newly
industrialized), and industrialized nations. A bell-shaped curve
can be clearly seen in the plot of kilograms of iron consumption
per $1,000 gross national product versus gross national
product per capita. The intensity-of-use factors rise within
the group of developing nations, reach a peak in the group of
takeoff nations, and decline toward the group of industrialized
nations. This curve results mainly because of the in­creasing
importance of the tertiary service sector but also because of
learning effects. If the theory that takeoff and developing
nations skip stages in favor of more efficient natural resource
utilization were true for entire national economies, a flattening
of this bell-shaped curve as shown in figure 13B would be
expected. What we observe, however, is the opposite trend.
Figure 13C shows the intensity-of-use factors for two time
slices—1985 and 1995. It can be clearly seen that the bellshaped
curve has a more pronounced peak in 1995 than in
1985. This difference obviously means that the growth of the
developing nations and takeoff nations is based on more rather
than fewer natural resources.
The three-cornerstone concept for sustainable development
in the 1992 Rio Declaration was extended herein to a
four-cornerstone concept by adding research and technology
(fig. 7) to improve efficiency in the use of natural resources.
Figure 13 illustrates overall the need for increased efforts in
this field in order to reverse the trend shown in figure 13C.
To increase the efficiency of entire national economies
with respect to the utilization of natural resources, one must
take into account that each economic system has to advance
through its own stages of learning. In the metallurgical field,
industrialized nations have advanced to a relatively efficient
stage that optimizes energy input (Wellmer and Becker-Platen,
2001). The present situation in industrialized countries, however,
is the result of many learning steps, which proceeded
through stages that were inefficient and certainly not sustainable
by today’s standards. A good example is the use of charcoal
for smelting, which led to excessive cutting of timber and
the formulation of the first rule for sustainable development by
von Carlowitz (1713).
Developing nations, of course, will not go through these
same stages again but, for a variety of reasons, will have to
start on a lower part of the learning curve before reaching
a high degree of resource efficiency. As an example, many
smelters produce not only metals but also residues like slag
and sulfuric acid. In industrialized nations today, all residues
can be used in most cases in other industrial sectors (for example,
slag in the construction industry; sulfuric acid in many
chemical processes). The result is that residues at the base
of the natural resources hierarchy of figure 9 are used again,
thereby replacing primary higher value resources. However,
such reuse of residues requires a developed chemical industry,
which a developing nation generally does not have when it
starts to industrialize by using its own natural resources.
The Sink Problem of Natural Resources
and the Resilience of the Environment
So far we have dealt only with rules 1 and 2 of the
Enquete Commission. We also have to consider rules 3 and 4,
which address the resilience of the environment.
Per the maxim, “He who mines must dig,” digging is
unavoidable, even though it has an environmental impact. In a
recent study by Neumann-Mahlkau (1997), it was shown that
anthropogenic mass movements have reached the same order
of magnitude as geogenic mass movements: about 35 billion
cubic meters per annum (m3
/a) compared to about 37 billion
m3
/a. Fortunately, humanity has learned much over the past 30
years about reducing the environmental effects of mining. Good
mining practices always use the best available technology that
also takes into account inescapable economic considerations.
Such practices sometimes are labeled “BATNEEC”; that is, best
available technology not entailing excessive costs. Implementing
BATNEEC means increasing limits on the quantity of water
and reagents reaching the environment from the beneficiation of
ores and implementing strict regulations about restoring mine
sites. It also involves minimizing the land area used for mining.
For example, it has been calculated that only about 0.01 percent
per year of the land area of Germany is used for exploiting
natural resources (Gwosdz and Lorenz, 2000). Moreover, this
percentage must have a bias toward higher land usage than in
other equivalent industrialized countries because Germany is
the world’s largest lignite producer, having very large open pits.
Germany also is a significant peat producer, for which relatively
large production areas are required, as well. Nonetheless, all
land used for mining and quarrying today is used only intermittently
in most industrialized nations; such land areas are “borrowed.”
In Germany, for example, all such land must be restored
for industrial, agricultural, forestry, or recreational purposes or
as a nature reserve (re­naturation).
Accidents, especially those involving tailings dam failures,
have caused considerable damage to the environment
and, in the past, led to widespread public criticism of the mining
industry. Although environmental damage should not be
Global Nonfuel Mineral Resources and Sustainablity   11
12   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
Figure 12.  Worldwide copper consumption and growth rates from 1900 to 1998 (Wellmer and Wagner, 2000). A, Annual
worldwide copper consumption. B, Growth rates of worldwide copper consumption where 5-year mean values are
calculated relative to the previous 5-year period.
12
8
4
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 1998
YEAR
METALCONTENT,INMILLIONSOFMETRICTONS
Trendline
Annual consumption
1900 1910 1920 1930 1940 1950 1960 1970 19901980 1998
20%
10%
15%
5%
0%
-5%
-10%
GROWTHRATE
YEAR
A
B
GNPPERCAPITA,INTHOUSANDSOFU.S.DOLLARS
Fe CONSUMPTION, IN KILOGRAMS PER US$1,000 OF GNP
4020 60 10080 120
10
15
5
0
0
20
25
35
30
Philippines
Peru
Morocco
Turkey
Jordan
Newly industrialized
countries
Developing
countries
Industrialized
countries
Taiwan
Malaysia
Korea
Singapore
Japan
USA
Germany
Norway
Fe consumption in 1985
Malaysia
GNPPERCAPITA,INTHOUSANDSOFU.S.DOLLARS
Fe CONSUMPTION, IN KILOGRAMS PER US$1,000 OF GNP
4020 60 10080 120
10
15
5
0
0
20
25
35
30
Newly industrialized
countries
Developing countries
Industrialized
countries
Possible IOU curve for steel
after technology transfer
IOU curve for steel without
technology transfer
Figure 13.  Intensity-of-use (IOU) factors for steel (in 1990 U.S.
dollars) for three situations for selected countries (Wellmer and
Wagner, 2000). A, IOU factors for steel in 1985. Dashed lines
enclose groups of countries as labeled. B, Possible development
of IOU curve for steel after successful transfer of technology
(dashed line); this hypothetical curve is not observed as shown in
figure 13C. C, Comparison of IOU factors for steel in 1985 and 1995.
Fe, iron; GNP, gross national product.
A
B
C
played down, it must be pointed out that geotechnical methods
are available for proper construction and safe management of
tailings dams. It is a matter of good management and mining
practices to enforce strict quality control down the chain of
command of mining companies. Many companies increasingly
are developing and applying rigorous standardized codes of
conduct to their operations worldwide. Examples of national
and international codes of conduct are those of the (1) Mineral
Council of Australia, (2) International Council on Metals and
the Environment (ICME), and (3) World Bank Guidelines for
Health, Safety and Environment. ICME is based in Ottawa,
Canada. Its members are major international metal mining and
smelting companies.
Rules 3 and 4 of the Enquete Commission state that the
amount and rate of material and energy input into the environment
should not exceed the capacity for their absorption with
minimum detrimental effects. In the context of these rules, the
problem of soils acting as a sink for anthropogenic substances
must be examined. We have to realize that man’s ac­tivities
have considerably increased anthropogenic heavy-metal
concentrations in the soil in and around urban and industrial
areas. An example from the Berlin area in Germany is shown
in figure 14. Another example is the correlation between the
increase of lead in human bones and the increased historical
use of lead by humans shown in table 3 (Friege and others,
1985).
Continued and increased efforts must be made to
devise improved methods for reducing emissions, thereby
protecting our soil so that its capacity to function as a sink
Figure 14.  Contents (median values) of selected heavy metals
in topsoil in urban Berlin and surrounding rural areas (modified
from Birke and Rauch, 1997; courtesy of Encyclopedia of Life
Support Systems Publishers, Oxford, United Kingdom). n, number
of samples; As, arsenic; Cu, copper; Cr, chromium; Ni, nickel; Pb,
lead; Zn, zinc.
MEDIANCONTENT,INMILLIGRAMSOFHEAVY
METALSPERKILOGRAMOFTOPSOIL
150
125
100
75
50
25
As Cu Cr Ni Pb Zn0
Urban areas (n = 1,697)
Agricultural areas (n = 270)
Woodland areas (n = 424)
Global Nonfuel Mineral Resources and Sustainablity   13
14   Proceedings, Workshop on Deposit Modeling, Mineral Resource Assessment, and Sustainable Development
Figure 15.  Comparison of population and worldwide land resources in 1990 and 2010 (Wellmer and
Becker-Platen, 1999).
Population
(in billions)
Forested
areas
(in billions
of hectares)
Pasture and
grassland
(in billions
of hectares)
Cropland
(in billions
of hectares)
Irrigated
land
(in billions
of hectares)
7.03
3.2 3.5
0.28
1.5
5.3
3.4 3.4
0.24
1.4
2010
1990
+33%
–7%
–20%
per capita
change
+4%
–22%
per capita
change
+5%
–21%
per capita
change
+17%
–12%
per capita
change
for pollutants is not diminished. Significant advances have
been made in industrialized countries in the last decade. For
example, a recent study by Thomas and others (1999) demonstrated
that the phasing out of lead in petrol (gasoline)
has led to a considerable reduction of lead concentrations
in the environment. In addition, a recent study by the U.S.
Geological Survey has shown that lead concentrations in
sediments declined as much as 70 percent since the 1970s
and 1980s (U.S. Geological Survey, 1998; Callender and
Rice, 2000).
Concluding Remarks
The process of continually finding new solutions for
the replacement of our nonrenewable resources is governed
by the prices of these commodities and, for mineral
resources, is affected by the cycle of supply and demand
and the effects of learning. In the opinion of the authors,
this process so far has worked in our market economy to
provide a dynamic balance between resources supply and
demand. There is no reason to believe that the process will
not continue to function in the future. Concerning the environmental
aspects and the sink issue, one can be optimistic
that improved technologies will find the necessary solu-
tions.
A more pressing problem for humanity lies in another
area—food for an ever-increasing population. Freshwater and
soil are needed for growing food. In many arid and semiarid
Table 3.  Lead content in human bones.
[From Friege and others, 1985]
Origin of the bones Date
Lead
content1
Reason for lead
content
Inca in Peru A.D. 500–
1000
0.55 No lead used.
Teutones in Bavaria 700–400
B.C.
2.0 Early use of lead?
Augsburg from late
Roman times
A.D.
200–400
4.7 Water pipes, ceramics,
lead food containers.
Augsburg, rich person
from the postRoman
period
A.D. 600 4.5 Luxurious Roman
lifestyle.
Regensburg, poor
person from the
post-Roman period
A.D. 600 1.4 No Roman luxury.
Regensburg, nuns
from the Middle
Ages
A.D.
800–900
2.4 Increasing prosperity
of the cloister.
Regensburg, nuns A.D. 1100 5.1 Use of lead-bearing
tin.
Augsburg, monks
from the Middle
Ages
A.D.
1000–
1200
5.0 Printing presses and
so on.
Modern person A.D. 1983 11–12 Lead in gasoline and
so on.
1
Milligrams of lead per kilogram of bone.
areas today, fossil water is being used. Such water must be
considered a nonrenewable resource when its slow recharge
is measured against its rapid depletion. Huge quantities of
soil, which likewise must be considered a nonrenewable
resource, are lost every year to erosion by water and wind,
thus reducing the amount of arable land. These growing
resource constraints, in combination with an increasing
population, are significantly reducing the amount of arable
land per capita worldwide (fig. 15). This is an historic paradox,
where humanity must be more concerned in the future
with the availability of nonrenewable resources than with
renewable ones.
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