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Furthermore, as the temperature factor is that which is most relevant (the chemical
composition of the surrounding environment not relevant at all) the chosen base-
line should include this parameter. Nevertheless, if the system under analysis is a
mineral deposit, say of copper, the ambient temperature does not affect its quality.
In this case, it is the composition and concentration of the surrounding land which
distinguishes it and makes it valuable.
So which should be the optimal and most coherent baseline for the assessment
of mineral resources?
10.2.1 Entropic versus commercial death of the planet
The Clausius formulation of the Second Law, where “the entropy of the Universe
tends always to a maximum”, is another way of stating that the universe tends
towards a thermal death. Hawking (1988) demonstrated that the principle of in-
creasing entropy is obeyed even in black holes.
Yet the baseline initially sought for in this topic is not like the thermodynamic
death of the universe imagined by Clausius. To visualise this, one can compare
the “entropic death” of the Earth with that of Venus, a planet with an atmosphere
composed of 95% CO
2
with all materials of its crust having mixed and reacted
until upon reaching the minimum reactivity level under the existing conditions of
the planet. It is however impossible that the Earth would ever reach that extreme,
as it is the proximity of Venus to the Sun which increases its temperature and
favours melted and gaseous states. The energy barriers of activation which are
surpassed and the reactions that occur would simply not be possible under normal
Earth conditions.
At the relatively low temperatures experienced on Earth, most of the constitu-
ents contained in the crust are in their solid state with the only major exception
liquid water (essentially inert at ambient temperature). The most important che-
mical action in water is the solution of substances, whilst that of air is oxidation
in a typical low-temperature solid-gas reaction, which is itself impeded by its own
dilution of oxygen (the convection flows that provoke mixtures or homogenisation
mostly occur in the hydrosphere and atmosphere). Furthermore since the appear-
ance of multi-cellular life, 550 million years ago, the composition of the atmosphere
has fluctuated only slightly. Oxygen, for example, an extremely corrosive gas, di-
luted in the atmosphere by 79% nitrogen and other minor gases at ambient tem-
perature, has remained stable at around 21%. In other words, it is the relatively
large distance from the Sun which has been the predominant factor in preventing
the entropic degradation processes that occur on neighbouring Venus. At the same
time, it is the relatively short distance from the Sun that has favoured the appear-
ance of multi-cellular life, by maintaining those physical and chemical conditions
that allow for the existence of carbon, nitrogen, water and material cycles, which
in turn makes this planet universally unique.
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