The Search for Metals, the Search for Reason

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The Search for Metals,the Search for Reason
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Metals in the Ancient World

• Copper - native element
• Tin - native element, or as impurity in copper
• Gold - native element
• Silver - native, or with galena or copper
• Lead - as galena
• Iron - meteoric origins, with nickel impurities

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Metals in the Ancient World

• Sulfur - native element, or condensation during
  smelting
• Arsenic - from realgar and orpiment
• Zinc - from zinc sulfide or blende
• Bronze - harder, but easier to work alloy of
  copper and tin
• Brass - alloy of copper and zinc
• Pyrites - copper or iron sulfides that spark when
  struck

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Gold is where you find it
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Lead is important, too. Galena crystals are lead
and sulfur.
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Very few materials are useful in their raw form.
This is Copper Carbonate (Malachite and Azurite)
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Native Silver
Native Copper
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Sulfides, Oxides, and Carbonates form common ore
minerals.
Chalcopyrite - CuFeS2
Galena - PbS
Covellite - CuS
Sphalerite - ZnS
Pyrite - FeS2
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Transitions

• During the late Neolithic period, the utility of
  metals was discovered
• The first such metal was likely copper, found as
  a native element
• Copper was easy to pound into shape but became
  brittle without annealing - the Chalcolithic
  period
• Gold also shows up, but as an ornamental material
  - it was too soft to use in tools, but easy to
  work.

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Ötzi, the Iceman
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Transitions

• Copper could not be melted - wood fires could
  only reach 600 degrees F, but copper melts at 800
  degrees F, and 1000 degrees F are needed to
  purify copper
• When mixed with tin, it was possible to melt the
  two together and produce an alloy that is harder
  than either copper or tin
• Ushered in the Bronze age - not great for hard
  work, but useful for plowshares, pruning hooks,
  swords, and spearpoints.

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Where was it found

• Placer deposits - as concentrated by moving
  water
• Vein deposits - present, but considered
  supernatural in origin, as the work of gods or
  demons
• The search for origins led to the search for
  knowledge.

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Placer deposits work by having running water
concentrate ore minerals.
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Iron Age

• With the use of bellows to pump in air, the
  temperature of a fire could be increased,
  allowing people to smelt other metals from their
  ores
• The release of iron from (likely) pyrite
  revolutionized the ancient world, starting in the
  Middle East (and separately in Britain)
• The new metal was harder to get, but harder than
  bronze. Much harder.

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Iron Age

• The properties of iron could be manipulated by
  working it over and over again, to remove
  impurities and introduced a critical level of
  carbon
• The result was steel
• The Roman Empire took full advantage of this
  material, likely originating from Iberia (Spain)
• But there was always a hint of the unexplained in
  steel

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Metals and Mysticism

• Metals have always been something of a mystery
• Agriculture was always managed by humans, but
  metals could not be, or so it seemed
• As a result, metals were considered donum dei, or
  a gift of the gods
• In order to understand the gods, the
  semi-religious study of the gifts of the gods
  began, which became alchemy.

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The Riddle of Steel

• Fire and wind come from the sky, from the gods of
  the sky. But Crom is your god, Crom and he lives
  in the earth. Once, giants lived in the Earth,
  Conan. And in the darkness of chaos, they fooled
  Crom, and they took from him the enigma of steel.
  Crom was angered. And the Earth shook. Fire and
  wind struck down these giants, and they threw
  their bodies into the waters, but in their rage,
  the gods forgot the secret of steel and left it
  on the battlefield. We who found it are just men.
  Not gods. Not giants. Just men. The secret of
  steel has always carried with it a mystery. You
  must learn its riddle, Conan. You must learn its
  discipline. For no one - no one in this world can
  you trust. Not men, not women, not beasts.

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Metals and Mysticism

• In Hellenistic thought, this was the goal of the
  Pythagoreans, Ionians, and Gnostics
• That is, to understand the divine, there were
  but a few rules, mathematically based, and to
  learn these rules was to approach the perfect (or
  salvation)

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Faith and Thought

• Augustine was antagonistic to experiments to this
  end, strongly urging reason and faith over
  experimentalism
• There is also present in the soul, by means of
  these same bodily sense, a kind of empty longing
  and curiosity which aims not at taking pleasure
  in the flesh but at acquiring experience through
  the flesh, and this empty curiosity he is
  dignified by the names of learning and science.
• Direct observation was discouraged to the point
  of being a crime - To conduct direct observations
  of human physiology was evil, as Galen (in the
  Greek world) had defined it all by reason
  without observation.

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But Aristotelian thought did not simply go away

• Preserved by the Islamic world, experiments and
  direct observation were the rule, rather than the
  exception
• With the invention of the printing press, ideas
  which could be suppressed were now made available
  to a larger audience, in such a wide manner that
  they could not be suppressed.
• The work of Copernicus replaced the Ptolemaic
  model of the Solar System through a theoretical
  model, based on observations of the night sky
• The work of Versalius replaced Galen as the means
  by which to practice medicine through observation
  rather than dogma.

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Alchemy

• Alchemy has its origins in the ancient world,
  from the Arabic al-khimia, as an effort to
  understand both the corrupt and degenerate world
  and the divine
• As a result, the two main concerns were the
  transmutation of common metals to precious metals
  (or spagyrics) and the creation of a cure for
  disease and life-prolonging agent (or panacea)
• The search for both of these elements represented
  the evolution from the profane work towards the
  divine, incorruptible world
• The philosophers stone was the alleged key to
  this search.

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Alchemy

• Alchemy always enjoyed a mixed reputation
• On the one hand, it promised a long and wealthy
  life
• On the other hand, it challenged the authority of
  God, and thus the theocratic basis of government
  
• It also threatened to destabilized economies with
  a flood of easily obtained precious metals.

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As a result,

• Alchemy was publicly discouraged, or even
  suppressed (Diocletian, Pope John XXII), while
  privately it was encouraged by patrons and
  engaged in by the sharpest people of the day,
  including Roger Bacon, St. Thomas Aquinas, Tycho
  Brahe, Robert Hooke, Isaac Newton, among others
• Aquinas in particular claimed that universal
  truths could be discovered only through logical
  reasoning, and as reason was a gift of God, then
  it could not be in opposition to God
• This ran contrary to the Platonic ideal that such
  truths could be found through divine insight
  alone.

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Language

• An entire lexicon was developed from common
  observations of behavior or use, in the absence
  of an independent language
• Sugar of lead lead acetate, used by the Romans
  as a sweetener
• Oil of vitriol sulfuric acid
• Aqua fortis nitric acid
• Aqua vitae concentrated ethanol
• Aqua regia royal water, a mixture of nitric
  and sulfuric acid, capable of dissolving gold
• Pyrite fire stone
• Quicksilver mercury, as the juice of cinnabar
• Verdigris Copper carbonate hydroxide

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The Medical Connection

• The most learned people of the day were trained
  physicians
• Neils Stenson (Steno) was trained as an anatomist
  and dissectionist
• Georg Bauer, publishing under the name of
  Agricola, was also a physician
• In searching for the old alchemical goals,
  especially the panacea, the physicans turned
  towards mineralogy both as a cure for disease
  and old age as well as an epidemiological issue
  among miners.

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Georg Bauer - Agricola

• Born in Glauchau, Saxony, 1494
• Entered University of Leipzig, 1514
• Further study at Universities of Bologna, Padua,
  and Ferrara, obtaining a medical degree
• Returned to Zwickau in 1526, then moved to
  Chemnitz in 1530
• Died 1555

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Chemnitz
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• Intense period of religious upheaval in central
  Europe, with Protestants (Lutherans and
  Calvinists) fighting for political power with
  Catholics
• Several small wars broke out during this period,
  particularly over who could or should interpret
  the Bible
• Agricola largely steered clear of these
  arguments.

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• Agricola put aside the classical ideas, tied to
  Biblical accounts and Aquinian logic, stating
• those things which we see with our eyes and
  understand by means of our sense are more clearly
  to be demonstrated than learned by means of
  reasoning.
• which refuted many scholastic beliefs.

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Agricolas body of work

• De ortu et causis subterraneorum
• Subterranean caverns
• De natura eorum quae effluunt e terra
• Natural juices and fluids of the Earth
• De veteribus et novis metallis or
• De Natura Fossilium
• De animantibus subterraneis

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Observations

• His observations included topography, vegetation,
  and Earth events
• They also included taste
• salty salt
• nitrous soda
• aluminous alum
• vitrioline vitriol
• sulphurous sulfur
• bituminous bitumens

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Mineralogy of Agricola

• In De Natura Fossílíum, Agricola described and
  categorized about eighty minerals in terms of
  their physical properties -- color, brilliance,
  taste, shape, hardness, solubility, fusibility,
  etc.
• Agricola classified minerals into one of five
  categories based upon their physical properties
  "earths" such as clay and chalk gems and
  precious stones "solidified juices" such as
  salt, alum, orpiment, and sulfur metals and
  "compounds" such as pyrite and galena.
• Until the elucidation of atomic theory 450 years
  later, this text was the standard for mineralogy
  if you could get a copy!

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De Re Metallica

• Published in 1556, it consisted of 12 books and
  over 200 woodblock prints
• Mining and metals were not to be thought of as
  intrinsically evil, but of utility to man
• Published the year after Agricolas death, it has
  remained a definitive text in geologic and mining
  engineering
• Originally in Latin, it was translated into
  English by Herbert Hoover and his wife in 1912.

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De Re Metallica

• Agricola departed from the alchemical model, by
  separating the practical knowledge of miners from
  the mystical
• Metals were found not by divination but by
  observation of the physical conditions in an
  area, both above and below ground.
• If we see similar conditions in other areas,
  then there is a high probability of finding the
  metals that you seek there.

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De Re Metallica

• The geometric orientation of veins, their
  thicknesses and distribution was important
• Topography and ground cover also provided a clue
• Associated minerals or colors also gave
  indication of the metals of interest
• But the nature of the juices issuing from the
  Earth could also concentrate metals my moving
  water, or by dissolved in them and determined by
  taste
• The juices were not of mysterious origin, but
  were also characterized by their source and
  behavior, solidifying or dissolving metals on a
  thermodynamic basis.

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Minerals described

• Copper 5 types
• Lead 8 types
• Tin 2 types
• Antimony 2 types
• Bismuth 1 type
• Mercury 2 types
• Arsenic 4 types
• Iron 12 types
• Cadmia includes zinc, cobalt, and arsenic

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The Joachimsthaler

• In 1518 Bohemia, a part of the Holy Roman Empire,
  a coin was minted and named the Joachimsthaler
  from the silver mined near Joachimsthal (St.
  Joachim's Valley, Czech Jáchymov) (now in the
  Czech Republic)
• Thal (Tal) means "valley" in German. Joachim, the
  father of the Virgin Mary, was portrayed on the
  coin.
• Similar coins began to be minted in neighbouring
  valleys rich in silver deposits, each named after
  the particular 'thal' or valley from which the
  silver was extracted. There were soon so many of
  them that these silver coins began to be known
  more widely as 'thaler'.
• From these earliest 'thalaer' developed the new
  Thaler - the coin that Europe had been looking
  for to create a standard for commerce

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Legacy of Agricola

• Despite being a product of his time and thus
  subject to the prejudices of the day, Agricola
  produced the first body of comprehensive
  literature on the origins as well as the
  descriptions of Earth materials
• Even though some ideas are obsolete (fire-facing
  in mines) or naïve (Earth juices), they are based
  on solid observational footing that is useful
  from place to place
• In short, Agricola established the descriptive,
  explanatory, and predictive basis for geology.