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| Acid
rain: modern chemical threat to marble statues. |
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White marble statues.
That is the image commonly associated with Greek art, but in this section
we shall explore that image deeper. First, there are different types
of marble, as it can be obtained from different sites and different areas
within each site. All these varieties of marble are derived from
the sedimentation (a slow geological rock formation process) of calcite
limestone, and are fundamentally related in that regard. They differ
due to color, texture, weathering, and chemical composition. Yes,
marble it not always white - pure white surfaces were actually avoided
by the Greek sculptors for they often made it difficult to see the soft
modeling (gentle curves) of muscles. The most common color
(going back to the generic image of Greek art) seen in Greek sculpture
is a near white; other colors, used primarily when white marble was inaccessible,
include Laconia red marble and Egyptian granite marble. Another key
factor that sculptors evaluated before they choose a block of marble to
carve was the coarseness or fineness of the marble crystals. A fine
texture enabled the sculptor to achieve greater detail with his work.
But the smaller crystals (of the finer surface) created a duller surface
that was more apt to tarnish by the collection of small particles of dirt
in crevices between these minute crystals. The other extreme choice
of texture was the sculptor's option for a coarse surface, with larger
crystals that showed readily, which imparted a more brilliant surface to
the finished work. The next factor considered in "choice" marble
is how the stone weathers with time. In general the coarser the texture
the less the surface will darken, but other elements are involved in the
weathering especially certain chemical constituents with the marble.
One notable example of chemical weathering can be seen today in the Parthenon
ruins where the once white color of the marble has turned a rust like orange
from the small amount of iron in that particular marble. Unfortunately,
another form of modern day weathering is darkening, which not only changes
the color of the marble, but is actually destroying the ancient works of
the Greeks at an amazing rate (geologically). Acid rain, the infamous
result of a modern transportation infrastructure based on the automobile,
is the major cause of this darkening. The growth of cities and their
use of petroleum fueled cars has only continued to intensify the problem
that leaves no marble statue (ones that are left outside) or building (or
ruin) unscathed. Nothing made of marble that is kept outside
can avoid the wrath of acid rain, which can be easily explained in chemical
terms. Marble, as it is composed of calcite limestone, contains the
element calcium, which makes it a basic compound (basic,
as in the opposite of acidic). Acid rain is formed when water
molecules (such as those in rain clouds) absorb one of two types of sulfurous
compounds, SO2
or SO, two chemicals that result from the burning of gasoline. When
clouds contaminated with these compounds start to rain down on the earth
and the surface of marble sculptures, a chemical reaction ensues that is
analogous to mixing baking soda and vinegar. This reaction actually
eats away some of the marble-- permanently destroying the marble surface.
Efforts to reduce the problem of acid rain (it harms wildlife, plants,
crops, soil, and water supplies as well) have lead to the development of
catalytic converters on cars, which catch some of the dangerous sulfurous
compounds before they exit the exhaust pipe. However, the problem
is far from being eliminated. Most of the chemical differences between
various types of marble are almost imperceptible by ordinary observation,
and are only seen through elaborate chemical testing or X-ray analysis.
These discrepancies are useful today to scientists who study where the
marble was taken from (e.g. the specific site). This kind of information
can then be used to trace the origin of sculptural works and attribute
them (as the sculptors rarely signed their works) to the rightful artist. |
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How can a scientific analysis
of a sculpture attribute it to a certain sculptor? Although
sculpture is usually determined along a stylistic basis, the exact marble
itself can also be the signature a sculptor. The marble itself contributes
to creating the artist's style, since certain types of marble offer unique
possibilities that a artist will learn to master once becoming accustomed
to a specific type of marble. Surprisingly, the three major Greek
sculptural periods (Archaic, Classical, and Hellenistic) drew primarily
only on four sources for their marble: the three islands of Paros, Naxos,
and Thasos, and the site Pentelic of Attica. Other sources were discovered
in later periods, including the immense supply in the Cararra Mountains,
which was mined during the Roman era. The location of an artist also
helped determine the marble he used, because one of the major drawbacks
with marble is difficulty in transportation of the heavy stone blocks.
Thus, many sculptors selected their marble from the nearest site.
If their planned sculpture was sufficiently large, a rough shape (or finished
sculpture) would have to be carved first in order to reduce the weight.
Sometimes marble was totally inaccessible and the next best medium (which
is actually easier to carve) was limestone. Limestone lacks many
of marble's most valuable qualities-- primarily the permanence and beautiful
white color of marble, characteristics that made marble the "choice" stone
for Greek sculptors. Some other medium alternatives included diorite
(a hard black rock), terra cotta (a clay which is strengthened by baking),
topaz, and emerald (green quartz). |
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Marble, the Method of
Sculpting: |
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| The emerging form of
sculpture. |
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During the Renaissance, Michelangelo wrote
of sculpture as the slow release of a form as it emerged out of the stone.
There is no magic involved, but Michelangelo's metaphor captures the essence
of the sculptural art. The form "emerges" with the slow, careful
chipping away the artist performs upon the marble's surface. The
sculptor's magic wand or his "chipping" tools are the hammer, the chisel,
and his meticulous patience . But just chipping away at the marble
leaves a rough surface, which the Greek sculptor smoothed out by abrasion
with another stone called emery (analogous to the way one uses sandpaper
to smoothen a wooden surface). After the surface was smoothed it
was polished with a softer stone to give the once rough surface a shine
known as a patina. Additional treatment of the marble, called
ganosis,
could be perfomed; a temporary (as it had to reapplied to retain its effect)
sealing compound was applied to the surface where it provided an enhanced
smoothness or "glowing" texture. Out of this last treatment evolved
a style and art form in and of itself, called sfumato (Italian for
"smoky"). This style, first employed as a primary consideration in
the Classical sculpture of Praxiteles, relied upon the appeal of excessive
smoothness and modeling, as in the soft shadows formed as light flows across
the gentle contours of the human body. One last method commonly employed
in Greek sculpture is the attachment of the head neck and often arms and
legs by means of pegs rather than relying on the sheer strength of marble,
which as a relatively brittle stone, was always prone to cracking.
These pegs served to reinforce the marble, and also aided in the construction
of a statue, since separate pieces could be worked on at once by several
sculptors, and without the risk of breaking, say an entire arm off by work
details into a hand. Another sculptural tool was the drill, though
it was rarely used by Greeks, it gained importance during the late Roman
Empire (284 - 400 AD), the Roman sculptors, of course, having their stylistic
roots in Greek sculpture. |
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A closer examination of many marble works
reveals faint traces of paint. Today, after over two thousand years,
the mild Mediterranean climate has slowly worn most of the paint off the
sculpture we study, altering our image of what Greek sculpture is supposed
to look like. Now instead of just "white marble statues" we can have
white, red, blue, brown or any other assortment colors that the sculptor
may have chosen. Typically, painting of the sculpture was performed
by a trained painter, not the sculptor himself. The famed Classical
sculptor Praxiteles would produce magnificent works, but they were only
considered complete once they were colored by the popular painter Nicias.
There were no specific rules for painting sculpture, but some general guidelines
can be deduced. Sculpture that was placed high atop buildings, where
the details of the work were less visible to those on the ground, were
painted with bright - almost unnatural - colors. In such instances
discovery of pediment figures with blue beards and orange hair are not
uncommon. For statues placed near the ground more nature or conservative
colors were chosen. The Alexander Sarcophagus, painted by Nicias, displays
this kind of "naturalistic" color scheme: tan hair, light yellow skin,
a purple toga, and a magenta mantle. In some cases the skin is left
unpainted and in almost all cases the eyes, eyebrows, eyelids, and eyelashes
are painted. Hair was also painted on many statues; whenever a coat
of plaster was used to make the hair (it is easier to shape wet plaster
into curls and thin lines than to curve the marble itself) hair was always
painted on to cover the blinding whiteness of the plaster. But usually
before any paint was applied, the dryness of the marble was reduced by
the addition of a sealant which would help prevent the paint from chipping
easily in common hot dry weather. Unfortunately, the effect of the
sealant has gone with the passage of many years, and the paint has chipped
away-- leaving us with "white marble statues" - but even without the colorful
layer of paint the natural beauty of the statue and the stone remain. |
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| Egyptian figures: part
of Psychostasis of Hu-Nefer |
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One
can now imagine a famous Greek sculptor, like Lysippos, methodically hammering,
chipping, and polishing all day inside his quaint little shop; but in fact
few popular sculptors sculpted the finished work . When it
is considered that a single life size marble statue took approximately
one man year to produce (i.e. one sculptor could output one sculpture each
year-- over 3,000 hours of labor), it was not very profitable for one sculptor
to sell just one sculpture a year. What allowed a more efficient
output was the employment of a number of assistants to perform the actual
sculpting by merely copying, into full size marble, the clay originals
made by the famed sculptor. The problem that resulted from this type
sculpting was the lesser skill of the assistants in reproducing the sculpture
on an large scale. There did not exist an accurate method of measuring
the original in order to create and carve the dimensions of a larger marble
version. This lack of a suitable copying method, became a problem
only during in the Classical and Hellenistic periods. And what about
the Archaic period, why no measuring difficulties there? To answer
this last question it is useful to look at Egyptian profile painting and
sculpture. The picture to the left shows a typical Egyptian figure,
the pose, the hair, the clothes are all probably familiar to anyone who
has seen Egyptian art before-- almost all Egyptian figures look exactly
the same! A German, Irwin Panofsky, looked at this similarity and
with the aid of mathematical analysis, he found that the head of any Egyptian
figure was always say one seventh the total height, the waist about one
fifth the total height, the arms… and so on and so forth. In other
words, he discovered that all the parts of the figure were created according
to a specific and rarely altered system of proportions. In fact,
it is believed that the Egyptian artists would draw a grid of evenly spaced
horizontal and vertical lines over the area they were to sculpt or paint
and that they would use the spacing between each line to accurately define
their proportions. This same grid system was applied to Greek Archaic
sculpture, and it produced the rigid sculptural forms of that period.
The Greek sculptor would actually draw such a grid of lines of two opposite
sides of a block of marble. After drawing the grid he would carve
each square down to a certain pre calculated depth, finish both sides and
round out a transition from back to front for the profile. This simple
system produced a simple and limiting style, as can be seen in the similarity
of almost all Greek Archaic sculpture. |
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By
480 BCE, as the Archaic style lost popularity, the Greek sculptor demanded
more from the marble. And as more complex forms were created the
process of grid coping was no longer feasible. A method similar to
that of the grid system was employed by the Classical and Hellenistic copiers,
where a number of "points" on the original clay model would be measured
and then multiplied in size according to the factor of enlargement.
These modified measurements would then be drawn onto the marble block,
and like the grid (where each square was carved down a certain depth) each
point would be carved to a specific depth. But with this crude technique
only a limited number of "points" could be measured, creating a final marble
copy that was only a rough approximation of the original clay version made
by the sculptor. It is known that the clay originals of one particular
sculptor (Arcesilaus, first century BCE) would sell for more than the finished
marble versions his assistants produced and even more than the finished
versions of contemporary sculptors-- showing that copies, for their poor
quality, and also for the indirect touch of their original artist, were
not the favored from of sculpture by those wealthy enough to be picky (it
should not be forgotten that monumental or life size marble sculpture was
an art form for the upper class members of Greek society). |
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| Doryphoros,
copy. |
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The
grid system disappeared as the Archaic period ended, but the idea that
the human form can have a mathematical basis was not forgotten. It
was Polycleitus, with his Doryphoros, which was comprised of his
"New Canon* of Proportions," who renewed and innovated the idea.
Defined upon the mathematical laws of proportion, Polycleitus' system did
not depend on what was en vogue, or popular-- it depended on careful observation
of the nude human (particularly the male nude). Thist may sound unusual
but that is what most Greek Sculpture is: nude, Greek, and male.
And during the times of ancient Greece the most common and popular public
events were the athletic competitions in which nude males primarily participated.
Thus knowledge of the human form in the purest sense (i.e. nude athletes)
was very common to the Greeks (even though today modern society is not
quite as knowledgeable about that sort of thing and such athletic events
are probably illegal). So is may not seem surprising that Polycleitus
was considered the master of athletic statues. The set of proportions
formalized by Polycleitus played a key role it the subsequent periods of
Greek Classical sculpture that followed as it permitted the "naturalization"
tendency to further develop, culminating with the "dramatic" sculpture
of the Hellenistic period. As art historian Gisela Richter writes:
"...proportion is the element that redeems naturalistic sculpture, preventing
it from becoming merely representational."
* "Canon" is defined here
as a specific set of rules or guidelines.
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