The stone carver's tookit was stable for an astonishingly long period of history. Between the Classical Period of Greece, starting in the mid-Fifth Century BCE, and the late Nineteenth Century, the basic tool kit had evolved hardly at all. Only in the last hundred and twenty years, with the introduction of power tools, and ultra-hard materials such as tungsten carbide and carborundum5, has the sculptor's tool kit expanded significantly beyond what was available to Phydias, during the building of the Parthenon. Even today, more than a century into the era of power tools, while the tool set has been augmented, all but a few of the old tools remain in use. A Twenty-First Century sculptor would be familiar with almost everything in Phydias's tool bag except bow-powered rotary drills and grinders, which have been replaced by power tools that do much the same thing faster, with less effort. The extraordinary stability of the tools and media, and the simplicity of the process, give us a rare chance to look at the aesthetic intentions of each age, without the confounding factor of the available technology.
The illustration below shows the basic tools of a mid-Fifth Century BCE Greek sculptor. These illustrations are not drawn from ancient Greek artifacts. Although a handful of illustrations of sculptor's tools dating from the period exist, no sculptor's tools from ancient Greece are known to have survived6. Instead, most of what is known about the ancient tools is inferred from the the tool-marks on datable sculpture and architecture, and from the known capabilities and limitations of the metallurgy of the various periods. While the sculptor's tools have been lost, weapons and other artifacts from the ancient world are abundant, and give us a very good idea of the metallurgy of the ancient world. There are numerous extant examples of the marks of every kind of tool, and every stage of carving, from uncompleted sculptures, portions of sculpture left rough because they were not intended to be exposed, and from architectural stonework, which required a closely related tool set. While some interesting arguments remain, a great deal of evidence survives to give modern scholars a good idea of what tools existed when.
The tools in use prior to the 20th Century fit into just a few categories:
The status of one class of tools remains in doubt. Scholars disagree on the extent to which mechanical aids to copying and measurement were used in the ancient world. Some simple techniques are known to have been used in the Classical period, and it is almost certain that more advanced techniques were employed in subsequent Hellenistic period, but whether these advanced techniques were used by Classical sculptors is subject to debate. However, while their use in the Classical era is not certain, it would be remarkable if sculptors in the era between Pythagoras and Euclid were not aware of the geometric principles underlying the use of triple calipers. We have a very good picture of how quickly these techniques can be developed from the example of the Renaissance, when Italian sculptors developed a range of scaling and copying techniques within a few decades of the beginning of the resurgence of interest in Classical styles.
A few varieties of stone, like steatite (soapstone), and alabaster, can be whittled with an iron or bronze knife, or even with a stone or bone tools, and are thus always considered soft. At the other extreme, granite, basalt, diabase, and porphyry are difficult to scratch even with the best quality modern steel, and are thus always categorized as hard. All forms of limestone and marble, by far the most important stones to sculptors, are between these two extremes, and are thus categorized as "medium hardness." Some varieties are harder than others, but all medium hardness stones can be worked with steel tools. However, marble is on the borderline for carving with bronze and wrought iron tools. These metals are not hard enough for some fundamental marble sculpting tools.
A few fundamental properties of stone determine most of the techniques of carving. First, stone has tremendous compressive strength, but little tensile strength, i.e., is hard to crush, but relatively easy to pull apart. For instance, the tensile strength of marble (although it varies slightly with the variety) is about 50.6 Kg/cm2 (720 psi), while the compressive strength is around 1120 kg/cm2 (19,000 psi). Equally importantly, unlike metals, stone has only the most minute ability to bend, stretch, or deform; if you if you hit it hard enough to exceed its compressive strength, it doesn't dent, but is crushed to powder. If you exceed it's tensile strength, it stretches only microscopically before it simply parts.
Stone working tools take advantage of these properties in different ways. One of the simplest techniques for working stone is to strike the surface with something even harder, such as a ball of hard stone, shaped to concentrate the impact, in order to pulverize a spot on the surface. Modern bush hammers do the same thing, but with an array of pyramids to crush several spots at a time. Abrasives also remove stone by pulverization, but do so from countless tiny points of pressure at once. Each of many hard corners of the abrasive grains apply intense pressure to a microscopic area, pulverizing a fine scratch across the surface, together wearing away the surface a fraction of a millimeter at a time.
Tools such as punches, which penetrate the stone to split away chips, pulverize a small amount of stone as they penetrate the rock, but the stone they remove in this way is incidental. The penetration is primarily a means to take advantage of the stone's low tensile strength. The stone beneath the tip of a punch is crushed by the concentrated pressure of the tip, but the sides of the spike spread the outward pressure over a much broader area, and acting as a wedge, burst loose much larger, more or less intact chips. The punch is most often used at a low angle to the stone, and the chips thrown outward, perpendicularly to the direction of the hammer. It can also be used straight-in, at a right angle, in which case the chips are ejected backwards, from all around the tip.
Note that the outward pressure of the punch does not have to exceed the tensile strength of the entire area of the chip--the rigidity of the stone concentrates the outward force at the leading edge of the crack. A propagating crack is like the tearing of cloth: a tear is difficult to start, but once it is started, any further pulling force is focussed on the few threads at the leading edge of the tear, allowing it to propagate with little more force than is required to break the next single thread. The boundaries between crystals tend to interfere with the propagation of tiny cracks, and limit the concentration of force at a crack's leading edge, toughening the stone. To extend the cloth analogy, discrete crystals act like the extra strong threads that are interspersed in rip-stop nylon. Glass (e.g., obsidian) is the most extreme case. Glass has high tensile strength (which is why fiberglass is used to reinforce plastic resins) but its uniform and non-crystalline nature allows outward force to be so concentrated that a crack, once started, propagates almost effortlessly, which makes glass more or less uncarvable, except by grinding. Almost all other stones have significant crystalline structure7.
Edge tools, driven straight-in, also work by exceeding the tensile strength of the stone, but they are not used to pop away superficial chips. Heavy chisels used in this way crush their way into the stone for only a very short distance, after which the wedging pressure to the side becomes so great that a large chunk can be split from the stone. As with a punch, the leading edge crushes into the stone, starting fine cracks, but the broad sides behind the edge diffuse the outward force over too large area to crush. Thus, much of the force of the hammer is delivered outward, to the side, against intact stone, allowing a relatively small force to crack loose a large amount of waste.
Edge tools driven in at an angle, on the other hand, are mainly for finer carving. They are designed to shave away a thin layer, usually the uneven stone left behind by a penetrating tool, such as a claw chisel. This action is very different from the right angle stroke in that, ideally, it produces mostly powder and chips of negligible size. When carving marble, producing chips with the oblique chisel stroke tends to be a bad thing, because part of the mass will often be pulled from beneath the otherwise smoothed plane of the chisel's passage, leaving irregular pitting.
Wedges also split stone with outward pressure, but they don't bash their way into the stone by force. Instead, they are placed in a rows of pre-drilled holes, and the outward pressure slowly increased across the entire row. A handful of wedges, tapped with a two pound hammer, can split a stone the size of a car. Stones that have a very pronounced layering can sometimes be split effectively by driving hardened wedges directly between the leaves, but this used mainly by masons, not sculptors.
Pitching tools look superficially like chisels, but actually belong to a class of tools they do not deliver outward force to the side, the way chisels and wedges do. Instead of having an edge, these tools have a flat face that is designed to push directly on the stone, transferring the hammer energy to the stone without significant penetration. When driven against the stone at an angle, the corner of the face bites into the block a millimeter or so, allowing the flat face to deliver the hammer's momentum in line with the swing, to propagate the minute cracks that were started by the sharp corner. Pitching removes a lot of stone quickly, but it only works from the outer edges, and is thus most often used applying a rusticated surface of broken stone to the face of a squared block.
Gold, silver, and copper have been in use since before the historical record, but these metals are very soft. The discovery of bronze, an alloy of copper and tin that is much stronger than either metal alone, ended the Copper Age, and revolutionized society across the Mediterranean when the technology was developed sometime around 3300 BCE. Bronze was was the first metal of which reasonably hard tools could be made8. The weapons, armor, and tools that bronze made possible, as well as the resulting trade, not least, the trade in the metals themselves, propelled the greatest social revolution since the development of agriculture made cities possible.
Bronze is a relatively easy metal to work with because the component metals, copper and tin, can be smelted from ore at easily attainable temperatures, and the liquid metal can be cast directly into usable shapes, by pouring it into molds. Unfortunately, even the best bronze is a marginal material for stone-working. It can be made just hard enough to penetrate marble, but not hard enough to support the full range of techniques for working stone. Bronze tools can penetrate marble only when driven at a right angle to the surface, but they are not hard enough to bite into the stone, and tend to skid off of the surface when driven obliquely9.
The discovery of techniques for manufacturing and working iron, which had once been more precious than gold, began in the Mediterranean world sometime between 1200, BCE and 1000, BCE10, but the complex and difficult metallurgy of iron ensured that that bronze would remain superior to iron in almost every respect for many centuries more. Until steel making was mastered, iron's chief virtue was that it was cheaper and more abundant than bronze, which remained superior to iron in almost every way.
Steel is much harder to make than bronze or carbon-poor iron, and harder to work with. The iron in iron ore is in the form of various oxides--rust, basically--mixed with various other minerals. Smelting iron from ore requires a temperature high enough to liquify the metal. This temperature is far higher than the melting point of tin or copper, and is difficult to achieve with primitive technology. However, with the right ores, wrought iron can be made at a temperature lower than is needed liquify the metal11.
Unalloyed iron is as soft as aluminum, but when a small amount carbon is added, it becomes steel, which is much tougher, and equally importantly, can be both hardened and softened with heat-treatments. Small amounts of other metals can also be added to the alloy to enhance various properties, but carbon is the key additive. Copper and tin, mixed together and heated, automatically yield bronze, but steel requires significant chemistry, at extraordinarily high temperatures, combined with a very specific sequence of physical and chemical manipulations of the evolving product. If making bronze is like making soup, then making steel is more like making mayonnaise. With too little carbon, the metal is softer than bronze; with too much carbon, the metal can be broken up with a hammer. Moreover, unlike bronze, which is easy to cast into usable shapes, malleable iron and steel are usually forged, i.e., heated red-hot, and beaten into the desired rough shape. The rough forged blank must then be softened with heat treatment, after which it can be milled, filed, and ground to the final shape. Finally, the finished object must subjected to a series of post-manufacture chemical and heat treatments to harden it for use.
The most technologically accessible techniques for making steel involve laboriously adding carbon to soft iron while it is in a solid state. The most important way of doing this was by allowing carbon from charcoal to soak into the surface of the hot iron, then repeatedly hammering the bar flat, folding it, and forge-welding it back together, until the sufficient carbon was dispersed throughout the metal12 Steel good enough to work stone was probably too expensive to waste by making an entire tool out of it. Although no carving tools of the period have survived, it is likely that high-quality steel would have been conserved by forge-welding13 hardened steel implants into soft iron tool bodies, a process which was still common well into the 19th Century, and continues to be used today in the best Japanese hand tools. Steel manufacturing took centuries to master, and was reinvented several times, having appeared in both East Africa and Turkey as much as a thousand years before it appeared in useful quantities in the Greece, at the end of the Archaic Period, in the late Sixth Century BCE.
The precise date at which the full modern tool set appeared (implying the use of steel) is not known, but Sheila Adam's comprehensive study of Greek carving in 1966 fixes a loose lower bound at sometime the late Sixth Century BCE14. Greek sculptors at the beginning of the Early Archaic Period (app. 660 BCE to 580, BCE) certainly lacked steel tools, and were limited to bronze and wrought iron. Carving at the beginning of this period was therefore accomplished without the use of modern chisels, and sculptors relied primarily upon the punch, driven directly into the stone at a right angle, for marble sculpture. These early sculptors gradually reduced the block, more or less evenly from all four sides, by punching thousands of shallow craters into it with the punch.
The punch marks are distinctive. Each crater is roughly conical, with the inner face broken, rather than crushed, with a puncture-mark at the bottom. As the stone neared it's final form, a progressively lighter touch was used, producing smaller and smaller craters in the stone15. At any given point in the process, the entire sculpture was completed to approximately the same degree on all sides. The final smoothing was accomplished by manually grinding the punched surface with stone or emery16, a process which seems unimaginably laborious to a modern carver.
Fortunately for historians of art, several examples of unfinished Archaic Period carvings in various stages of completion have survived. It can be inferred from these examples, as well as from the appearance of finished pieces, that Archaic sculpture was generally executed from rectangular blocks, apparently without mechanical measuring devices. These blocks were often roughed out at the quarry to reduce the weight before shipping. Blüemel [Blüemel 48] cites a number of examples of roughed out pieces that for one reason or another never made it out of the quarry, and lay where they were abandoned until modern times. Drawings on each of the four vertical sides were projected through the block by punch-work, almost as if the roughed out sculpture had been cut out of a rectangular block using a band saw, first from front to back, and then from side to side. The result was that in the early stages, in any horizontal cross section, the front, back and sides of the sculpture were parallel respectively to the front, back, and sides of the original block.
Both the surface qualities and the form of Archaic Greek sculpture reflect the simplicity of this carving technique. The figures are simple and monolithic, with hands and arms attached to the body, and both feet on the ground. Detail tended to be superficial as seen in the picture above.. The four sided approach propagated all the way to completion. Archaic figures, particularly male figures, tend to be designed for four viewpoints, corresponding the original four sides of the block. The use of the straight-in punch is at least partly responsible for the simplicity and generally monolithic nature of Archaic sculpture for two reasons. The first is that the punch cannot be used straight-in on unsupported stone. The most natural way to work around this limitation is to keep all the masses connected to the core of the statue. The second is that the straight-in stroke is inherently coarse grained. Even with a light touch, the punch leaves a puncture of variable depth in the otherwise undisturbed stone at the bottom of the crater, below which there was insufficient sideways pressure to rupture the stone. The distance from the punched surface to the bottom of the deepest punctures is the closest the punch-work can get to the finished surface, and to get even that close takes a lot of punching, with the number of punch holes increasing rapidly as they get closer together17.
Unworked marble is normally translucent. A direct impact produces a region of microscopic cracks under the point of contact, causing a permanent milky opaque cloud in the stone, extending to a depth of as much as 1/2 inch or more, depending on the kind of stone, the shape of the object hitting it, and the force of the impact. Bruising has been carefully avoided by most marble carvers since the Renaissance, but ancient carvers usually deeply bruised the stone all over by punching straight-in, and therefore, Greek marbles typically have a soft, matte, opaque appearance, more similar to limestone than to the luminous translucence of modern marble sculpture.
The effect of bruising is more than cosmetic. Bruising is a mechanical disturbance of the integrity of the stone that makes the surface softer and more absorbent, and therefore more susceptible to the effects of weathering. A record of the cratering process can actually re-emerge on pieces that were once smooth, when they have weathered, as the deeper bruised areas will erode more quickly. However, bruising had at least two desirable effects for ancient carvers: first, it probably made the laborious process of smoothing easier, and second, the more porous surface would have been more receptive to paint and other coloring treatments that were customarily18 applied to almost all white marble in the ancient world. The illustration below shows what Classical Greek carving looked like at the time of its creation, as imagined by the Victorian painter Lawrence Alma-Tadema. It depicts Phydias showing his new work on the frieze of the Parthenon to a group including Pericles, Socrates, and their respective lovers, Aspasia and Alcibiades.
It is known that the basic steel tools, which had first appeared in the Archaic Period, were fully developed prior by the beginning of the Classical Period, which nominally began in 480 BCE, with the Greek victory over Persia.
The evidence of tool marks and sculptural styles, suggests that the emergence of the full range of uses of the tools was a gradual process driven by the evolving metallurgy. Despite clear evidence that all the basic tools existed as early as the Sixth Century BCE, the punch, for instance, continued to be used in the old way throughout much or all of the Classical period20. Also as in the Archaic Period, it remained characteristic of the Classical Period that pieces were worked on from all around, and at any given point in the process, were finished to a more or less uniform degree on all sides.
Classical sculpture was apparently executed without direct mechanical copying, but plumb-lines and measurement from models are known to have been used, and can be seen in surviving illustrations of artists at work [Blüemel 48] pps. 48,49. The greater complexity, originality, and naturalism of sculpture made preliminary models essential, but the sculptor's primary reference at the level of the hammer stroke appears to have remained the the evolving work itself, rather than a reference point transferred from a model.
The work of the Classical Period, though more natural and expressive than the Archaic style, still reflects the limitations of the carving tools to some degree, in the softness of the curves and in the relatively simple compositions, as seen, in The illustration below , Dionysus reclining, originally from the pediment of the Parthenon, and carved at the apogee of the Classical Period. Even when figures appear on groups, in this era, as in pediment figures, they still retain some of the old monolithic spirit.
With the more capable tools introduced in the late Archaic period, the standard sequence ceased to be punch followed directly by grinding, as the practice had been in the early Archaic Period. From the late Archaic on, punch work was followed by further superficial carving with the claw chisel, sometimes progressing on to flat chisels and roundels, or bull-nosed chisels, prior to grinding. Both finished and unfinished Classical Period carvings showing the full progression of tool marks still exist.
One of the things that is most striking to a modern stone carver is how much the drill was used by ancient carvers, and indeed, continued to be used until the early Twentieth Century. In the last century, pneumatic tools and rotary grinders have taken over much of the work that was once done with drills.
Ancient carvers made extensive use of several kinds of drills that worked by at least three different mechanisms: (1) grinding a hole into the stone by rotating the bit, like a modern drill (2) wearing a hole into the stone by tapping--the modern equivalent is a star drill (3) grinding a slot with a rotary bit applied to the side.
Drills in the ancient world could be as simple as rods tipped with flint or metal, that were twirled between the palms21 or twisted like a screwdriver, or metal bars with a chisel-like end, that were tapped with a hammer as they were turned, to slowly wear a hole into the stone. Braces, i.e., drills turned directly by a crank that is inline with the bit, were known to the Greeks, but these turn at low speed, and are usually more effective at driving augurs for boring wood. More complex mechanisms, turned with a cord or strap, were standard equipment for stone carvers in the Classical age. Bow-powered rotary tools were common as late as the middle of the Twentieth Century, for both wood workers and stone carvers22, and are known to have been used by workmen of the Classical period, because their use is depicted in a number of art works, although no images exist of them specifically being used on stone. The use of strap powered tools, similar to bow powered tools, but operated by one worker while being turned by another, can be probably be safely inferred, because the size of many of the holes exceeded the size what can be achieved by a bow. Smaller bow drills from recent times often have a handle at the top for applying pressure, while larger drills usually have a chest-pad that the user could lean on. Greek engineering of mechanical devices was unsurpassed for many centuries, so it is unlikely that they did not develop these obvious refinements, and very likely others as well.
Drill bits made of both stone and metal were used, and the Mycenaeans, in the Second Millennium BCE, as well as the Egyptians more than two thousand years earlier, even used tubular copper bits23 that sawed out a circular plug, although this method seems not to have been used by the more modern Greeks. The most common bits used in the Classical period were steel, with flat or rounded chisel-like tips. (The shapes of the tips are evident from the marks that remain.)
The rotary drill was used extensively for a variety of purposes. In addition to its use for making round holes for nostrils, ears, etc., and for affixing attachments, it was heavily used for outlining the masses, and for removal of stone from tight spaces, such as between folds of drapery. In this mode of employment, the stone would be honeycombed with holes so that it could more easily be removed with chisels and rasps.
From the Classical Period on, the running drill was heavily used as an aid to carving deep grooves, particularly the long vertical folds of drapery, but also in hair and elsewhere. The running drill was not really a drill in the modern sense, but more similar in function to a die grinder, in that it was not used to drill round holes, but to cut a channel. No pictures of ancient running drills are known, but it appears to have been turned by a bow or pulley arrangement, similarly to a drill, with the bit being pushed or drawn along the surface as it turned, cutting a shallow groove that was deepened and widened by successive passes. Though now extinct, this tool, like the bow drill, was in use as recently as the early Twentieth Century.
The running drill is believed to be the only carving tool used in Classical Greece that did not yet exist at the end of the Archaic period. Blüemel [Blüemel 48] states that the running drill was in use in the middle of the Fifth Century BCE, but a considerably later date of 370 BCE is given by Sheila Adam, in her highly regarded 1966 work [Adam 66] on Greek sculptural technique, and Stewart [Stewart 75] splits the difference, asserting that it first became common at around 370, but that it was known 70 years earlier. The date given by Adam appears to be at least 70 years too late, and indeed, even Blümel's estimate may not be early enough, but all three estimates post date the nominal beginning of the Classical Period in 480 BCE. Like many more modern carvers, Classical Period carvers often overused the drill, and at times, it can become intrusive.
The use of the drill is obvious and unmistakable when it is used to make round holes, but distinguishing slots made with the running drill from slots cut with the aid of the drill can be tricky. However, there are a number of indicators. The first is that the running drill cornered poorly; if a groove has bends, it was probably drilled. Also, the direct marks of both tools took a lot of work to remove completely, so traces of the tools are often visible on the bottom and sides, particularly in deep cuts and in areas that would not be easily seen when the work was installed. Circular traces of the drill often remain on the bottom of slots, as do semi-cylindrical vertical scoops on the sides. The running drill does not leave either kind of trace, because it does not cut from the face. Instead, it was worked back and forth as it rotated, cutting a straight, or gently arcing groove of unwavering breadth, leaving distinctive long, shallow, waves on the bottom, which often terminate with a crease where the linear motion stopped and reversed repeatedly. Unlike the drill, the running drill needed little cleanup on the sides because it cut a slot, rather than a row of cylinders. Therefore, the chisel and rasp marks on the sides of drilled grooves are usually an indication of the use of the drill, even if the cylinders have been entirely obliterated. All of these marks can be very apparent when illuminated from a low angle. Note that the use of one of these tools does not preclude the use of the other. Modern sculptors sometimes use the drill first, and then clean out the webbing with a grinder, which is the modern equivalent of the running drill. There is no reason to suppose that ancient carvers did not do this as well.
On many carvings of the Classical and Hellenistic period, entire areas seem to have been carved primarily with the drill and/or running drill, particularly drapery, where the use can be spotted wherever long parallel folds of drapery are seen. Note the examples shown below detail of a grave stele from Piraeus, Attica, C. early-Fourth Century BCE. On the left we see running drill work that looks almost as if it were done with a router. Note the long slots of unvarying width between folds. A narrow bit has been used to cut the slots between the fingers. Note the long narrow channels of unchanging width. On the right we see relatively crude work with a drill to separate the folds in the the garment. The remains of cylindrical holes are visible particularly at the lower ends, but at the bottom, particularly on the far right. Rough chisel work also remains, which together with the incomplete removal of the webbing between the holes, simulates the bunching and wrinkles of the fabric.
Both of these tools remained common until power tools made them obsolete, and bow-drills are still used by traditional carpenters in remote areas, so it is possible that somewhere, the bow-drill is still used on stone, but both tools are more or less extinct in the developed world.
The cultural context in which sculpture was made changed radically after Greece became an empire. Prior to and throughout the Classical period, sculpture had been primarily for public and religious purposes, but the international trade that flourished in consequence of the Athenian Empire and the subsequent Macedonian Empire founded by Philip II and advanced by Alexander, produced a far more cosmpolitan society, and a class of wealthy people who used architecture and sculpture as a way to display their personal wealth and status, and of course, as objects of beauty in their own right. Simultaneously, Rome was increasingly occupying a similar role in the Western Mediterranean, and developing its own class of wealthy conspicuous consumers.
The Hellenistic Period, which begins with the death of Alexander the Great in 323 BCE, at the peak of his conquests, saw the diffusion of Greek culture across the Mediterranean world and the development of a large and growing market for sculpture throughout the region, a market that would only grow in the centuries that followed.
The Laocoön Group, shown below is an example of the radically freer and more naturalistic styles that developed in this environment. The fluidity of both the overall composition and the surface modeling of Hellenistic sculpture are remarkable when compared to Archaic and even Classical Period work. Work of such complexity is virtually impossible without some degree of mechanical copying, which was increasingly used, both for producing originals from models, and for copying existing masterpieces. Copies of the great Greek works were made in large numbers, and many of the works of the Classical Period, particularly bronze sculpture, are now known only from marble copies done during this period, and subsequently by the Romans, who absorbed the Greek traditions wholesale, adding their own aesthetic spin.
Hellenistic artists abandoned the traditional practice of sculpting from all sides equally, and characteristically worked front-to-back, with the front often approaching completion even as the back remained embedded in the block. All of the basic tools, used in essentially the modern way, are in evidence.
Sculpture continued to be used in public buildings and temples, but a vast new market opened up as well, among the wealthy citizens of the Greek and Roman Mediterranean. These new patrons loved not only figures and compositions from mythology, but for the first time, genre sculpture became popular: images of ordinary people, often not even beautiful people, and of the gods, and minor deities in informal situations.
Even in the Classical Period, the pressures of celebrity were already introducing a degree of distinction between the creative act and the hands-on work of execution. For the first time, sculptors were famous personages. A corollary to the new practice of attaching the sculptor's name to works of art was (and remains) the impossibility of a famous artist who works on a large scale personally executing all of the work demanded of him or her by the public. The pressure to produce was as great for Phydias in the Fifth Century BCE as for Jeff Koons in the 21st Century CE, and this pressure only grew with the cosmpolitan markets of the Hellenistic period.
The evolving market for art in the Hellenistic period further widened the conceptual gap between the creative act and the execution, because well known pieces, both new and old, were routinely copied for shipment for customers who could be anywhere in the Mediterranean world. The commercial production of art made indirect carving indispensable, and indirect carving inherently discounts the resistant nature of the stone, because other people will be doing the hard work. Even bronze sculpture, which almost always originates as clay or wax, was routinely copied into stone, a practice which frankly ignores the nature of stone and directly copies the flexibility of clay.
The separation of the creative act from the labor of the carving makes radically more complex compositions feasible, and inevitably frees the artist to be more ambitious, but at the cost of divorcing the the conception of the work from the properties of the medium. It is for this reason, that the issue has excited intense passion among artists and critics, with partisans of direct carving instinctively regarding indirect carving as a form of aesthetic cheating. The issue transcends logic, and it tends to be a relatively modern concern. There is a romance to stone, about artists doing their own work, and about Greece itself, that strongly colors even scholarly discussions of the subject.
Yet the Greeks themselves were not romantic about stone the way we are. It was bronze, not marble, was the more24 celebrated sculptural medium in Classical Greece, and the painters of sculpture were as famous as the sculptors--the carving was only one part of a finished piece. We know Greek stone carving better than Greek bronze, primarily because the high intrinsic value of bronze insured that the bronzes would be melted down the first time the metal was needed more for weapons than for decoration25. While it is impossible to fully understand the aesthetics of artists from an ancient culture, it would be surprising if master modelers, accustomed to the quintessentially indirect process of bronze casting, who routinely painted marble, and decorated it with jewelery, weapons, and hair cast in bronze, when placed in charge of teams of stone carvers, would share the modern disdain for indirect carving.
After the Hellenistic Period, with one possible exception, the stone sculptor's tool kit evolved only incrementally until the early 20th Century, when electric and pneumatic power tools, ultra-hard metals, new abrasives, saws that could cut stone as easily as wood, and numerous other technologies, began to be introduced. The possible exception to this multi-milliennium technological stability is the group of advanced tools and techniques developed during the Renaissance for transferring three dimensional designs from a preliminary plaster model to stone. Evidence for the use of true pointing frames(see Chapter Indirect Carving) and the triple calipers in Ancient Greece is ambiguous, although they are known to have used fixed reference points on the works in progress.