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53-574: The Medici lions are a pair of marble sculptures of lions : one of which is Roman , dating to the 2nd century AD, and the other a 16th-century pendant . By 1598 both were placed at the Villa Medici , Rome . Since 1789 they have been displayed at the Loggia dei Lanzi in Florence . The sculptures depict standing male lions with a sphere or ball under one paw, looking to the side. Copies of

106-476: A recommended exposure limit (REL) of 10 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. Dust, debris and temperature fluctuations from working marble can endanger the eye health of employees. For the staff involved in marble processing, it is necessary to provide eye protection equipment, and it is recommended to improve the education of all workers on occupational health risks and strengthen preventive measures. As

159-552: A 13-foot zinc-alloy robotic arm located in Carrara , Italy, mill marble slabs to fit designs created by artists from the United States, Great Britain, and elsewhere. Artists often blend robotic carving with hand carving. The process begins with digital files artists create to guide their robotic carving systems. “The data drives computer-controlled, stone-carving machines that use diamond and carbide bits that slowly mill away

212-570: A growth of 12% annually for the 2000–2006 period, compared to 10.5% annually for the 2000–2005 period. The largest dimension marble application is tile. The stone and marble industry is one of the largest industries in Palestine, contributing 20-25% of its total industrial revenues, generating USD $ 400–$ 450 million in revenue annually. The industry employs 15,000–20,000 workers across the West Bank across 1200–1700 facilities, and amounts to 4.5% of

265-438: A large amount of waste not being land-filled, reducing environmental pollution, thereby realizing the sustainability of marble. Converting waste to generate economic income and restore degraded soil can improve the environment. The nature of marble is soft and porous, so it is easily stained by colored liquids and scratches easily. Maintenance and cleaning is particularly important. Marble sculpture Marble has been

318-583: A potential hazard. Mitigations such as dust filters, or dust suppression are suggested, but more research needs to be carried out on the efficacy of safety measures. In the United States, the Occupational Safety and Health Administration (OSHA) has set the legal limit ( permissible exposure limit ) for marble exposure in the workplace as 15 mg/m total exposure and 5 mg/m respiratory exposure over an 8-hour workday. The National Institute for Occupational Safety and Health (NIOSH) has set

371-401: A rough version of the sculpture,” described New York sculptor Barry X Ball in a 2020 interview. “Then, we take it from there.” Ball's sculpture Sleeping Hermaphrodite required 10,000 hours of hand-sculpting after the initial robot sculpting phase was completed. While some artists and scholars criticize the use of robot technology in marble sculpture, others see it as a natural evolution of

424-406: A shallower stroke at this point in the process. Eventually, the sculptor has changed the stone from a rough block into the general shape of the finished statue. Tools called rasps and rifflers are then used to enhance the shape into its final form. A rasp is a flat, steel tool with a coarse surface. The sculptor uses broad, sweeping strokes to remove excess stone as small chips or dust. A riffler

477-425: A typical process using magnesium fluorosilicate (MgSiF 6 ) and hydrochloric acid (HCl) taking place. The resulting calcium hexafluorosilicate (CaSiF 6 ) is bonded to the surface of the marble. This is harder, more glossy and stain resistant compared to the original surface. The other often used method of finishing marble is to polish with oxalic acid (H 2 C 2 O 4 ), an organic acid. The resulting reaction

530-504: Is a metamorphic rock derived from limestone, composed mostly of calcite (a crystalline form of calcium carbonate , CaCO 3 ). The original source of the parent limestone is the seabed deposition of calcium carbonate in the form of microscopic animal skeletons or similar materials. Marble is formed when the limestone is transformed by heat and pressure after being overlain by other materials. The finest marbles for sculpture have no or few stains, though natural stains can be incorporated into

583-405: Is a long, hefty piece of steel with a point at one end and a broad striking surface at the other. A pitching tool may also be used at this early stage, which is a wedge-shaped chisel with a broad, flat edge. The pitching tool is useful for splitting the stone and removing large, unwanted chunks. The sculptor may also use a mallet , which is similar to a hammer with a broad, barrel-shaped head. When

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636-399: Is a rock composed of calcium and magnesium carbonate , mostly white and pink. Common marble varieties are granular limestone or dolomite . The hardness of marble is very high, because the internal structure of the rock is very uniform after long-term natural aging, and the internal stress disappears, so the marble will not be deformed due to temperature, and has strong wear resistance. It

689-413: Is a smaller variation of the rasp, which can be used to create details such as folds of clothing or locks of hair. Polishing is the last step of the carving process. Sculptors use a variety of fine, abrasive materials such as sandpaper or emery paper to highlight patterns in the stone and to accentuate its natural sheen. Some sculptors may also use tin oxide to achieve a high-lustre polish. Regardless of

742-439: Is a very popular building material. The following table is a summary of the features of Marble. White marble has been prized for its use in sculptures since classical times . This preference has to do with its softness, which made it easier to carve, relative isotropy and homogeneity, and a relative resistance to shattering. Also, the low index of refraction of calcite allows light to penetrate 12.7 to 38 millimeters into

795-538: Is as follows: In this case the calcium oxalate (CaC 2 O 4 ) formed in the reaction is washed away with the slurry, leaving a surface that has not been chemically changed. The haloalkaliphilic methylotrophic bacterium Methylophaga murata was isolated from deteriorating marble in the Kremlin . Bacterial and fungal degradation was detected in four samples of marble from Milan Cathedral ; black Cladosporium attacked dried acrylic resin using melanin. Marble

848-470: Is commonly used for sculpture and as a building material . The word "marble" derives from the Ancient Greek μάρμαρον ( mármaron ), from μάρμαρος ( mármaros ), "crystalline rock, shining stone", perhaps from the verb μαρμαίρω ( marmaírō ), "to flash, sparkle, gleam"; R. S. P. Beekes has suggested that a " Pre-Greek origin is probable". This stem is also the ancestor of

901-412: Is described in the legend of Pygmalion , and even earlier, the ancient Greek sculptors used it from c.  650 BC . It consists of holding the pointed chisel against the stone and swinging the hammer at it as hard as possible. When the hammer connects with the striking end of the chisel, its energy is transferred down the length and concentrates on a single point on the surface of the block, breaking

954-414: Is far more difficult to work and much less suitable for refined works. Compared to metals such as bronze , furthermore, marble is inflexible and vulnerable to fracturing. This drawback means that sculptors must incorporate specific supporting features into the sculpture to prevent collapse. In Thomas Ridgeway Gould's The West Wind, for example, he poised the figure's short and slender ankles delicately upon

1007-615: The Venus de Milo and many other Ancient Greek sculptures , and Pentelic marble , from near Athens , used for most of the Parthenon sculptures , and by the Romans. Carrara marble from northern Italy was used by the Romans, and very extensively up to recent decades, when the pure white statuario grade more or less ran out. This was used by Michelangelo and other Renaissance sculptors, and later exported, including to America. Marble

1060-574: The English word "marmoreal", meaning "marble-like." While the English term "marble" resembles the French marbre , most other European languages (with words like "marmoreal") more closely resemble the original Ancient Greek. Marble is a rock resulting from metamorphism of sedimentary carbonate rocks , most commonly limestone or dolomite . Metamorphism causes variable re-crystallization of

1113-493: The dimension stone trade, the term marble is used for any crystalline calcitic rock (and some non-calcitic rocks) useful as building stone. For example, Tennessee marble is really a dense granular fossiliferous gray to pink to maroon Ordovician limestone, that geologists call the Holston Formation . Ashgabat , the capital city of Turkmenistan , was recorded in the 2013 Guinness Book of Records as having

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1166-425: The many different types of marble the pure white ones are generally used for sculpture, with coloured ones preferred for many architectural and decorative uses. The degree of hardness is right to carve without too much difficulty, but still give a very durable result, if not exposed to acid rain or seawater . Famous individual types and quarries include from classical times Parian marble from Paros , used for

1219-579: The Medici lions are on display in the garden of the Corleone family estate in The Godfather (1972). 43°46′9.13″N 11°15′20.37″E  /  43.7692028°N 11.2556583°E  / 43.7692028; 11.2556583 Marble In geology , the term marble refers to metamorphosed limestone , but its use in stonemasonry more broadly encompasses unmetamorphosed limestone. Marble

1272-620: The Medici lions have been made and publicly installed in over 30 other locations, and smaller versions made in a variety of media; Medici lion has become the term for the type. A similar Roman lion sculpture, of the 1st century AD, is known as the Albani lion , and is now in the Louvre . Here, the stone used for the ball is different from the basalt body. Both may derive from a Hellenistic original. A pair of lions were required by Ferdinando I de' Medici, Grand Duke of Tuscany , who had acquired

1325-524: The Villa Medici in 1576, to serve as majestic ornaments for the villa's garden staircase, the Loggia dei leoni. The first lion originates from a 2nd-century marble that was first mentioned in 1594, by the sculptor Flaminio Vacca , by which time it was already in the collection of Ferdinando; Vacca reported that it had been found in the via Prenestina , outside Porta San Lorenzo . According to Vacca,

1378-419: The balls of her small feet. This would not be possible without the deliberate decision by Gould to distribute almost all of the marble's weight to her massive, flowing skirt. Unlike bronze sculpture, this statue is not hollow; her drapery is one solid block of marble. Sculptors usually begin by knocking off, or "pitching," large portions of unwanted stone. A suitable tool for this task is a point chisel , which

1431-487: The excavated material will be waste, this is often then used as chips for flooring or wall finish, and uses for which high-calcium limestone is suitable. Marble sludge waste can be used as a mineral filler in water-based paints. Using ground calcium carbonate as a filler in paint production can improve the brightness, hiding power and application performance of paint, and can also replace expensive pigments such as titanium dioxide . Recycling of marble waste leads to

1484-454: The favorite medium for Greek and Roman sculptors and architects (see classical sculpture ), marble has become a cultural symbol of tradition and refined taste. Its extremely varied and colorful patterns make it a favorite decorative material. Places named after the stone include Marblehead, Massachusetts ; Marblehead, Ohio ; Marble Arch , London; the Sea of Marmara ; India's Marble Rocks ; and

1537-429: The finished marble ages, it becomes harder and more durable. Preference to the cheaper and less translucent limestone is based largely on the fineness of marble's grain, which enables the sculptor to render minute detail in a manner not always possible with limestone. In contrast to limestone, marble is also extremely weather-resistant. As a result, surface changes due to the immediate environment are not always visible to

1590-437: The formation of "black-crust" (accumulation of calcium sulphate, nitrates and carbon particles). Vinegar and other acidic solutions should be avoided in the cleaning of marble products. Crystallization refers to a method of imparting a glossy, more durable finish on to a marble floor (CaCO 3 ). It involves polishing the surface with an acidic solution and a steel wool pad on a flooring machine. The chemical reaction below shows

1643-566: The limestone. Green coloration is often due to serpentine resulting from originally magnesium-rich limestone or dolomite with silica impurities. These various impurities have been mobilized and recrystallized by the intense pressure and heat of the metamorphism. Acids react with the calcium carbonate in marble, producing carbonic acid (which decomposes quickly to CO 2 and H 2 O) and other soluble salts : Outdoor marble statues, gravestones , or other marble structures are damaged by acid rain whether by carbonation , sulfation or

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1696-414: The lion had been a relief, which was carved free of its background and reworked by "Giovanni Sciarano" or Giovanni di Scherano Fancelli , of whom little is now known. The second was made and signed by Vacca, also in marble, as a pendant to the ancient sculpture at a date variously reported as between 1594 and 1598 or between 1570 and 1590. The pair were in place at the Loggia dei Leoni in 1598 The pendant

1749-437: The mallet connects to the tool, energy is transferred through the tool, shattering the stone. Most sculptors work rhythmically, turning the tool with each blow so that the stone is removed quickly and evenly. This is the "roughing out" stage of the sculpting process. While a mallet provides the force needed to fracture the marble, it must be used accurately. The smallest miscalculation can ruin the intended sculpture and even injure

1802-428: The method, however, a glossy marble sculpture will appear more translucent than one that has not been polished. The Italian terms for the basic carving tools of stone sculpture are given here, and where possible the English terms have been included. In addition to those hand tools listed above, the marble sculptor uses a variety of hammers – both for the striking of edge tools (chisels and hand drills) and for striking

1855-433: The naked eye. This feature can pose challenges when dating ancient works. Marble sculptors must be careful when handling their materials, as the stone can absorb skin oils and develop yellow or brown stains. While more resistant than limestone it is subject to attack by weak acids, and so performs poorly in outdoor environments subject to acid rain . For severe environments, granite is a more lasting material but one which

1908-546: The nation's GDP. The vast majority of the industry's exports are to Israel. Marble in the geologic sense does not naturally outcrop in Palestine, and that the vast majority of commercially labeled marble produced in Palestine produced would be geologically considered limestone. Particulate air pollution exposure has been found to be elevated in the marble production industry. Exposure to the dust produced by cutting marble could impair lung function or cause lung disease in workers, such as silicosis . Skin and eye problems are also

1961-645: The original carbonate mineral grains. The resulting marble rock is typically composed of an interlocking mosaic of carbonate crystals . Primary sedimentary textures and structures of the original carbonate rock ( protolith ) have typically been modified or destroyed. Pure white marble is the result of metamorphism of a very pure ( silicate -poor) limestone or dolomite protolith. The characteristic swirls and veins of many colored marble varieties, sometimes called striations , are usually due to various mineral impurities such as clay , silt , sand , iron oxides , or chert which were originally present as grains or layers in

2014-446: The point deeper into the stone and remove more material at a time. Some stoneworkers also spin the subbia in their fingers between hammer blows, thus applying with each blow a different part of the point to the stone. This helps prevent the point from breaking. Some contemporary sculptors use advanced robots and automation software to help them create carved works in marble. A 2021 New York Times article describes how robots like ABB2,

2067-413: The preferred material for stone monumental sculpture since ancient times, with several advantages over its more common geological "parent" limestone , in particular the ability to absorb light a small distance into the surface before refracting it in subsurface scattering . This gives an attractive soft appearance which is especially good for representing human skin, and which can also be polished. Of

2120-411: The sculptor uses other tools to refine the figure. A toothed chisel or claw chisel has multiple gouging surfaces which create parallel lines in the stone. These tools are generally used to add texture to the figure. An artist might mark out specific lines by using calipers to measure an area of stone to be addressed and marking the removal area with pencil, charcoal or chalk. The stone carver generally uses

2173-489: The sculptor. Some artists prefer to carve directly onto the stone, without a model; the Renaissance artist Michelangelo , for example, claimed that his job was to free the human form trapped inside the block. Other artists sculpt a preliminary model out of clay or wax and then translate its features to stone through the use of calipers or a pointing machine . Once the general shape of the statue has been determined,

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2226-409: The stone before being scattered out, resulting in the characteristic waxy look which brings a lifelike luster to marble sculptures of any kind, which is why many sculptors preferred and still prefer marble for sculpting the human form. Construction marble is a stone which is composed of calcite, dolomite or serpentine that is capable of taking a polish. More generally in construction , specifically

2279-587: The stone directly (Bocciarda a Martello in Italian, Boucharde in French, Bush Hammer in English). Following the work of the hammer and chisel, the sculptor will sometimes refine the form further through the use of rasps, files and abrasive rubbing stones and/or sandpaper to smooth the surface contours of the form. Hammer and point work is the technique used in working stone, in use at least since Roman times, as it

2332-413: The stone. This is continued in a line following the desired contour. It may sound simple but many months are required to attain competency. A good stone worker can maintain a rhythm of relatively longer blows (about one per second), swinging the hammer in a wider arc, lifting the chisel between blows to flick out any chips that remain in the way, and repositioning it for the next blow. This way, one can drive

2385-623: The towns of Marble, Minnesota ; Marble, Colorado ; Marble Falls, Texas , and Marble Hill, Manhattan, New York . The Elgin Marbles are marble sculptures from the Parthenon in Athens that are on display in the British Museum . Total world quarrying production in 2019 was approximately 316 million tonnes; however, quarrying waste accounted for 53% of this total production. In the process of marble mining and processing, around half or

2438-631: The villa in 1803. These copies were made by the French sculptor Augustin Pajou . The original Medici lions (1598) have since 1789 stood in the Loggia dei Lanzi , Piazza della Signoria , Florence . There is a smaller bronze left-looking sculpture attributed to Italian sculptor Pietro da Barga and the same period. Later copies or replicas include (ordered by first year): Versions in Saint Petersburg , Russia include: Versions in southern Russia and later Ukraine include: Downsized copies of

2491-655: The widespread exchange of marble objects, including building elements, sculptures, and sarcophagi . There was a significant increase in the distribution of white marble from the late 1st century BC to the end of the 2nd century AD. A gradual decline in distribution started in the third century AD. According to the United States Geological Survey , U.S. domestic marble production in 2006 was 46,400 tons valued at about $ 18.1 million, compared to 72,300 tons valued at $ 18.9 million in 2005. Crushed marble production (for aggregate and industrial uses) in 2006

2544-457: The work itself. Among the commonly available stones, only marble has a slight translucency i.e. subsurface scattering that is comparable to that of human skin . It is this translucency that gives a marble sculpture a visual depth beyond its surface and this evokes a certain realism when used for figurative works. Some types of marble also have the advantage that, when first quarried, it is relatively soft and easy to work, refine, and polish. As

2597-415: The world's highest concentration of white marble buildings. The extraction of marble is performed by quarrying . Blocks are favoured for most purposes, and can be created through various techniques, including drilling and blasting, water jet and wedge methods. Limestones are often commercially and historically referred to as marble, which differs from the geological definition. In 1998, marble production

2650-753: Was China with a 64% market share, followed by India with 11% and Italy with 5%. White marbles throughout the Mediterranean basin were widely utilized during the Roman period. Extraction centers were unevenly distributed across the Italian Peninsula , mainland Greece , the Aegean Islands , Asia Minor , and smaller hubs like those in the Iberian Peninsula . The need for extensive trade arose due to this imbalance, leading to

2703-465: Was 11.8 million tons valued at $ 116 million, of which 6.5 million tons was finely ground calcium carbonate and the rest was construction aggregate . For comparison, 2005 crushed marble production was 7.76 million tons valued at $ 58.7 million, of which 4.8 million tons was finely ground calcium carbonate and the rest was construction aggregate. U.S. dimension marble demand is about 1.3 million tons. The DSAN World Demand for (finished) Marble Index has shown

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2756-447: Was dominated by 4 countries that accounted for almost half of world production of marble and decorative stone. Italy and China were the world leaders, each representing 16% of world production, while Spain and India produced 9% and 8%, respectively. In 2018 Turkey was the world leader in marble export, with 42% share in global marble trade, followed by Italy with 18% and Greece with 10%. The largest importer of marble in 2018

2809-633: Was made from a capital that had come from the Temple of Jupiter Optimus Maximus . The Villa Medici was inherited by the house of Lorraine in 1737, and in 1787 the lions were moved to Florence , and since 1789 they flank the steps to the Loggia dei Lanzi at the Piazza della Signoria . The sculptures were replaced by copies at the Villa Medici when Napoleon relocated the French Academy in Rome to

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