The conservation and restoration of Ancient Greek pottery is a sub-section of the broader topic of conservation and restoration of ceramic objects. Ancient Greek pottery is one of the most commonly found types of artifacts from the ancient Greek world. The information learned from vase paintings forms the foundation of modern knowledge of ancient Greek art and culture. Most ancient Greek pottery is terracotta, a type of earthenware ceramic, dating from the 11th century BCE through the 1st century CE. The objects are usually excavated from archaeological sites in broken pieces, or shards, and then reassembled. Some have been discovered intact in tombs. Professional conservator-restorers, often in collaboration with curators and conservation scientists, undertake the conservation-restoration of ancient Greek pottery.
Conservation and restoration of ceramic objects is a process dedicated to the preservation and protection of objects of historical and personal value made from ceramic. Typically this activity of conservation-restoration is undertaken by a conservator-restorer, especially when dealing with an object of cultural heritage. Ceramics are created from a production of coatings of inorganic, nonmetallic materials using heating and cooling to create a glaze. Typically the coatings are permanent and sustainable for utilitarian and decorative purposes. The cleaning, handling, storage, and in general treatment of ceramics is consistent with that of glass because they are made of similar oxygen-rich components, such as silicates. In conservation ceramics are broken down into three groups: unfired clay, earthenware or terracotta, and stoneware and porcelain.
Terracotta, terra cotta or terra-cotta, a type of earthenware, is a clay-based unglazed or glazed ceramic, where the fired body is porous. Terracotta is the term normally used for sculpture made in earthenware, and also for various practical uses including vessels, water and waste water pipes, roofing tiles, bricks, and surface embellishment in building construction. The term is also used to refer to the natural brownish orange color of most terracotta, which varies considerably.
A ceramic is a solid material comprising an inorganic compound of metal, non-metal or metalloid atoms primarily held in ionic and covalent bonds. Common examples are earthenware, porcelain, and brick.
Ancient repairs were made to damaged pottery using metal pins or staples, which could be made of copper, lead, or bronze.Animal or vegetable based adhesives may have also been used. Fragments from other vessels were sometimes used to replace damaged or missing sections of an object. The decorative elements on the replacement pieces may or may not have matched the rest of the vase.
Restoration methods used during the 18th through early 20th century generally attempted to restore vessels to a near pristine state and hide any evidence of past damage.Archaeological discoveries and a surge in the popularity of ancient Greek art in the 18th and 19th centuries created a high demand for objects and artifacts. The customary restoration method started with reassembling vessel fragments. Missing fragments were replaced with new glazed and fired pieces of pottery and gaps were filled in with plaster. The surface was then painted, sometimes extensively. Materials used included shellac, protein glues, oil paints, gypsum, plaster of Paris, barium sulphate, calcite, clay, kaolin, and waterglass (calcium silicate). In some cases, decorative imagery was censored and painted over, in order to appeal to the tastes of contemporary society and potential collectors.
Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes (pictured) and dissolved in alcohol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish. Shellac functions as a tough natural primer, sanding sealant, tannin-blocker, odour-blocker, stain, and high-gloss varnish. Shellac was once used in electrical applications as it possesses good insulation qualities and it seals out moisture. Phonograph and 78 rpm gramophone records were made of it until they were replaced by vinyl long-playing records from the 1950s onwards.
The modern approach to conservation generally involves using non-destructive methods to evaluate objects and restoration techniques which emphasize the difference between areas of modern repair and ancient craftsmanship. Reversible adhesives, paint, and other materials are used in restorations.Conservation departments at museums such as the Getty Villa approach conservation of ancient pottery with the goal to "visually integrate filled areas and make them less obtrusive while still distinguishing them from the original ceramic and preserving an object's history."
Most ancient Greek pottery is terracotta, a type of earthenware fired clay ceramic. The composition of minerals, metal, organic and other inorganic materials in the clay varies depending on its source. These variations affect the color of the clay before and after firing. Iron is the most common material found in clay, and can add red, grey, or buff coloring to the object.Pottery can be coarse wares, which are undecorated or only minimally decorated utilitarian vessels, or fine wares, which are decorated, finely potted, and used for a variety of purposes, including ceremonial use. Vase paintings were primarily created using slip, a thin, transparent layer of clay which turned color after firing. Other materials used in vase paintings include added pigment, added clay to create a relief on the surface, or dilute gloss that added color after firing. Unevenly applied gloss or misfiring also created variations in color or surface texture. Gilding was also sometimes added after firing.
Ceramics, and ancient ceramics in particular, can suffer a variety of types of damage. Most agents of deterioration are due to environment and are inherent to the materials; however, the most common damage is caused by human action.
Breaks, losses, or abrasions can be caused by improper handling, impact (dropping), or excavation. Ceramics are strong in compression, but weak under tension, meaning they are fragile and susceptible to mechanical shock.
If a piece of pottery has been buried in salty or alkaline soil or submersed in seawater, the clay may have soaked up soluble salts, such as sulphite, nitrates, or chlorides. Changes in relative humidity can cause the salts to react and dissolve (in high humidity) or recrystallize (in low humidity).These reactions can cause pottery to suffer surface losses or delamination.
Previous restorations can cause unintended damage over time. Metal pins or staples can corrode and deteriorate. Plaster repairs may become unstable. In-painting may fade or discolor. Intentional over-painting from past conservation efforts is another form of damage. Scenes were sometimes altered in order to appeal to current tastes. A common example is a fig leaf being painted over a nude figure. Overly aggressive cleaning with acid can also cause damage. Acid cleaning is meant to remove insoluble salts and minerals from the surface of archaeological ceramics. Pottery that has been improperly cleaned and damaged by acid may have pitted, cracked, powdery, or flaking surfaces.
Preventive conservation measures can help slow further deterioration or damage.
As with any fragile ceramic object, proper handling techniques will help prevent accidental damage. Objects should be handled as little as possible. When handling is necessary, objects should be held at their strongest points only. Pressure on the weakest points, such as handles, necks, or areas with existing damage, should be avoided. Objects should be handled with clean, dry hands, or with nitrile gloves. Cotton gloves are not recommended, because the fabric prevents a stable grip and threads can snag on rough surfaces. Objects on display in museums are secured with mounts or protected by cases to prevent unwanted or accidental contact. Vessels may be displayed upright or at an angle, depending on the decorative elements on display. Any mounts should keep the object stable without putting pressure on any fragile areas.
Despite having been dried and fired, pottery clay is still a porous material which will react to changes in environmental conditions. Avoiding extreme changes in temperature can help maintain the condition of ancient Greek pottery. As discussed above in the section on damage from Soluble Salts, preventing extreme fluctuations in relative humidity can also help prevent further deterioration. Objects should be protected from water and dirt.
The following techniques are used by conservators to evaluate the condition of ancient Greek pottery and determine appropriate treatment. Examination is the first step in the conservation process.
Conservators begin the evaluation of an object with careful visual inspection to identify areas of weakness, loss, delamination, discoloration, or old repairs. Further examination with a low power microscope can help conservators identify materials and technical features, such as pigment, gilding, or added clay.
When exposed to invisible UV light, many types of materials will display certain colors of visible light. This can enable conservators to identify areas of different media throughout the object.
X-rays can reveal breaks, internal features, or hidden ancient repairs, such as pins.Another type of X-ray, called X-ray fluorescence (XRF) spectroscopy can reveal the elemental and chemical composition of a material. X-ray absorption near edge structure (XANES) spectroscopy can reveal the iron oxidation states in pottery (the factor that determines black and red color) and X-ray absorption fine structure (EXAFS) analyses can provide information on the molecular structure of iron minerals.
After evaluation is completed, conservator-restorers can determine the most appropriate form of treatment. Treatments can range from non-invasive techniques, such as cleaning, to more invasive conservation, such as disassembly, reconstruction, and restoration.
Basic mechanical cleaning can remove dirt, dust, and grime. Cleaning solvents and water can also be used to remove dirt, varnish, wax, in-painting, or adhesives. Acids should be used with caution. Desalination is a cleaning method that removes as much soluble salt from the porous fired clay as possible. Fragments are soaked in highly purified water for multiple days. The water is changed regularly until salt levels are reduced.
For vessels that have been previously conserved and reassembled, shards may need to be disassembled in order to remove old restoration materials and complete conservation. Adhesives and fill are systematically removed, revealing the original pottery and allowing the vessel to be deconstructed.
Separated shards are carefully reassembled. Conservators use identifying clues, such as shape, texture, and decorative pattern or painted scenes, to piece together fragments. Missing shards can be recreated out of plaster and replaced. In-painting is used to disguise areas of repair. In modern conservation treatment, the media used by conservators is reversible and can be distinguished easily from ancient material. Different conservators, or conservation departments, may have different policies regarding in-painting. Some conservators leave replacement fragments completely undecorated in order to easily distinguish them as modern additions. Some conservators paint silhouettes of missing figures, using existing fragments, scene narrative, and other extant vases as examples. This approach helps show the narrative of the painted scene, while still distinguishing the modern restoration from the original fragments. Some conservators use more extensive in-painting to recreate missing decoration.
The Affecter Amphora, in the collection of the Walters Art Gallery in Baltimore, Maryland, is a case study for the history of conservation of Greek vases. The black figured Attic (meaning from Athens region) vessel was created around 540 BCE by a well documented vase painter known as the Affecter Painter. Treatment of the vase in the 1980s provided the conservation field with significant insight into the history of the restoration of Greek vases. Conservators discovered that the amphora had been broken and repaired in antiquity. Samples of burial dirt found within holes in the vase proved that the repairs were made prior to the vase being used in an ancient funeral. Conservators also discovered that the vase was restored in the late 19th century with materials and methods typical of the time period. Plaster, replacement pieces of terracotta, and extensive overpainting had been used in the restoration. Overpainting disguised repairs and also altered the appearance of nude satyrs on the decorative panels. The 1980s conservation revealed the original work of the Affecter Painter and restored the vase to a stable condition.
The Francois Vase, in the collection of the National Archaeological Museum in Florence, Italy, is a large Attic volute krater, which is both a superb example of black-figure pottery from c. 570-560 BCE, as well as an example of extensive conservation work. The vase was discovered in a tomb in 1844. In the year 1900, a member of the museum staff smashed the display case and the vase shattered into over 600 pieces. It was restored by 1902, and then restored again in 1973, with previously missing pieces.
Conservation and Restoration of Ceramic Objects
Pottery of Ancient Greece
Earthenware is glazed or unglazed nonvitreous pottery that has normally been fired below 1200 °C. Porcelain, bone china, and stoneware, all fired at high enough temperatures to vitrify, are the main other important types of pottery.
A vase is an open container. It can be made from a number of materials, such as ceramics, glass, non-rusting metals, such as aluminium, brass, bronze, or stainless steel. Even wood has been used to make vases, either by using tree species that naturally resist rot, such as teak, or by applying a protective coating to conventional wood. Vases are often decorated, and they are often used to hold cut flowers. Vases come in different sizes to support whatever flower its holding or keeping in place.
Ancient Greek pottery, due to its relative durability, comprises a large part of the archaeological record of ancient Greece, and since there is so much of it, it has exerted a disproportionately large influence on our understanding of Greek society. The shards of pots discarded or buried in the 1st millennium BC are still the best guide available to understand the customary life and mind of the ancient Greeks. There were several vessels produced locally for everyday and kitchen use, yet finer pottery from regions such as Attica was imported by other civilizations throughout the Mediterranean, such as the Etruscans in Italy. There were various specific regional varieties, such as the South Italian ancient Greek pottery.
A conservator-restorer is a professional responsible for the preservation of artistic and cultural artifacts, also known as cultural heritage. Conservators possess the expertise to preserve cultural heritage in a way that retains the integrity of the object, building or site, including its historical significance, context and aesthetic or visual aspects. This kind of preservation is done by analyzing and assessing the condition of cultural property, understanding processes and evidence of deterioration, planning collections care or site management strategies that prevent damage, carrying out conservation treatments, and conducting research. A conservator's job is to ensure that the objects in a museum's collection are kept in the best possible condition, as well as to serve the museum's mission to bring art before the public.
Kintsugi(金継ぎ, "golden joinery"), also known as Kintsukuroi(金繕い, "golden repair"), is the Japanese art of repairing broken pottery by mending the areas of breakage with lacquer dusted or mixed with powdered gold, silver, or platinum, a method similar to the maki-e technique. As a philosophy, it treats breakage and repair as part of the history of an object, rather than something to disguise.
Stained glass conservation refers to the protection and preservation of historic stained glass for present and future generations. It involves any and all actions devoted to the prevention, mitigation, or reversal of the processes of deterioration that affect such glass works and subsequently inhibit individuals' ability to access and appreciate them, as part of the world's collective cultural heritage. It functions as a part of the larger practices of cultural heritage conservation (conservation-restoration) and architectural conservation.
Conservation and restoration of objects made of glass is one aspect of conservation and restoration of cultural heritage. The nature and varying composition of the material, and the variety of types of object made from it, demand certain specialized techniques. The conservator needs to be aware of "agents of deterioration" presenting particular risk to glass objects, and how to prevent or counteract their effects. Relevant education and training is available in certain countries through museums, conservation institutes and universities.
A paintings conservator is an individual responsible for protecting cultural heritage in the form of painted works of art. These individuals are most often under the employ of museums, conservation centers, or other cultural institutions. They oversee the physical care of collections, and are trained in chemistry and practical application of techniques for repairing and restoring paintings.
The conservation and restoration of outdoor artworks is the activity dedicated to the preservation and protection of artworks that are exhibited or permanently installed outside. These works may be made of wood, stone, ceramic material, plastic, bronze, copper, or any other number of materials and may or may not be painted. When applied to cultural heritage this activity is generally undertaken by a conservator-restorer.
A conservation scientist is a museum professional who works in the field of conservation science and whose focus is on the research of cultural heritage through scientific inquiry. Conservation scientists conduct applied scientific research and techniques to determine the material, chemical, and technical aspects of cultural heritage. The technical information conservation scientists gather is then used by conservator and curators to decide the most suitable conservation treatments for the examined object and/or adds to our knowledge about the object by providing answers about the material composition, fabrication, authenticity, and previous restoration treatments.
Conservation and restoration of objects made from plastics is an activity dedicated to the conservation of objects of historical and personal value made from plastics. When applied to cultural heritage this activity is generally undertaken by a conservator-restorer. Within museum collections there are a variety of artworks and artifacts that are composed of plastic material whether they are synthetic or semi-synthetic; these were created for a range of uses from artistic, to technical, to domestic use. Plastics have become an integral component of life and many plastic objects have become staple icons or objects worth preserving for the future. Although relatively new material for museum collections, plastics having originated in the 19th century, they are deteriorating at an alarming rate, risking the loss not only of the objects themselves, but through their deterioration processes they place objects within their vicinity at risk too. Plastics are made of synthetic, semi-synthetic and organic material, all of which are susceptible to degradation, with their respective off-gassing being harmful to the objects nearby in museum collections.
The conservation and restoration of shipwreck artifacts is the process of caring for cultural heritage that has been part of a shipwreck. Oftentimes these cultural artifacts have been underwater for a great length of time. Without conservation, most artifacts would perish and important historical data would be lost. In archaeological terms, it is usually the responsibility of an archaeologist and conservator to ensure that material recovered from a shipwreck is properly cared for. The conservation phase is often time-consuming and expensive, which is one of the most important considerations when planning and implementing any action involving the recovery of artifacts from a shipwreck.
Ceramic art is art made from ceramic materials, including clay. It may take forms including artistic pottery, including tableware, tiles, figurines and other sculpture. Ceramic art is one of the arts, particularly the visual arts. Of these, it is one of the plastic arts. While some ceramics are considered fine art, as pottery or sculpture, some are considered to be decorative, industrial or applied art objects. Ceramics may also be considered artefacts in archaeology. Ceramic art can be made by one person or by a group of people. In a pottery or ceramic factory, a group of people design, manufacture and decorate the art ware. Products from a pottery are sometimes referred to as "art pottery". In a one-person pottery studio, ceramists or potters produce studio pottery.
The conservation and restoration of painting frames is the process through which picture frames are preserved. Frame conservation and restoration includes general cleaning of the frame, as well as in depth processes such as replacing damaged ornamentation, gilding, and toning.
The conservation and restoration of lacquerware prevents and mitigates deterioration or damage to objects made with lacquer. The two main types of lacquer are Asian, made with sap from the Urushi tree, and European, made with a variety of shellac and natural resins. Lacquer can be damaged by age, light, water, temperature, or damaged substrate.
The conservation and restoration of paintings is carried out by professional painting conservators. Paintings cover a wide range of various mediums, materials, and their supports. Painting types include fine art to decorative and functional objects spanning from acrylics, frescoes, and oil paint on various surfaces, egg tempera on panels and canvas, lacquer painting, water color and more. Knowing the materials of any given painting and its support allows for the proper restoration and conservation practices. All components of a painting will react to its environment differently, and impact the artwork as a whole. These material components along with collections care will determine the longevity of a painting. The first steps to conservation and restoration is preventive conservation followed by active restoration with the artist's intent in mind.
Nigel Reuben Rook Williams was an English conservator and expert on the restoration of ceramics and glass. From 1961 until his death he worked at the British Museum, where he became the Chief Conservator of Ceramics and Glass in 1983. There his work included the successful restorations of the Sutton Hoo helmet and the Portland Vase.
The Modern and Contemporary Art Research Initiative is a program started by the Getty Conservation Institute (GCI). It began in 2007 in response to the variety of new materials and technologies being used by contemporary artists in their work, and the lack of known conservation treatments for these new materials. This area was seen as a gap in the field of conservation, but also posed unique challenges when considering the intention of the artist and the physical aging that his or her materials might endure. According to Thomas F. Reese, "Conservators...must enter into the critical spirit of the works themselves if they are to save and transmit not merely decontextualized fragments but their essence to the future."
The conservation and restoration of wooden artifacts refers to the preservation of art and artifacts made of wood. Conservation and restoration in regards to cultural heritage is completed by a conservator-restorer.