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Conservation Glossary

Conservation Glossary

Conservation lingo a bit rusty? Forgot the difference between preventive and interventive conservation? No problem! 

The Icon Glossary brings you all the common terms and phrases used in conservation that you might come across in dealing with conservators. 

Art and Heritage Glossary

If you're looking for more general terms related to art and heritage, scroll down for the handy glossary below, reproduced with permission from Art & Architecture Thesaurus On Line. (Copyright 2004 The J.Paul Getty Trust.)

Astronomical clock
A clock that displays astronomical phenomena, such as the phases of the moon, or a clock that shows sidereal time.

Mechanical figures or contrivances constructed to move as if by their own power, generally by intricate hidden mechanisms.

Bark cloth
A non-woven textile made by beating the inner bark of certain trees and bushes until it is fine and soft. Bark cloth can be painted, stamped, embroidered, or but and sewn as patchwork although it is relatively fragile, especially when wet. It was once used in almost all of sub-Saharan Africa, being reported as early as the mid-16th century in Liberia; today it is found in Ghana and Nigeria.

Bakelite ™ is the original name for phenol plastic; but now usually covers a range of different types of plastic.

An instrument for measuring atmospheric pressure.

Barrel organ
A mechanical pipe organ operated by a rotary handle, which both works the bellows to supply air, and turns a pinned cylinder which, as it is turned, raises keys which cause the sounding of the appropriate pipes.

Arrangements of beads, often attached to textiles.

Boulle work
Marquetry comprised of brass and tortoise shell, applied to furniture especially in the late 17th and early 18th centuries.

Bracket clock
Small, spring driven or pendulum, wood-cased clock intended to be placed on a bracket on the wall, set on a mantel, or carried from room to room; the brackets were often designed to match the style of clocks; generally from the 17th and 18th centuries.

Cast stone
Concrete with a fine aggregate or mortar which is cast into blocks or small slabs using special moulds so as to resemble natural building stone.

Refers to any of various hard, brittle, heat resistant and corrosion-resistant materials made by shaping and then firing a non-metallic mineral, such as clay, at a high temperature.

Strongly built precision timekeeping device especially designed for use on ships; or extremely accurate wrist or pocket watches.

Zitherlike instrument in the form of a rectangular box with a keyboard set in the long side. Strings, usually two per note, run from hitch pins on the left over a bridge to tuning pins at the right. Brass tangents on the rear portion of each key strike the strings from below to produce sound.

Coade stone
Building material, composed of ceramic similar to stoneware, developed in England around 1769, used primarily for architectural decoration.

A work produced by the technique of making compositions in two dimensions or very low relief by gluing paper, fabrics, photographs or other materials onto a flat surface.

Cultural Heritage
Cultural heritage is the things both natural and manmade that are valued for their meaning and significance.

Pottery with a porous body, fired below 1200 degrees Centigrade. It is not vitrified, and must be glazed to render it nonporous.

A usually opaque, vitreous coating, composed chiefly of quartz, feldspar, clay, soda, and borax, applied by fusion to surfaces especially of metal, ceramic or glass; has a glossy appearance on hardening.

Encaustic tile
A technique of decorating clay [tiles] in which the body material is inlaid with clay of another colour.

Items manufactured for a specific, limited use, and usually intended to be discarded thereafter; often printed.

Ethnographic material
Material originating in any culture still living or known through relatively recent history when that material is the concern of ethnographic or ethnological study.

Glass which is drawn into fibrous form and can be woven into cloth. It is strong, light, non-flammable and has a high tensile strength.

Painting by the technique of fresco painting, which is a mural painting technique in which permanent pigments, dispersed in water, are painted on freshly laid lime plaster.

Ordered collection of preserved plants.

Image produced in the Eastern Rite churches, since the 6th century, according to prescribed formulas of subject (Christ, the Virgin, saints, and the great feasts) and composition, for devotional use in the church or home. Most commonly tempera on panel, but may be in any two-dimensional or relief medium, including fresco.

Inlay work
Applied decoration whereby pieces of a material are inserted into similar-sized openings in a surrounding material so as to create a design.

Hard, fine-grained rock composed either of jadeite or nephrite and usually having a colour ranging from dark green to green-white; it takes a high polish and has long been used for jewellery and ornamental objects.

The hard-finish lacquering technique which utilises many coats of varnish composed of shellac dissolved in spirit, then polished and decorated, usually Oriental in style and subject matter. Originally developed as a substitute for genuine Oriental lacquer which was popular during the second half of the 17th century.

Lacquer work
Objects, usually made of thin wood, which are coated and decorated with layers of lacquer, often accompanied by inlays of other substances such as mother of pearl and metal.

Magnetic media
Media capable of storing information in the form of electromagnetic signals such as magnetic tapes or disks.

A technique in which small pieces of wood or other materials are overlaid or inlaid onto another wood surface to form a decorative veneer.

Flexible, transparent sheets (or roll) of film bearing a number of microimages.

Refers to a painting on a very small scale. The term is often applied specifically to small scenes in illuminated manuscripts or to portraits on vellum or ivory that were popular in Europe and America from the Renaissance into the 19th century.

Monument, megalithic
Refers to prehistoric or very ancient monuments built of unusually large stones that have been only very roughly worked or left as found.

Multimedia work
Contemporary works of art that employ several distinct art forms, such as sculpture and music or painting and light art.

Refers to a decoration in any medium that dominates a wall (or ceiling) surface; most often refers to works executed on the wall, but may also refer to works done separately and affixed to the wall.

Non-ferrous metal
Metal that does not have iron as its major ingredient.

Oriental lacquer
Natural resinous exudation, obtained from certain trees found in the Far East.

Brass of bronze which is gilded or is gold in colour.

Painting (tempera)
Tempera refers to a paint formed of an emulsion of fatty and water constituents.

Papier mache
Pulverised paper made into a water paste with an adhesive binder.

A writing material prepared from thin strips of the pith of the papyrus plant laid together, soaked, pressed and dried.

Pietra dura
Inlaid work in which pieces of hard, polished stone are set into marble or another hard surface.

Polychrome sculpture
Sculpture decorated or painted in several colours.

A type of ceramic ware made of a refracting white clay, or ‘kaolin’, and a feldspathic rock, that react when fired so the clay serves to hold the shape of the object and the rock fuses into a natural glass. In China, it includes any such ware that is highly fired enough to produce a ringing sound when struck. In Europe, it is limited to hard-fired ceramic ware that is translucent.

Preventive Conservation and Preventive Conservator
Preventive conservation encompasses all interventions made by a conservator on cultural heritage , other than remedial conservation. The purpose of these interventions is to maintain, and where possible enhance, the condition of cultural heritage by the sustainable management of the risks posed by the agents of deterioration, to facilitate people’s access to and enjoyment of this heritage, taking account of the interests of both present and future generations, whilst preserving the significance it had for past generations.

Preventive conservators may work as generalists in collections care, organising, implementing, advising on and providing training in routine environmental management and general collections care including documentation, storage, display and routine cleaning (housekeeping). Others may specialise in specific areas of preventive conservation, such as particular classes of material or types of collection (for example archives), of environmental agents (such as relative humidity, temperature, light, insect pests), aspects of collections care (such as packing and storage for building works and other events such as filming), management of collections conservation projects and collections (such as the organisation of surveys, prioritisation and commissioning of remedial conservation, exhibition and display), and developing emergency procedures. Specialists will have sufficient knowledge of the range of materials affected by their work to form a proficient level of understanding of the impact of their professional practice.

Remedial conservators are also proficient in their knowledge and application of the preventive conservation measures that affect their area of practice, but may not have the breadth or depth of experience of the range of preventive conservation measures required to describe preventive conservation as their principle area of practice.

A clock of great accuracy containing a deadbeat escapement and temperature compensated pendulum used for the regulation of other timepieces; usually tall case clocks in form.

Refers to wall or furniture surfaces made by mixing fine plaster of powdered selenite (gypsum) with alum, glue, water, and pigment to create an effect that imitates marble or pietra dura.

Can be used to describe a variety of processed animal hides or skins, though generally of a ray fish. Distinguished either by the rough, granular texture on the grain side of the leather or a similar pattern; frequently dyed green.

A type of light, malleable plaster made from dehydrated lime (calcium carbonate) mixed with powdered marble and glue and sometimes reinforced with hair. It sets more slowly that plaster and so is suitable for crafting sculpture and architectural decoration, external and internal. Differs from most other plasters which are made with calcium sulphate, rather than the calcium carbonate used in stucco, and set much more quickly.

The technique of preparing lifelike representations of animals by stuffing the skin or moulding it around a model of the specimen.

Trompe l’oeil
French term meaning “deceive the eye”, applied to images so realistic that they may fool the viewer into thinking that the represented objects, scenes, textures or points of view are real rather than images. The term is generally used to refer to Western art, generally to two-dimensional art or bas-relief. It was seen in ancient Greek art, refined by the ancient Romans, and was popular in the Renaissance and later in Europe and America. Effects include painted textures of wood or marble on walls or columns, realistic portrayals of views framed by painted faux windows, false frames from which the contents of a still life or portrait appear to extend into the viewer’s space, and depictions of shelves or cupboards with various articles seen through half-open doors. In the late 20th century, the exteriors of entire buildings have been painted in trompe l’oeil.

Lacquer made from the sap of the tree Rhus vernicifluca or other trees of the Anacardiaciae family, used in Japanese and, to a lesser extent, Chinese lacquering and also in Japanese prints called “urushi-e”. The term is sometimes used to refer to objects made from this lacquer and the technique of doing the lacquering.

Typically refers to a thin layer of material, often wood or plastic but sometimes a precious material such as ivory, bonded to and used to cover a usually inferior material.

Verre eglomise
The technique of decorating glass in which a painted, drawn or gilded image is executed on the underside of the glass and backed with metal foil, usually gold or silver.


Image: Book damaged by bookworm; CC BY-SA 4.0