Aging is a process by which an

art Art is a diverse range of cultural activity centered around ''works'' utilizing creative or imaginative talents, which are expected to evoke a worthwhile experience, generally through an expression of emotional power, conceptual ideas, tec ...

work, typically a

painting Painting is a Visual arts, visual art, which is characterized by the practice of applying paint, pigment, color or other medium to a solid surface (called "matrix" or "Support (art), support"). The medium is commonly applied to the base with ...

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

, is made to appear old. It is meant to emulate the natural deterioration that can occur over many decades or centuries. Although there may be "innocent" reasons for it, ageing is a technique very often used in

art forgery Art forgery is the creation and sale of works of art which are intentionally falsely credited to other, usually more famous artists. Art forgery can be extremely lucrative, but modern dating and analysis techniques have made the identification of ...

. Paintings deteriorate over time because they are created using essentially incompatible materials, with each having a different reaction to the changes in the environment, including light, temperature and

relative humidity Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation (meteorology), precipitation, dew, or fog t ...

. An oil painting consists of several layers, comprising the base

canvas Canvas is an extremely durable Plain weave, plain-woven Cloth, fabric used for making sails, tents, Tent#Marquees and larger tents, marquees, backpacks, Shelter (building), shelters, as a Support (art), support for oil painting and for other ite ...

, a layer of

gesso A restored gesso panel representing St. Martin of Tours, from St. Michael and All Angels Church, Lyndhurst, Hampshire Gesso (; 'chalk', from the , from ), also known as "glue gesso" or "Italian gesso", is a white paint mixture used to coat rigi ...

base coat, several layers of the

oil-based paint Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. Oil paint also has practical advantages over other paints, mainly because it is waterproof. The earliest surviving ex ...

and then several coats of

varnish Varnish is a clear Transparency (optics), transparent hard protective coating or film. It is not to be confused with wood stain. It usually has a yellowish shade due to the manufacturing process and materials used, but it may also be pigmente ...

to protect the paint surface. With many different materials, it is understandable that each layer may dry at different rates and will also absorb and release moisture at different rates. When this occurs, expansion and contraction of the painting will result in a crazing of the varnish surface. This pattern of small cracks is known as

craquelure Craquelure (; ) is a fine pattern of dense cracking formed on the surface of materials. It can be a result of drying, shock, aging, intentional patterning, or a combination of all four. The term is most often used to refer to tempera or oil pain ...

. Along with the darkening or yellowing of the varnish surface, it is this visual representation of the cracking that is typically the primary indicator of ageing. The purpose for artificially ageing is to create a finished product that accurately reflects an era or is consistent with the environment (usually period) into which it is to be placed.

References

See also