B – Glossary terms

Backing removal:

Objects are often reinforced by adding a backing such as paper or textiles. Backings can become structurally, chemically or aesthetically deleterious to the object, in which case conservators will remove the backing. There are a number of methods that can be used to remove a backing, depending on the material make up of the object and the backing.


Misshapen with fold or kink in material, out of alignment, often referring to projecting elements such as feathers. There may or may not be a break at the bend.

Blanched (Paper):

The opaque, whitish appearance of paint or varnish caused by the leaching out of certain substance or by the pulverization of paint or varnish under pressure as in a scrape or scratch. In either case minute interruptions within the varnish or medium refract light producing a milky appearance. Moisture often causes blanching.


Often caused by the sun or chemicals, this can cause damage to objects, but can also be used to improve the appearance of paper.


The separation of pigments, especially dyes, into adjacent areas.


A convex deformation of the surface, hollow underneath. This can be observed in bulging paint for example.

Bloom (ceramics, glass, metals and stone):

Areas of a white cloudiness to the surface caused by a refraction of light from presence of small cracks/ surface damage/ or powdery deposit.

Bloom (Organics):

Bluish white cloudiness often on a painted or varnished surface, caused by moisture penetrating the surface.


A separation between areas of a hard material such as glass, ceramic, wood, stone and other materials, usually caused by a sudden shock and often occurring at weak points. May also be used to describe damage to brittle paper or cardboard, where pieces have been snapped off.


Loss of strength and flexibility, causing the material to break when bent. Paper is said to be brittle when a corner will not withstand two complete folds without breaking. Plastics also become brittle, through the loss of plasticizing agents.


The object, or element of object, is in more than one piece.

Broken stitching threads / bindings (Organics):

E.g. splits in seams, or broken threads used to secure parts or decorative elements, such as beads.


Of veneered or inlaid surfaces – Material has expanded in size but is fixed in position, so excess bulges or lifts up.


Surface damage caused by fire or heat. Burned surfaces are usually black or brown in colour, friable and brittle. There may also be soot and smoke damage, water damage and melting or softening. This term may also be used to describe damage caused by sunlight or chemical pollutants such as light or mat burn.