Craqueleren

Craqueleren is the appearance of a network of fine cracks on a surface, most often seen in paintings and ceramic glazes. In Dutch usage the verb craqueleren describes the process of developing craquelure or the resulting pattern. In paintings, craquelure forms as the surface layers age and shrink at different rates: drying oil or tempera contracts differently from the ground, binders oxidize and varnishes become brittle, producing a mosaic of small fissures. The pattern can be fine and dense (closed craquelure) or more open and irregular (open craquelure). Craquelure can reveal information about a work’s materials and techniques and is commonly used as an indicator of age and provenance, though it is not a definitive dating marker.

In ceramics and glazed pottery, glaze crackling occurs during cooling from firing or under later thermal or mechanical stress, yielding a network of cracks that may be accentuated by staining or by the glaze’s misfit with the body. Craquelure can be intentional, created by designers to imitate the appearance of age or to achieve a decorative effect.

Causes across contexts include environmental fluctuations in humidity and temperature, mechanical vibrations, aging of binding media, and differential shrinkage between layers or glaze and body. In conservation practice, craquelure is usually preserved as part of the object's or painting’s history; stabilization aims to prevent enlarging cracks and to avoid irreversible alteration, while treatments should respect original materials and aesthetics.