Condition Report Terms Explained: Craquelure, Foxing and Inpainting

How an artwork condition report is organised

An artwork condition report is written in a specialist shorthand. Conservators, registrars and specialists share a vocabulary that lets them record what they see precisely, but that precision can leave a collector unsure whether a phrase describes a normal sign of age or a problem that needs attention. This guide explains the terms that appear most often in a fine art condition report and what each one usually implies.

Most reports follow a similar order. They describe the support first (the canvas, panel, paper or other material carrying the image), then the ground and paint layers, then any varnish or surface coating, and finally the frame or mount. The front and back are often called the recto and verso. Locations are usually given from the viewer's position, as in 'upper left' or 'lower right edge', and some reports use a grid or clock positions for greater precision.

Two words shape how every other term should be read: stable and active. A stable condition has probably been present for a long time and is not changing. An active condition, such as paint that is still lifting, is ongoing and may need a conservator's attention. The same term can be minor in one report and urgent in another depending on which of these applies.

Paint and surface terms: craquelure, cupping, flaking and abrasion

The paint layer attracts the most vocabulary, because it is where change is easiest to see and where the image itself lives. Of the terms below, active flaking and lifting are the conditions most likely to need prompt professional attention. Craquelure, stable old losses and a discoloured varnish are common in older works and usually call for considered treatment decisions rather than urgency.

Support terms often appear alongside them. Planar distortion describes a canvas or panel that is no longer flat, stretcher marks are lines or cracks that follow the wooden bars behind a canvas, and a draw is a local ripple radiating from a corner or a fixing point.

Works on paper: foxing, cockling and light damage

Paper has its own vocabulary, largely because it responds quickly to moisture, light and the materials it touches.

Foxing describes small reddish-brown spots scattered across a sheet. Its causes are still debated, with mould activity and metallic impurities in the paper both implicated, and it is generally associated with damp conditions. A paper conservator can often reduce foxing, but the storage conditions that encouraged it matter as much as the treatment.

Cockling is a wavy or rippled distortion of the sheet, usually caused by an uneven response to humidity or by a mount that restricts the paper's movement. Mat burn, or mat toning, is a brownish line or band where an acidic mat has been in contact with the paper for years. A tide line is a pale or brown edge left by water that has spread through the sheet and dried.

Light damage appears as fading of colours or media, and as yellowing or darkening of the paper itself. Reports sometimes compare the exposed image area with the margins protected by the mat, where the original tone may survive. Because light damage is cumulative and irreversible, a note of fading is also a note about how the work should be displayed in future.

Treatment terms: inpainting, retouching, overpaint and relining

Many terms record what has been done to a work rather than what has happened to it. They are not faults, but a buyer or insurer will want to know about them, and their extent affects how a work is understood.

Inpainting is a conservator's application of paint confined strictly to areas of loss, so that the original surface is not covered. Retouching is often used as a near synonym, although some writers use it more broadly. Overpaint is the term to watch: it means paint applied over original paint rather than only within losses, and it is frequently found in older restorations where damage was disguised rather than compensated. Fills are the putty-like material placed in a loss before it is inpainted.

Lining means attaching a new fabric to the back of an original canvas to support it, historically with glue-paste or wax-resin adhesives. Relining strictly means removing an old lining and applying a new one, although the two words are often used interchangeably. A strip lining reinforces only the edges. Consolidation is the process of re-adhering flaking or lifting paint. For panels, cradling refers to a wooden lattice attached to the back, a historical practice that can itself cause cracking.

A good report distinguishes old interventions from recent ones where it can, and says whether treatment was documented. A conservator's treatment report, if one exists, is the most reliable record of what was done.

Examination terms: UV fluorescence and raking light

Some terms describe how the work was examined rather than its condition. They tell a reader how much confidence to place in the findings.

Examination under ultraviolet light is standard in many fine art condition reports. Under UV, many aged natural varnishes fluoresce with a milky or greenish glow, while retouching applied on top of that varnish often appears as darker patches. A report may note retouching visible under UV along an edge or in a particular area. The method has limits: restoration beneath a later varnish may not show at all, some modern materials fluoresce in unexpected ways, and a clean UV result does not prove the absence of restoration.

Raking light is light directed across the surface from a low angle. It exaggerates texture and shows planar distortion, cupping, lifting and old repairs to the canvas. Transmitted light, shone through a sheet of paper or a canvas from behind, reveals thin areas, tears and losses. If a report mentions none of these methods, it was probably a visual examination in ordinary light, which is useful but less thorough.

Questions to ask about a condition report

A report is only useful if its reader understands it. When a term is unclear or its significance is not stated, the author should be asked, and a competent examiner will expect the question.

The most useful questions are about change and consequence. Is the condition stable or active? Does it affect how the work can be displayed, handled or shipped? Is treatment advisable, and if so, how urgent is it? For a work being bought, it is also reasonable to ask whether the report's author has any connection to the seller.

Reports also become more useful over time. Keeping each one in the work's condition file, with its photographs and the date of examination, allows later reports to be compared line by line. Craquelure that has not changed across several reports is reassuring; a new area of cupping is information worth acting on.