Mat Burn

Our Aproach to a Mat Burn on Prints and Drawings

Mat burn is a common problem in artworks that were framed with low-quality, acidic mats. Once the old mat is removed, conservators evaluate whether the brown staining can be reduced or stabilized. The approach is always careful and tailored to the specific artwork, because not all papers or media can undergo the same treatments.

1. Removing the Source of the Problem
The first step is to remove the acidic mat and any backing materials that may be contributing to ongoing deterioration. This immediately stops further acid migration into the artwork.

2. Surface Cleaning
Conservators gently clean the surface of the paper to remove dust, grime, and loose impurities that might interfere with later treatments. This step is done with soft tools such as eraser crumbs, cosmetic sponges, or brushes.

3. Aqueous Treatment (When Safe)
When the paper and media can safely tolerate moisture, conservators may wash the artwork in carefully controlled baths. Washing can neutralize acids and lift some discoloration from the paper fibers.
This step must be done by experts: not all papers or inks can be washed, and some may bleed, weaken, or deform.

4. Local Stain Reduction
For mat burn specifically, conservators sometimes use local bleaching, poultices, or suction-table techniques to reduce the intensity of the dark line without over-treating the rest of the sheet.
These treatments are very precise and often applied only to the affected area.

5. Rehousing in Archival Materials
After treatment, the artwork is re-mounted using museum-quality, acid-free materials so new mat burn will not form. This step is essential for long-term preservation.

Stabilization Rather Than Complete Erasure

Mat burn cannot always be fully removed. In many cases, the goal is to lighten the stain so it is less visually distracting while ensuring that the paper is stable for the future. Many works affected by mat burn contain fragile media such as:

• watercolor
• charcoal, chalk, pastel
• iron gall ink
• early printing inks
• gouache
• unstable pigments

These materials can bleed, fade, dissolve, or shift when exposed to moisture, chemicals, or strong light.
A treatment strong enough to remove the last trace of mat burn could damage the artwork’s original media—which is never acceptable.

Stabilization means reducing the stain only to the point that the artwork remains safe.

Ethical conservation prioritizes safety over perfection

The cornerstone of conservation ethics is minimum intervention. If a treatment required to fully erase mat burn could cause damage, conservators opt for reversible treatments, gentle lightening, non-destructive stabilization, and preventive strategies such as improved housingThe goal is not to make the artwork look new, but to make it as stable, safe, and aesthetically legible as possible.