Collector’s Guide: Art Conservation & Paper Artworks

Collector’s Guide: Art Conservation & Paper Artworks

Whether you want to conserve water painting or if you are looking for an art conservation/ paper conservators/ art restorers for your work, you must know about the following terms to be able to identify the conditions and protect your work.

At APRE Art House, each work is inspected and thoroughly checked before display and sale. A condition report is made by our team of experts and is accompanied with each work.

A painting of a landscape with greenish brown spots on it.
Foxing: Image Courtesy: Port Douglas Framer

The Historical Significance of Paper

Paper has been the foundation for artistic expression for centuries. With its origins dating back to 200 BCE in China, this versatile medium has become a staple for artists across the world. As a collector or conservator, comprehending the nuances of paper conservation is crucial to maintain the integrity and value of artworks.

Defining "Work on Paper"

A "Work on Paper" encompasses a broad array of art forms, including drawings, watercolors, and prints. These are typically made by applying materials like paint, charcoal, and graphite onto thin sheets derived from organic fibers such as those from trees or grass. The delicate nature of paper makes it susceptible to wear and aging, necessitating vigilant care, storage, and occasional conservation efforts.

Common Paper Conditions and Issues:


In common terms it's called Fungus on paper. It is characterized by reddish-brown spots, foxing is a common sign of aging in paper, often exacerbated by humidity and climate change. These spots can stem from iron content or mildew spores within the paper. Prevention involves maintaining a cool, dry, and clean environment, shielded from direct light to mitigate these blemishes.

The term possibly originates from the reddish-brown color akin to a fox or from the presence of ferric oxide, a rust compound. Affected paper is described as being 'foxed.'

Interestingly, foxing is uncommon in very early printed works, known as incunabula, which date before 1501.

As for remedies, foxed documents can be treated using various methods. These include chemical treatments with sodium borohydride, selected bleaches(less than 5%), distilled water,diluted hydrogen peroxide, or even laser technology. A professional Conservator would be the person to decide the treatment and exercise it.

Cockling or Warping

This refers to an uneven paper surface or a ripple effect, generally the result of humidity. Proper environmental control is key to preventing such deformation.

Cockling conditions on paper are created in the dryer section as the sheet shrinks under unrestricted drying conditions.

Treatment methods for cockling in paper may involve controlled humidification, heat, or pressure to smooth out the surface. Managing cockling in paper and other materials involves maintaining stable relative humidity levels to preserve their condition.


Improper handling or storage can lead to grooves in the paper surface, known as creasing. Proper handling techniques and storage conditions can minimize this risk.

Tears, Rips & Holes

Paper's fragility means it can easily tear or rip without careful handling, and holes might be caused by insect activity.


Discoloration can occur due to two main factors: acidity and oxidation. Acidity is prevalent in papers produced between 1850 and 1950, while oxidation leads to yellowing, triggered by light exposure.

Many elements contribute to the discoloration of paper, with water damage or high humidity levels being among the most prevalent issues.

When paper comes into contact with water, it creates an environment conducive to the development of acid and mold. Other contributors to discoloration include smoke, sunlight, and various environmental factors that can accelerate these damaging conditions.

Once acidification and mold growth start on a piece of art, they tend to spread erratically across the artwork. The progression of this damage is unpredictable, not necessarily following a linear path, but rather jumping sporadically from one section to another, eventually affecting the entire artwork if left unchecked.

Two artwork images. one is yellowed and the other one looks fresh.
Discoloration: Image courtesy: Fine art restoration

Acidic Burn

Acids present in wood and wood-based products can cause significant browning. This is often seen in discoloration around the edges, where acidic mats or tapes have been used in framing.

UV Damage

All paper is light-sensitive, with prolonged exposure leading to discoloration and brittleness, particularly in low-quality papers like newsprint.


Dust, fingerprints, smoke, and even breath can leave grime on paper, potentially dulling colors and soiling the surface. Regular dusting with a soft brush and professional framing can help protect against grime.

Insect Damage

Insect excretions and rust from paper clips can cause lasting damage. These issues are complex and often require professional conservation intervention for proper removal and preservation.


Photographs benefit from individual enclosures to prevent damage. Acid-free paper or suitable plastics like polyester, polypropylene, and polyethylene are recommended for storage, avoiding PVC due to its damaging effects.

Optimal Storage Practices for Paper Items

Preservation of paper is greatly enhanced by proper storage, which includes:


Maintaining a cool (at or below room temperature), moderately dry (around 35%-40% relative humidity), clean, and stable environment. This means avoiding places like attics or basements where there is a higher risk of environmental instability and leaks.


Protecting items from forms of light, particularly direct or intense sources. Minimize exposure to direct sunlight and consider UV protective glass for framing.


Positioning items away from heat sources such as radiators and air vents.


  • Employing supportive enclosures such as acid-free and lignin-free folders, mats, and archival boxes, which come in alkaline buffered or neutral pH options. These materials can neutralize acids present in aging paper, although caution should be taken as some media on paper may react to alkaline environments.
  • Storing oversized papers either flat, unrolled, or rolled in appropriate conditions.
  • Isolating acidic papers to prevent the spread of acidity to other works.
  • Using polyester film sleeves that provide sufficient support and visibility but avoiding materials that can generate static electricity, which can damage powdery media like pastel or charcoal.
  • Use archival quality paper clips to prevent rust and related damage.

Final Thoughts


Trimmed papers lose their margins and deckled edges, which are essential for the paper's character and value.


While oils may be retouched by a restorer, watercolors and other delicate mediums are not as forgiving once faded.

Final Thoughts on Conservation

Works on paper are intricate and diverse. The unifying advice from experts is to cherish what you love and take care of it, consulting a qualified paper conservator when necessary.

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