This article will explain what experts look for when determining the condition of works on paper, a category that includes prints, drawings and watercolors on paper, and posters. It will give you the tools to determine if common condition issues are present in the artwork that you own.
Works on paper are notoriously delicate. Keep in mind that if you discover condition issues, they will not necessarily hurt the sales value of your artwork. Some condition issues are inherent to the materials used to create the piece and their presence can help confirm authenticity.
It is best to remove a work on paper from the frame when looking for condition issues because the frame can conceal parts of the work. However, do not remove the piece from the frame unless you are comfortable with this process.
When handling the work, make sure your hands are clean and dry (or wear clean gloves if you have them). This is because over time, the oils from your fingertips can cause damage to the artwork. Do not pick up the work by its corners. Use your thumb and forefinger to gently hold the sheet of paper from two separate points to minimize the chance of creating creases in the paper from handling. Note that certain issues may require a magnifying glass or blacklight to detect. If you use a light source, do not let the light increase the temperature of the paper.
The following are common condition issues:
Water Damage
Look at the front and back of the artwork. Are there any lighter areas with wavy edges that could have resulted from exposure to liquid (water or other)? Has the piece been displayed in a high-humidity environment, such as a bathroom a kitchen?
Tears or Rips
Is the paper torn anywhere? Pay close attention to the edges and corners, and examine the front and back.
Creases
Creases are ridges or grooves in paper produced by folding or pressure against a hard edge or from improper handling or storage.
Bumps
Bumps occur from impact at the edges and corners of a sheet of paper, leaving dents. Bumped corners look "rounded" instead of sharp.
Buckling
Buckling is bending or warping that causes the paper to appear “wavy.”
Mat Burn
Mat burn is an area of discoloration on the print in the area where the mat was touching the paper. This is caused by acid in non-archival framing materials.
Sun Damage and Fading
Has the artwork been displayed or stored in an environment with strong light? This can cause the colors to fade. If a colored area of the artwork was covered by the mat and therefore not exposed to light, compare the colors here to the colors in the rest of the image to determine if they are faded.
Foxing
Foxing is small brownish spots that appear on paper. These usually consist of mold or fungus growth, metallic impurities in the paper, or dampness. Sometimes these spots can be hidden by the image, so look carefully. Look at the front and back side of the paper. If you have a black light available, use it to scan the surface of the work. Foxing will appear yellow under black light.
Soiling or Dirt
Look at the front and back of the paper. Do you see any dirty areas? Does the paper look darker it should be? Are there any fingerprints on the paper?
Repairs
Check the back side of the paper for any patches that indicate repairs of torn paper. To your knowledge, has the work ever been restored? Look for a change in paper thickness or texture, or a vein of thin paper where a tear had been mended. If you have a magnifier, use it to examine the surface. If you have a black light, patches will appear a brighter blue than the original paper and glue from a restoration will appear lighter.
Insects and Mold
Exposure to moisture from humidity can cause mold growth and attract insects. Mold can be identified by raised areas of white, yellow, brown, black, or blue discoloration. Insects can distort the artwork by eating the paper or support, leaving small holes, and soiling the paper with brown or white excretion that can cause permanent discoloration. Some insects, such as silverfish, actually feed on pastel, making the surface appear to be "scraping off."
Frame Damage
Is the frame stable? Are there chips? Has the gilding worn away or flaked off? Frames are decorative and also serve to protect the edges and surface of a painting from damage.