Parchment was used during the Middle Ages from tanned animal skins and tend to suffer the following varieties of damage:

1. Brittleness caused by the weakness of the substrate or support resulting from the inherent acidity of the material.

2. Fragility caused by the weakness of the substrate caused by handling.

3. Splitting caused by a linear break in the substrate caused by a contract of restricted paper or rupture along a worn fold or crease.

4. Tear or rip in the substrate caused by an irregular split.

5. Trimming of the original material caused by cutting the edges of the substrate.

6. Loss of the original perimeter caused by loss inside or outside the substrate. 

7. Hole caused by tacking or pin-pricking the substrate.

Mold Damaged Iron Gall Ink Manuscript

Iron Gall Ink was the primary ink used in Europe during the Middle Ages into the nineteenth-century. It was often homemade and varied in recipes.

1. Principal ingredients are tannins extracted from oak galls, iron sulfate, and water.

2. Different recipes result in various levels of chemical stability. 

3. An excess of sulfuric acid and free iron ions lead to a degradation phenomenon known as ink corrosion.

4. Documents are written using iron gall ink are very vulnerable to moisture and accelerate the degradation process.

Boyatzis,S.C., Velivasaki,G., and Malea, E. (2016). A study of the deterioration of aged parchment marked with laboratory iron gall inks using FTIR-ATR spectroscopy and mirco hot table.Heritage Science 4(13), 1-17. DOI: 10.1186/s40494-016-0083-4

Hansen, E. and Lee, S.N. (2011). The effects of relative humidity on some physical properties of modern vellum: Implications for the optimum relative humidity for the display and storage of parchment. Journal of the American Institute of Conservation. Retrieved from http://cool.conservation-us.org/coolaic/sg/bpg/annual/v10/bp10-09.html

Scott C. Schwartz, (2001). Narcissism in collecting art and antiques. Journal of the American Academy of Psychoanalysis 29(4), 633-647.DOI:10.1521/jaap.29.4.633.21542

Deterioration by harmful environment agents such as light, temperature, relative humidity, pollution, and pests.

Document deterioration can be accelerated by inappropriate use, storage, and display.

Light can cause oxidation, which leads paper to fade or darken from chemical changes in the paper. It can also and dehydrate paper making it brittle. 

Temperature changes in handling can cause a rapid rise in temperature and cause the paper to curl or mold as humidity level changes.

Relative humidity is the greatest threat to parchment from water or damp conditions and mold growth from the inadequate air flow. 

Pollution and dirt particles that circulate through unfiltered ventilation systems can cause discoloration and abrasion.

Pests include insects, rodents, and other pests that cause various types of stains and losses. Infested materials should be isolated at once.