[2] One of the best ways to become familiar with the variety of issues caused by various materials is to learn about how such manuscripts were made in the past and how they were subsequently treated in later years.
Pigments add another layer to the problem, forcing a preservationist to fit environmental conditions to two different (and possibly conflicting) sets of ideal limits.
Nonetheless, the very embellishments that allowed these books to survive are the reason that today's conservators find illuminated manuscripts more challenging to maintain than their plain counterparts.
This is important not just to conservators, but to the historians who rely on them to trace the economic trends and artistic evolution in a time that is commonly referred to as the Dark Ages, or more properly known as the Migration Period (476–800 C.E.).
Illuminated manuscripts are some of the hardest books to conserve, but every effort must be made to preserve them not only for their own beauty and value but for their historical significance as some of the only surviving written records of an era.
With the advent and propagation of Christianity in medieval Europe, illustrated books rapidly became a way to convey religious teachings in a time when most of the population was illiterate.
Later, histories and chronicles became more popular, coinciding with the gradual spread of knowledge and the founding of universities throughout Europe in the latter part of the Middle Ages (Anderson 13).
Without the illuminated manuscripts historians have to study today, much of this information about the gradual return of wealth and learning in the Migration Period would be difficult or even impossible to accurately trace and date.
Illustrating religious texts allowed people to see the stories that church leaders read to them, and to create a personal connection outside of the oral tradition.
This also served to demonstrate their fidelity to and strengthen their ties with the church, whose support and influence with the common people played a major part in keeping the upper class in power.
Because all but the very smallest of local churches had at least a plain copy of the bible, the range from completely unadorned manuscripts to the lavish and intricate designs embellished with rich gold leaf seen in the more famous versions of the art are clearly represented.
While this influence is also represented in buildings and other archeological evidence such as coinage and works of art, the prevalence of illuminated manuscripts from different areas and time periods provides a sort of historical litmus test to the prosperity of the region.
Once the format of a rectangular codex protected by hard or stiff covers had become a commonly known alternative to the scroll form previously used, it rapidly gained popularity for its durability and versatile applications.
Gradually the intricate designs of tooled covers and decorated pages evolved to appeal to wealthy clients, and the books became an art form in and of themselves.
For both illuminated and unadorned books, these loose bindings cause problems for conservators when they have not been properly and firmly bound after the writing and decorating was completed.
For example, if a lavish cover was inlayed with lapis lazuli, if would be possible to infer that the bindery was able to source materials from as far east as Afghanistan (Alexander 40).
As for the paper most people would recognize today, the first true example was created in China around 105 A.D. using beaten, strained, and dried vegetable fibers such as tree bark.
However, this paper was very expensive and generally had to be imported at the time that illuminated manuscripts were being widely made, so it appears less often than the third alternative, parchment (Permanence/Durability of the Book 11).
It is worth noting that those manuscripts with paper pages are much harder to conserve, and the acids present in the plant fibers naturally cause it to yellow and break down over time.
Not only does it mold quickly in high humidity environments, but early forms of ink that were commonly used on papyrus could simply be washed off without leaving a trace.
Any book bearing this color would have been especially costly, and helps to map the economic structure of Migration Period Europe through the supply chain used to create it and the person wealthy enough to afford it.
Some scribes also wrote or made small drawings in the margins of the books, often providing historians with a window into the life on the average man in the Migration Period.
However, it was far less common for books and papers to be embellished with precious metals, and this aspect of illuminated manuscripts adds another facet of difficulty for conservators that is not found elsewhere.
While this is an issue for conservators, in rare cases a glue can be traced to a specific bindery, thus placing the book in its correct area and context, making it far more useful to historians.
While modern conservators have ways of limiting this though control of humidity, older books have often seen their illumination corrode to the point that to attempt to clean it would simply remove the metal entirely.
Likewise, inspecting the drawings and inscriptions in the margins provides a unique historical window, but a careless historian might touch the page and damage fragile and flaking paint.
While a few famous examples claim the spotlight in major institutions, small museums, libraries, and religious centers put their own, smaller treasures on display to the public without the expertise of a conservator to aid them.
Their illumination, adhesives, paints, inks, papers, and even their very bindings can pose issues ranging from toxic chemicals to lost pages.
This fact is all the more important when you look past the aesthetic and monetary value of these books and realize that they are some of the only surviving written pieces from a time when there is so little historical information available that textbooks call it the Dark Ages.
In the future, as technology evolves, it may be possible to gradually bring the economy and social system of the Migration Period into the light by carefully analyzing these books.