At the beginning of the 6thC in Ravenna, Italy about 140 miles south of Venice, the rule of Roman emperor and Ostrogoth King Theodoric the Great ushered in a cultural revival in the visual arts. Classical Roman and new Christian imagery began to merge into Romanesque architecture, innovations in mosaics and illuminated manuscripts such as the “Codex Argenteus” or “Silver Bible.”
A sumptuous book of Bishop Ulfilas’ translations of the gospels into Gothic language was made as a gift of high esteem for King Theodoric. Considered among the first illuminated manuscripts, the “Silver Bible” was scripted with calligraphy penned in gold and silver inks on purple parchment. The text would have been incredibly beautiful and easier to read at vespers.
Codex Agentus, Italy, early 6th century
Illuminated manuscripts were religious texts, usually written in Greek, the language of the Eastern Roman (Byzantine) Empire. Only a precious few manuscripts were made on purple parchment due to the cost of materials and labor. The dying process relied on how parchment was dipped through a sequence of dye baths. The most prized and expensive purple dyestuff was Tyrian purple, a dye substance found in mucous secretions from several species of Mediterranean rock snails. Production of Tyrian purple was controlled by the seaside Phoenician empire and sold as a premium product. As a valuable art material, painters would have used Tyrian purple, very sparingly, as a top coat color.
Orchil samples, Isabella Whitworth, Devon, South West England
The dye orchil, processed from European lichen, was more commonly used. A range of colors from fuscha to deep red was produced after soaking dried orchil in a mixture of ammonia and water (ratio 1:2). Perhaps the technology to process lichen into dye arrived with Goths from Scandinavia where orchil (pronounced: or kil) is commonly found and Goths were described as wearing red cloaks.
Another source of deep red and violet colors was Chrozophora tinctoria, a color bearing plant which grew through the Mediterranean region and N. Africa.
Considering how easy it was to prepare, folium dye was most popular. When stirred into cold water, the seed pods turned the water blue. The dyed water was then soaked into cloth squares which were dried. Upon demand, the clothlets were added into solution until the dye dissolved out of the cloth into the solution. Dyes dissolve in solution and pigments do not.
Chrozophora Tinctoria
The dye was commonly called turnsole, dyer’s litmus or “folium” (pl. folio) from the Latin word for a sheet of parchment folded once to form two leaves which determined the largest size a book could be. C. Tinctoria was used in antiquity until the 19thC invention of ultramarine blue pigment (complex sodium silicate containing sulfur and aluminum).
Folium colors range from deep red to violet so folium was among the dyes used to make purple parchment. Making the correct royal color required expensive expertise because multiple dye colors had to be applied in a specific order to develop the color. Folium dyes also changed colour depending on the acidity or alkalinity of the solution. Whole parchment sheets would have been repeatedly dipped into dye vats of varying colors of folium, orchil and rosy reds from brazilwood pulp. Each color enriched the royal color without making a thicker surface. While parchment was much more resistant to water, fire and the rages of time, parchment tended to buckle when wet so it was attached to a frame out of direct sunlight to dry.
When properly prepared, scribes could write on both sides. Parchment could also be folded and pages stitched together at the fold to create folios for compact and portable codex style books. The change in writing surface proved advantageous for scribes because parchment was more flexible and more opaque than papyrus. When flat and dry, parchment was a strong, flexible support for illumination and illustrated manuscripts until about the 12thC.
Tanner creating parchment from Mendel manuscript dated back to 1425
Creating Parchment
To prepare parchment, raw hides were soaked in vats of lime water mixed into the waste water and mash from beer making. Keeping mixtures warm in limestone troughs sped up both processes perhaps by using the ancient hot stone method. For at least a few days, hides had to be stirred into the brew repeatedly with long poles to keep them from bunching or folding. The lime bath dissolved the epidermal layer to so pelts were easier to scrape smooth.
After rinsing, pelts were gently stretch on to a frame so both sides were left open to the air while the parchment dried. Using sharp, semi-circular (lunar) knifes, both sides were scraped. During the drying process, plaster pigments including calcium carbonate (marble dust, chalk), and lime were rubbed into the flesh side of wet pelt. The collagen in the connective tissue glued pigments into the lime-cured surface to make it stiffer. Pouncing with pumice reduced absorbency by hardening the surface.
Ancient Illuminators also worked slowly in layers. To unify the surface, they applied a thin “staunchgrain” coating made from lime powder, wheat paste and albumen (powdered egg whites) mixed with milk for a gesso layer. A scribe wrote letters designed for gold and silver gilding on a slightly thicker gesso mixed with warm rabbit skin glue. Gesso would have been custom formulated for each job from mixtures of glues and gums to improve the adhesion between thin gold sheets on parchment. For gilding with gold sheets, “bole” was often added to the ground. Bole, made from very finely ground red clay pigments with a deep red color was used to obscure fine lines between misaligned gold sheet. Then no light fine lines showed through to mar the sheen.
Gilding and Glair
For gilding, calligraphers brushed glair over letters drawn in black ink. “Glair” was an easily available fixative made from egg whites with or without water. Egg whites were whipped into frothy stiff peaks and left to settle. After 24 hours, a skim layer formed and below was glair liquid. Once poured into a clean container, the fixative was stored for a few months before using. Longer storage was said to increase adhesion but the smell of old glair made it commonly called “La putrido.”
Folio – Blue Quran Brooklyn Museum
About 20 minutes after applying glair, artisans used their warm moist breath to humidify the glair surface to increase adhesion before they quickly set a gold leaf sheet in place using a small brush or cotton wad. The gold and silver letters and patterns were burnished with special tools, often made from agates set into handles. Depending on temperature and ambient humidity, surface was left to dry and excess gold or silver particles were brushed off.
Old High German Psalter by Notker the German
Books were, in general, scribed in black inks, originally made from a mixture of soot, water, hide glue and/or plant gum. Using soot for carbon black ink was industrialized by the Egyptians about 4000 years ago. Soot is produced by incomplete oxidation of organic matter burned in kilns; or, closer to home, by scrapping soot off a glass lamp shade. “Lamp black” was collected after lamp oil was burned too close to the wick. Collecting soot, a by-product of plaster pigment production and ceramics manufacturing must have been a terrible job.
Some kilns were designed with soot traps which directed particles away from the main heat source to collect and cool. Because soot did not have a uniform particles size, soot had to be further processed. Small fine black-blue particles were reserved for manuscript illustrators and calligraphers; also for the notaries for royals and the elites. A product of combustion, carbon black ink retained its color overtime but rubbed off easily and letters were erased. Specialty inks would have been modified with additives like gums to speed drying and glues to increase adhesion.
Making Gall Ink
Making iron gall ink was easier than any process that begins by harvesting soot. To make gall ink, an extract of gall nuts (oak apples) was added to a solution of water and gum Arabic plus iron filings. Once reacted, a clear liquid turned black-brown.
Gall ink was ready to use and did not clog pens like carbon ink. However, the indelible alternative gall ink was a notably different shade of black. When used to embed drawings and writing into prepared surfaces, gall ink was very difficult to erase, but its color was not blue-black.
Gall inks faded into an array of clearly visible grey-brown sepia colors made famous during the Renaissance but not blue-black.
Despite ease of use and fixity, Medieval artists and artisans did not include gall ink among their art media until paper was well established in Europe.
In the 12thC the Fabriano paper mill was producing a million sheets a year in Italy. For those with high status and wealth, prayer books were richly illustrated with bright colors by the finest artists working in Europe. Nobility, wealthy merchants and the clergy demonstrated their prosperity by the quality of their libraries rather than murals on the walls.
The Prophets Hosea and Jonah, Raphael, c. 1510