Environmental humidity can induce irreversible deformation of manuscript supports (expansion, contraction, bending), threatening long-term preservation. Using a controlled-variable design, we exposed Tibetan paper, palm leaf, and birch bark supports to five constant relative humidities (30.0 %, 55.3 %, 76.2 %, 86.0 %, and 95.0 %) and monitored moisture content, dimensional change, and deformation for 145 days. Structural and compositional differences were considered to compare underlying deformation mechanisms. Deformation in all supports increased significantly with humidity, and the magnitude, rate, and patterns matched their hygroscopic/desorption behaviour. Palm leaves showed the largest expansion–contraction, followed by birch bark, while Tibetan paper exhibited the best dimensional and planar stability. Palm-leaf deformation is attributed to highly hygroscopic constituents, a loose microstructure and oriented vascular bundles. Birch-bark lateral curling is governed by structural anisotropy and contrasting hydrophilicity between inner and outer surfaces. Tibetan paper remains stable due to its dense fibre network and traditional manufacturing. Based on the results, ca. 55 % RH is identified as an optimal general storage humidity for all three supports, where projection and expansion ratios fall within relatively stable ranges. These findings establish a unified humidity benchmark for mixed-support collections and support targeted preservation strategies.
Copper ions accelerate the degradation of organic materials; therefore, their identification in historic paper objects is essential for assessing damage risks and support conservation decision-making. In this study, three different test strips for copper ion detection were evaluated: the commercially available Cuprotesmo test, a laboratory-prepared test following Hulthe’s method and a test strip prepared by Han Neevel. The copper tests were evaluated on model papers, historical papers, and solutions containing various metal salts. With the highest limit of detection of 0.22 ± 0.05 % copper, Cuprotesmo is less suitable for determinations in historical papers, as this is comparable to typical copper levels in iron gall inks. Additionally, the test causes pronounced staining on both model and historical materials. Neevel’s tests showed lower limit of detection (0.06 ± 0.04 %) when freshly prepared but produced false-positive responses in the presence of other metal ions, limiting their suitability for routine use. Tests prepared according to Hulthe’s method demonstrated comparable sensitivity to Neevel’s test without ion interference and caused minimal discolouration. Despite a subtle colour change and the need for fresh preparation, Hulthe’s method proved the most suitable under the testing conditions for application to cultural heritage paper objects. Careful assessment of ink or pigment migration remains essential to avoid misinterpretation of the results.
In a conservation project at the Austrian National Library, the condition of green colouration with copper-based pigments on printed maps was assessed in 163 atlases from the 17th century. The pigments of the atlases were characterised by copper indicator papers, XRF, and FORS. The condition of the cellulose fibres was studied with optical microscopy, SEM, and cellulose analysis with carbonyl group labelling. Based on the study of painters’ manuals for the green colouration of maps, test specimens were prepared, treated and submitted to accelerated ageing. The test specimens were evaluated visually, with optical microscopy, colour measurements, and cellulose analysis. The addition of alum and vinegar to solutions of verdigris produced degradation on flax-hemp paper comparable to the degradation observed on copper-green colouration in 17th century atlases. Nine atlases with severe degradation caused by copper-green pigments were selected for treatment with the complexing agent benzotriazole and for stabilisation with precoated Japanese tissue papers that contained the antioxidant tetrabutyl-ammonium bromide.
This study presents the findings of a field-based investigation on the preservation of historic Tibetan manuscripts in nine border monasteries within Shannan City, Xizang Autonomous Region, China. As repositories of sacred Tibetan manuscripts, these monasteries face increasing preservation challenges due to a harsh environment, the decline of traditional preservation models, a lack of special preservation funds, and insufficient collaborative efforts in the preservation of historic manuscripts. Through on-site visits and observations, both qualitative and quantitative data were collected to study and record the current status of the historic manuscripts in these monasteries. The problems of Tibetan manuscripts in border monasteries were identified, including the long-term marginalization of historic manuscript preservation efforts, the inaccessibility of historic manuscripts sealed away for preservation, the diminishing role of monks in manuscript preservation, and a breakdown in the transmission of traditional preservation knowledge. The paper proposes several practical suggestions to transform historic manuscript preservation in border monasteries from passive preservation to active use and cultural transmission. These strategies include strengthening legal protections, utilizing modern technology, encouraging the active participation of monks, and establishing specialized training systems. This study contributes to a broader discussion on the preservation of cultural heritage in marginal environments.
Abstract This study provides a material-based investigation into the transition of Greek manuscript production from the 11th through the 18th centuries, focusing on four examples preserved in the Pezaros’ Collection of the Historical and Paleographic Archive of the National Bank of Greece (MIET). Despite the advent of print technology during this period, manuscript production persisted as a living continuation of Byzantine calligraphic and illumination traditions, particularly within monastic centres such as Mount Athos, Epirus, and Crete. Advanced non-invasive and micro-analytical techniques (multispectral imaging and scanning electron microscopy with energy dispersive spectroscopy (SEM/EDS)) were employed to investigate traditional Byzantine practices. The study reconstructs the technical and cultural context of Byzantine and post-Byzantine manuscript production, highlighting the ways in which copyists and illuminators balanced continuity with adaptation. The research contributes to a deeper understanding of Byzantine and post-Byzantine material culture, offering insights into artistic practice, regional variation, and the evolving role of manuscripts until the age of print. Our study provides valuable information about the techniques and materials used in manuscript creation, while also assessing their preservation status. The inks used in the texts were identified, including cinnabar for red inks and iron gall ink for black-brown inks. Additionally, a variety of pigments commonly used during that period were determined, such as green earth and orpiment, which were found in the manuscripts.
Adhesive tapes have long been used in conservation mounting practice for various purposes, whether to attach exhibits to backing materials or to bond protective glazing. The type of application and selection of adhesive tapes not only reveal the conservator’s signature but are also an expression of the spirit of the times and the development history of the materials used. However, the aging of adhesives can pose risks to the durability of the bonds and to the exhibits themselves. This article presents the results of investigations into aged adhesive tapes using scanning electron microscopy, energy-dispersive X-ray spectroscopy (EDS), and infrared microscopy (IR), with a particular focus on papyrus glazing.
Abstract ATR-IR and Raman spectroscopic measurements were used to detect deposits of gypsum CaSO 4 ·2H 2 O and syngenite K 2 Ca(SO 4 ) 2 ·H 2 O in four handmade, gelatine-sized papers from about 1750 to 1850. The formation of gypsum and syngenite can be related to the use of potash alum (potassium aluminium sulphate (KAl(SO 4 ) 2 ·12H 2 O)) in the gelatine sizing of paper. The precise date of the introduction of alum in papermaking is still debated by paper historians due to lack of written evidence. Therefore, paper historians must rely on the examination of historical paper specimens themselves to find hints for the use of alum. Because the aluminium ions of alum are consumed in the sizing process, it is unlikely to find alum itself in historical papers. The detection of gypsum and especially of the potassium containing syngenite can indirectly confirm the use of alum and can help to find gelatine-alum sized papers from the earliest possible period.
This study investigated the effects of stone-calendering on the mechanical properties and shape stability of three traditional handmade papers (xuan, bamboo, and hanji papers). Stone-calendering is widely adopted to enhance paper softness and smoothness, yet its material-specific impacts on mechanical performance and shape stability remain underexplored. We evaluated three sample groups - untreated, stone-calendered, and wax-treated stone-calendered papers - under controlled conditions, analyzing their basic properties (density, optical characteristics), mechanical performance (tensile strength, folding endurance), and shape stability. Digital Image Correlation (DIC) technology quantified shape stability under humidity cycling and accelerated dry heat ageing tests assessed ageing resistance. Results show that raw material composition is a critical factor determining paper responses to treatments: stone-calendering increased density and softness while reducing surface roughness across all samples, but pre-calendering wax treatment compromised tensile strength (attributed to weakened inter-fibre bonding). While all paper samples exhibited progressive discoloration during ageing, wax-treated stone-calendered samples showed slightly higher color difference values than untreated and stone-calendered samples, suggesting a potential minor effect of wax components that needs further investigation. Notably, hanji exhibited superior shape stability after stone-calendering, especially under humidity cycling, whereas xuan paper displayed higher sensitivity to wax-induced ageing. These findings highlight fibre length- and material-specific responses of traditional handmade papers to waxing followed by stone-calendering, providing empirical data to inform paper conservation practice and guide the refinement of this traditional processing method in calligraphy/painting mounting crafts and processed paper production - by balancing calendering immediate aesthetic benefits with wax-induced impacts on long-term structural and ageing integrity, with all effects being subtle, fibre length-dependent, and within experimental uncertainty. Diese Studie untersucht die Auswirkungen von Gl & auml;ttung durch Steine auf drei traditionelle handgesch & ouml;pfte Papiere (Xuan-, Bambus- und Hanjipapiere) bez & uuml;glich ihrer mechanischen Eigenschaften und der Formstabilit & auml;t. Das Gl & auml;tten durch Steine ist weit verbreitet, um die Weiche und Gl & auml;tte von Papier zu verbessern, allerdings sind die materialspezifischen Auswirkungen wenig bekannt. Dazu wurden die drei Papierarten - unbehandelt, gegl & auml;ttet und mit Wachs behandelt und dann gegl & auml;ttet - unter kontrollierten Bedingungen auf ihre Basiseigenschaften (Dichte, optische Eigenschaften), mechanische Eigenschaften (Zug-und Falzfestigkeit) und Formstabilit & auml;t untersucht. Mit Hilfe von Digital Image Correlation (DIC) konnte die Formstabilit & auml;t der jeweiligen Papierprobe unter zyklisch schwankender Feuchtigkeit bestimmt werden, und mittels beschleunigter W & auml;rmealterung konnte die Alterungsbest & auml;ndigkeit des Papiers eingesch & auml;tzt werden. Die Ergebnisse zeigen, dass die Faserzusammensetzung die Reaktion der Papiere auf die ausgew & auml;hlten Behandlungen stark beeinflusst: Gl & auml;ttung mit einem Stein erh & ouml;hte bei allen Papierarten die Dichte und die Weichheit bei gleichzeitiger Verringerung der Oberfl & auml;chenrauhigkeit, aber die Behandlung mit Wachs beeintr & auml;chtigte die Zugfestigkeit. Diese Beobachtung wird auf eine Schw & auml;chung der Faser-Faser-Bindung zur & uuml;ckgef & uuml;hrt. W & auml;hrend bei allen Papieren eine fortschreitende Verf & auml;rbung im Verlauf der Alterungstests beobachtet wurde, war diese Tendenz bei den mit Wachs vorbehandelten und gegl & auml;tteten Papieren etwas st & auml;rker ausgepr & auml;gt. Dieser Aspekt sollte weiter untersucht werden. Hanjipapier zeigte auch w & auml;hrend zyklisch schwankender Feuchteeinwirkung eine gute Formstabilit & auml;t nach dem Gl & auml;ttungsprozess, w & auml;hrend sich Xuanpapier durch die Vorbehandlung mit Wachs w & auml;hrend der beschleunigten Alterung als etwas weniger stabil erwies. Diese Ergebnisse unterstreichen den Einfluss von Faserl & auml;nge und materialspezifischen Eigenschaften traditioneller handgesch & ouml;pfter Papiere auf die Ver & auml;nderung von Alterungseigenschaften, die durch den Einsatz von Wachs in Kombination mit Gl & auml;ttung durch Steine hervorgerufen werden. F & uuml;r die Praxis der Papierrestaurierung, der Kalligraphie, bzw. Montierung nach traditionellen Methoden und der Papierherstellung stehen somit empirische Daten zur Verf & uuml;gung, die bei der Abw & auml;gung von unmittelbaren & auml;sthetischen Verbesserung gegen & uuml;ber langfristigen strukturellen Ver & auml;nderungen helfen, wobei alle Auswirkungen subtil und abh & auml;ngig von der Faserl & auml;nge sind.
This study analysed the phenolic composition of iron-gall inks made from galls collected from Galicia and Catalonia, using High Performance Liquid Chromatography coupled with Mass Spectrometry (HPLC-MS) to identify and compare the relative concentrations of gallic and ellagic acids. Three historical recipes were reproduced, and the inks were subjected to two years of natural ageing. Significant differences in the phenolic profiles were observed, influenced by the geographic origin of the galls, the extraction method, and the solvent used. Inks made with Catalan galls showed higher relative concentrations of soluble phenolic acids. Gallic acid is primarily released through the hydrolysis of gallotannins, while ellagic acid can form through oxidative processes involving gallic acid. A higher relative amount of ellagic acid in certain formulations therefore suggests a more advanced oxidation process. These findings highlight the influence of regional ingredients and preparation methods on the chemical profile of iron-gall inks. Diese Studie untersuchte das Verh & auml;ltnis der phenolischen Bestandteile von Eisengallustinten, die aus Gall & auml;pfeln aus Galicien und Katalonien hergestellt wurden. Mittels Hochleistungsfl & uuml;ssigkeitschromatographie gekoppelt mit Massenspektrometrie (HPLC-MS) wurden die relativen Konzentrationen von Gallus- und Ellags & auml;ure identifiziert und verglichen. Drei historische Rezepte wurden reproduziert und die Tinten einer zweij & auml;hrigen nat & uuml;rlichen Alterung unterzogen. Es wurden signifikante Unterschiede in den phenolischen Profilen beobachtet, die durch die geografische Herkunft der Gall & auml;pfel, die Extraktionsmethode und das verwendete L & ouml;sungsmittel beeinflusst wurden. Tinten aus katalanischen Gall & auml;pfeln zeigten h & ouml;here relative Konzentrationen an l & ouml;slichen Phenols & auml;uren. Galluss & auml;ure wird prim & auml;r durch die Hydrolyse von Gallotanninen freigesetzt, w & auml;hrend Ellags & auml;ure durch oxidative Prozesse unter Beteiligung von Galluss & auml;ure entstehen kann. Eine h & ouml;here relative Menge an Ellags & auml;ure in bestimmten Formulierungen deutet daher auf einen fortgeschritteneren Oxidationsprozess hin. Diese Ergebnisse unterstreichen den Einfluss regionaler Ausgangsmaterialien und Herstellungsmethoden auf das chemische Profil von Eisengallustinten.
With the increasing use of recycled paper, its application as a permanent paper for archival purposes has been discussed. Although it was initially thought that recycled paper would not be of sufficient quality for this application, some permanent recycled papers are now commercially available. In this study, recycled papers with declared ISO 9706 standard compliance were purchased and their required properties were verified by laboratory testing. Moreover, a few additional tests not required by the standard were added. The results showed that half of the tested recycled papers are truly permanent according to the ISO 9706 standard and that their properties are comparable to those of the non-recycled paper standards. Therefore, their use for archival purposes should be safe according to the chosen standard. However, the ISO 9706 compliance of the rest of the tested recycled papers is at least questionable even though it was declared by the manufacturer. Consequently, when considering the use of permanent recycled paper, it is strongly recommended to verify its required properties through independent testing.
In this study, an alternative method for non-aqueous and non-alcoholic lining of paper documents is proposed, with Japanese tissue paper pre-coated with polyvinyl butyral (Butvar® B-76) adhesive used as the lining material. The adhesive layer is activated with a solvent mixture of dimethyl carbonate and n -hexane. The findings of the conducted tests indicate that the proposed method is safe with regard to the tested writing and printing media. Furthermore, it does not alter the paper structure or cause any deformation of the folios. In order to evaluate the effectiveness of the lining and the ageing characteristics of the pre-coated tissue, the mechanical properties of the lined samples, their colour stability, the pH values of the aqueous extracts and the removability of the lining tissue were tested both before and after accelerated degradation. The results were considered satisfactory.
Palm-leaf manuscripts served as a primary documentary medium across South and Southeast Asia prior to paper’s ascendancy. China’s Yunnan and Xizang regions preserve significant collections of these cultural artifacts; however, standardized conservation protocols remain underdeveloped. This investigation pioneers systematic analysis of incised palm-leaf manuscripts in Yunnan repositories, establishing a novel typology for damages and corresponding customized conservation strategies. Through empirical examination, five characteristic types of deterioration were identified. Aiming at restoring the structural integrity and functionality of palm-leaf manuscripts, the conservation strategy integrates damage classification, cleaning and stain removal, repair and reinforcement, flattening, binding restoration, and protective housing. The results demonstrate that composite fillers (palm-leaf’s powder, pulp, fiber strip, and infills) with chemical composition and physical properties matching those of the manuscript, ensure the compatibility of the repair materials. Additionally, the adhesives used in this study can be safely removed under specific conditions, effecting the reversibility of the intervention. These materials have sufficient durability under standard preservation conditions, ensuring the long-term stability of the restored areas. This study not only provides a feasible technical path for the conservation of palm-leaf manuscripts in Yunnan but also offers important guidance and references regarding conservation and preservation research for institutions worldwide that collect engraved palm-leaf manuscripts.
This study examines the preservation challenges and strategies implemented at the Library of the Kodaikanal Solar Observatory (KSO), part of the Indian Institute of Astrophysics. The library houses rare and sometimes fragile manuscripts, historical documents, and infrastructure of historical importance. Due to KSO’s distinct climatic conditions, specialized conservation measures were crucial in safeguarding these scientific heritage resources. A comprehensive approach combining preventive measures with chemical and non-chemical interventions was adopted. Key strategies included CO 2 fumigation to protect paper-based materials from pests and specialized pest control techniques to address threats like wood borers and termites, which endangered both collections and the library’s structure. Based on practical experience during the preservation process, this study offers workable solutions for libraries and archives. It emphasizes sustainable, integrated pest management practices that minimize environmental impacts while ensuring long-term preservation. Findings highlight the importance of continuous monitoring, early intervention, and eco-friendly solutions in preservation efforts. By presenting a structured methodology, this case study serves as a model for heritage libraries facing similar challenges. It advocates for a holistic approach to balance preservation techniques with the unique needs of heritage materials, ensuring their accessibility for future generations.
Depositories of cultural institutions contain written historical documents protected by enclosures against mechanical damage, solid pollutants, the effects of light, and fluctuations in temperature and/or humidity. A potentially suitable additive flame retardant has been developed for archival cardboards to reduce the loss of valuable documents during possible fires in depositories without fixed extinguishing equipment. Archival boxes made of solid cardboard were treated with two selected additive flame retardants: a mixture of natural bentonite and mica in a cellulose ether solution and an aqueous sodium silicate solution. Subsequently a medium-scale fire test was performed on treated and untreated box samples placed in archival shelves. The test conditions simulated a fire in a relatively large depository where the oxidizing agent is present for a long time and the combustion products can leave the area. The approximate time to ignition, the decrease in mass, and the increase in temperature in various parts of the shelves were measured. The flame spreading rate was recorded and the final condition of the archival boxes and their contents was evaluated. The mixed flame retardant delayed ignition, slowed the combustion, and protected most of the archival boxes against burning; moreover, prior examination did not exhibit a substantial detrimental effect on the cardboard properties.
This study proposes a combined treatment based on Persian gum known as zedu that aims to combat some of the main factors contributing to the deterioration of paper-based cultural heritage. Persian gum was used as a reinforcing agent to restore the mechanical strength and stability of paper. The research is a practical study with an analytic-comparative approach testing mechanical strength, resistance to biological attack, and color changes according to standard protocols. Nanoparticles of zedu with varying weight percentages were extracted and combined with calcium hydroxide and glycerol to enhance pH and flexibility. The extract of Satureja khuzestanica was tested for its effectiveness against biological degradation. A treatment solution was applied to paper samples, which were subjected to artificial aging under humidity and temperature conditions following ISIRI-4706 for six full days, and light exposure for 4 days. Measurements revealed an increase in tensile strength depending on the amount of the gum used. Colorimetric measurements indicated minimal color changes for the treated and untreated samples before and after aging. Furthermore, the study demonstrated the inhibition of common fungal growth on treated paper at concentrations of 500 and 100 µl of S. khuzestanica extract.
A survey of the document preservation technique referred to as encapsulation was conducted of United States institutions with catalogued archives and paper collections. The purpose of this survey was to inform: an estimation of the proportion and type of materials and documents encapsulated, the popularity of various methods and the materials used for encapsulation creation, and the condition of encapsulation materials and encapsulants in collections. The survey responses provided the first data pertaining to the state of encapsulation approximately fifty years after encapsulation for preservation was formally developed. Survey results suggest that: encapsulation is well-established and highly valued in the toolbox of preservation strategies yielded by conservators and collection managers; that most encapsulation construction materials used during the past fifty years evidence few deterioration problems such as yellowing or embrittlement; that it is not a frequent occurrence that conservation treatments like deacidification, washing or the introduction of pollution sorbents is common; and that there is general satisfaction with encapsulation as a preservation method for weakened paper, maps and posters, whether the encapsulation is used in an archival or exhibition environment. Several text responses from survey participants expressed that future research on polymeric material stability and permeability may alleviate some concerns regarding future use of encapsulation. In amerikanischen Archiven und Sammlungen wurde eine Umfrage zu Folientaschen durchgef & uuml;hrt, die in den USA h & auml;ufig zur Aufbewahrung und Stabilisierung von br & uuml;chigem Papier eingesetzt werden. Dabei werden die entsprechenden Papiere in einen Umschlag aus durchsichtigem Kunststoff lose eingelegt. Ziel der Umfrage war es, Informationen & uuml;ber folgende Aspekte zu erhalten: den Anteil und die Art der so behandelten Dokumente, die Beliebtheit der verschiedenen Arten von Folientaschen, die daf & uuml;r verwendeten Materialien sowie den Zustand der behandelten Dokumente. Die Antworten auf die Umfrage lieferten erste Daten & uuml;ber den Stand der Verwendung von Folientaschen etwa f & uuml;nfzig Jahre nach der Entwicklung des Verfahrens. Die Ergebnisse der Umfrage zeigen, dass Folientaschen gut etabliert sind und im Rahmen von Strategien zur langfristigen Erhaltung von Papierobjekten h & auml;ufig eingesetzt wird, dass die meisten in den letzten f & uuml;nfzig Jahren dabei verwendeten Materialien nur wenige Degradationsph & auml;nomene wie Vergilbung oder Verspr & ouml;dung aufweisen, dass konservatorische Behandlungen wie Ents & auml;uerung, Wasserb & auml;der oder das Einbringen von Schadstoffabsorbern nicht h & auml;ufig in Kombination damit durchgef & uuml;hrt werden und dass der Einsatz von Folientaschen als Erhaltungsmethode f & uuml;r fragile Dokumente, Karten und Plakate im Allgemeinen gut geeignet ist, unabh & auml;ngig davon, ob sie im Archivierungs- oder Ausstellungskontext eingesetzt wird. In mehreren Antworten der UmfrageteilnehmerInnen wurde zum Ausdruck gebracht, dass k & uuml;nftige Forschungsarbeiten zur Stabilit & auml;t und Durchl & auml;ssigkeit von Polymermaterialien einige Bedenken hinsichtlich der k & uuml;nftigen Verwendung von Folientaschen ausr & auml;umen k & ouml;nnten.
This article discusses traditional ways of caring for historical palm leaf manuscripts ( takepan ) made from palm leaves ( lontar ) in the Lombok region, West Nusa Tenggara, Indonesia. Data were collected using interview and documentation methods. Ethnographic thematic analysis was chosen to describe the cultural characteristics of communities which foster a long tradition of caring for manuscripts. For this purpose, manuscript owners use a wide variety of local materials, including komak ( Lablab purpureus (L.) Sweet), kara ( Canthium coromandelicum ), or urang aring ( Eclipta prostrata (L.) L.) leaves, charcoal from coconut fiber, oil from lemongrass ( Cymbopogon citratus ), and candlenuts ( Aleurites moluccanus (L.) Willd.), and used engine oil. Methods of caring for manuscripts using various natural materials have been practiced for a long time, demonstrating the ongoing appreciation for and relevance of takepan manuscripts.
Bamboo paper is one of the most important types of traditional handmade paper in China. The manufacturing processes of bamboo paper can be categorized into cold digestion (uncooked) and hot digestion (cooked) methods. Different production processes have different effects on the properties of paper. This article studies the effects of different processes on the properties of bamboo paper through scientific experiments on basic physical properties, mechanical properties, pH, degree of polymerization, optical properties, chemical structure, crystalline structure, microscopic morphology, and aging resistance of bamboo paper produced by different processes. The results showed that cooking, post-fermentation, and bleaching in the papermaking process were the main factors affecting the properties of bamboo paper. Paper prepared from cooked pulp is superior to paper prepared from uncooked pulp in terms of pH, folding endurance, crystallinity indices, and aging resistance, but long post-fermentation processes and chemical bleaching would have adverse effects on the physicochemical properties and aging resistance of cooked paper. The research results showed that the key to making high-quality bamboo paper lies in the repeated weak alkali cooking of raw materials, a short post-fermentation process, and the minimal use of strong chemical bleaching agents.
Medieval manuscripts are an essential part of Persian cultural heritage and a rich source of the country's material culture. Their study sheds light on shared materials across the Mediterranean and Near East. The practice of using blue and purple in manuscripts was popular during the Middle Ages in both Europe and Persia. Persian historical treatises describe a blue dye plant used for paper, in addition to blue indigo, although its specific terminology was previously unknown. The plant is identified as Chrozophora tinctoria (L.) A. Juss., also known as turnsole; the dye extracted from it is commonly known as folium. This study is divided into three phases: First, dye extraction techniques from C. tinctoria fruits were studied based on historical Persian recipes. Second, methods for reconstructing blue-purple paper dyes from turnsole fruits were explored, with local plants harvested in Iran during August and September, and the dyes analysed using spectroscopy, finding a good agreement to folium spectra obtained from European (central Italy) fruits of C. tinctoria. Third, folium was identified on manuscripts produced under Islamic rule in the Middle Ages. The findings suggest discussion as to whether this dye was used in Persian manuscripts too, given the notable corpus of citations in Persian historical treatises. Mittelalterliche Handschriften sind ein wesentlicher Bestandteil des persischen Kulturerbes und eine reiche Quelle f & uuml;r die Erforschung des materiellen Kulturerbes des Landes. Das Studium mittelalterlicher Handschriften wirft ein Licht auf gemeinsame Materialien im Mittelmeerraum und im Nahen Osten. Die Verwendung von Blau und Purpur in Manuskripten war im Mittelalter sowohl in Europa als auch in Persien beliebt. Persische historische Abhandlungen beschreiben eine blaue F & auml;rbepflanze, die zus & auml;tzlich zu blauem Indigo f & uuml;r Papier verwendet wurde, obwohl ihre spezifische Terminologie bisher unbekannt war. Die Pflanze wird als Chrozophora tinctoria (L.) A. Juss. identifiziert, die auch als Lackmuskraut bekannt ist; der aus ihr gewonnene Farbstoff wird gemeinhin als Tournesol oder Folium bezeichnet. Diese Studie gliedert sich in drei Phasen: Zun & auml;chst wurden die Verfahren zur Extraktion von Farbstoffen aus Chrozophora tinctoria Fr & uuml;chten auf der Grundlage historischer persischer Rezepte untersucht. Zweitens wurden Methoden zur Rekonstruktion von blau-violetten Papierfarbstoffen aus den Fr & uuml;chten des Lackmuskrauts untersucht, wobei lokale Pflanzen, die im August und September im Iran geerntet wurden, verwendet wurden. Die Spektren der daraus gewonnenen Extrakte zeigen eine gute & Uuml;bereinstimmung mit den Foliumspektren, die aus europ & auml;ischen (mittelitalienischen) Fr & uuml;chten von Chrozophora tinctoria gewonnen wurden. Drittens wurde Folium auf Manuskripten identifiziert, die unter islamischer Herrschaft im Mittelalter hergestellt wurden. Die Ergebnisse regen zu einer Diskussion dar & uuml;ber an, ob dieser Farbstoff auch in persischen Handschriften verwendet wurde, da es in persischen historischen Abhandlungen eine beachtliche Anzahl von Verweisen darauf gibt.
