Charters,” GU Archive Services, last accessed April 15, 2013., - PDF document

1. “The Blackhouse Charters,” GU Archive Services, last accessed April 15, 2013., http://www.gla.ac.uk/services/archives/collections/university/features/blackhouse/ 2. Betty M. Haines, Parchment ( Northmapton : The Leather Conservation Centre, 1999), 11 - 12. 3. Ibid. 31 - 32 THE BLACKHOUSE CHARTERS CONSERVATION PROGRAMME – PARCHMENT PRESERVATION Kacper Ku ź nicki Making and the Meaning: Approaches in Technical Art History 2012 - 2013 Parchment is a mechanically and chemically processed animal skin. It consists of collagen which is the dominant animal connective tissue. Collagen is a polymer composed of about twenty amino - acids of which the most characteristic three are glycine, proline and hydroxyproline . A single molecule of collagen forms a triple helix consisting of three basic chains of amino - acids linked by peptide bonds. 2 BL.360 – mounted on a museum board and placed in the folder All photographs were taken by the author of this poster. Particle models belong to the public domain and are free to copy and use for any purpose. Acknowledgements: Thanks to El ż bieta G ó rska - Wiklo , Preservation Manager, University of Glasgow Archive Services. Repacking the parchments into custom made, archival quality folders ensures safe and spacious storage conditions. Mounting parchments onto individually prepared boards not only contributes to their preservation, but also makes parchments easier to handle and ready for museum display should such necessity arise. New packaging meets expectations of various parties: archivists, conservators and curators. Detail of stiffened parchment strips of BL.388 BL.388 examined under ultra - violet light Detail of ink on BL.361 seen under a microscope (x50) BL.110 observed in raking light Securing BL.390 onto a storage board using clear plastic strips. Author securing the BL.390 seal with strips of plazstazote. Damage to the parchment and seals can be caused by a number of physical and chemical factors. Collagen is vulnerable to humidity. When exposed to excessive amounts of water it undergoes hydrolysis resulting in irreversible gelatinisation. Gelatinised parchment is very stiff, discoloured and translucent. Wax seals often suffer from mechanical damage. Too much pressure, high temperatures, inaccurate handling and inappropriate storage conditions may result in cracks, staining and flattening of the relief. Although the seal may initially seem intact those factors slowly wear the wax down. The ultra violet light examination is a useful way of revealing otherwise invisible changes. Repairs and retouches emanate a strong vivid glow and the presence of moulds and fungi can be confirmed by their characteristic purple or orange fluorescence. Remnants of old paper wrapping could be seen as light white specks. Not all holes and openings are damage. Some are of natural origin and some are an outcome of manufacturing process. Shape, texture of the edges and the flow of text indicate the nature of the opening. Maker’s hole resulted from stretching the parchment during scraping phase. Strongly gelatinised edge of BL.360 Yellow diagonal line visible above resulting from folding the parchment. Photo taken with a digital microscope (x50) Damaged seal of BL.360. Example of mechanical damage. Photo taken using a digital microscope (x50) BL.107 examined under UV. Visible stains resulting from humidity and signs of fungal presence seen on the decorative cross. There are several factors influencing parchment deterioration. Moisture leads to gelatinisation and mould growth. Dry environment results in irreversible embrittlement . Exposure to sunlight leads to photodegradation and acidic atmosphere may cause oxidation of collagen molecules. 3 The Blackhouse Charters are amongst the most significant land ownership and property documents in the UK. They cover an impressive timespan extending between the reigns of King Robert the Bruce (1306 - 1329) and Queen Anne (1702 – 1714). 1 As such they constitute one of the greatest treasures of the Archive Services and their preservation is paramount. The collection of 499 documents is currently undergoing a conservation programme. Each of the documents requires a detailed condition assessment and then depending on its state, it is either repacked or subjected to treatment. Maker’s hole in BL.370. Oval shape, gelatinised edges and the text encapsulating the opening indicate it occurred during parchment manufacture. Many of the documents were executed on parchment. My project focuses on this medium. It was my task to prepare condition reports of thirty parchment documents. I was also responsible for repacking them. Damage assessment is a complex process, many changes are not obvious at first sight and some destructive processes remain invisible to a naked eye. Non - invasive examination techniques such as UV light, raking light examination and microphotography supported my work. Detail of BL.390 wax seal seen under a microscope (x50) During the course of the placement I have gained a number of skills including object handling, condition assessment, applying modern object examination methods and package preparation and repacking . I have also gained theoretical understanding of the parchment medium.