 Hello. Excuse me. My name is Alicia Walker. I am the Interim Chair and Professor of Medieval Art History at Bryn Mawr. I'm so pleased to be here today to introduce my student, but I would first just like to thank the co-organizing institutions Temple and especially Penn for this wonderful event. I'm so happy to be here and to hear all these wonderful papers. So I'm pleased to introduce Shannon Steiner, who is in her final stages of the PhD at Bryn Mawr College. Shannon completed her BA down the road at Temple University and her MA at the University of Texas Austin before coming to Bryn Mawr. Her work is focused on issues of materiality in the devotional objects of early and middle Byzantine society and she has researched and published on tokens from the pilgrimage site of the St. Simeon and on gold glass medallions embedded in the walls of early Christian catacombs in Rome. Today she will present aspects of her dissertation research in which she is exploring the technical and ideological aspects of Byzantine enamel and how the understanding of enamel is a technical scientific art informed its meaning in Byzantine religious and political culture. Since her first year doctoral studies, Shannon has held the prestigious Saratay Graduate Fellowship at Bryn Mawr and in addition she has pursued her dissertation research with the support of a two-year Crest Foundation institutional fellowship at the Central Institute for Kunstgeschichte in Munich, a Mary Jeharis Center for Byzantine Art and Culture Dissertation Grant and the Summer Institute in Technical Art History participation in that program which is sponsored by the Conservation Center of the IFA. She currently holds a junior fellowship in Byzantine studies at Dunbart-Nokes in Washington, D.C. where she has her nose in the books and her fingers on the keyboard as she completes her dissertation research and writing but where she is also engaged in hands-on work with a group of contemporary metalsmiths to explore the technical aspects of Byzantine enamel work through the reconstruction of medieval artisanal practices and the production of original enamel objects using these historical methods. Her talk today is titled, Reified Knowledge, Byzantine Enamel as a Staticized Technology. I mean just a second I lost my microphone when I stood up. A little bit awkward but we'll work through it. All right, I'm giving up. Thank you Professor Walker for that introduction and I'd also like to extend my thanks to the Barnes and to Temple and University of Pennsylvania in addition to Bryn Mawr for organizing this and especially to Bryn Mawr for their support. So renowned for its sumptuous beauty and radiant brilliance, cloissanet enameling is a technique distinctive to Byzantine art production and its use was kept restricted to the highest echelons of Byzantine society. Byzantine goldsmiths were matchless in their ability to fuse vividly colored glass to golden plaques divided into cells by delicate strips of pulled wire. The French term cloissanet refers to these cells or cloissons which render the complex designs of this medium within a shimmering tracery. Soon after enamel production began in earnest around the mid 9th century goldsmiths rapidly developed an unprecedented range of glass colors often varying its transparency and translucency from one cell to the next. Wire was thinned to a minute width that allowed for pictorial compositions unparalleled in their degree of detail which you can see here which is itself a detail of a much larger object. This is a very small section of it. Each of these innovations required deep familiarity with the properties of natural substances such as gold, metal oxides and salts and even fire and heat. Enameling also demanded proficiency in manipulating those materials into impressive displays of artistic ingenuity. In my paper today I consider how Byzantine enamel could bear unique meaning through its display of the rarefied knowledge required to produce cloissanet and the skill evident in its execution. It is important to note that while scholars often describe enamel as a material in its own right, it is more accurately defined as an artistic process. Following the work of historians of early modern art and science, most notably Pamela H. Smith, I consider processes of making to be crucial occasions for the creation and demonstration of knowledge. Knowledge of materials, of iconography and a self aware knowledge on the part of the artist of his own ability to overcome the challenges presented by both, something we would call skill. Within this understanding, I posit that Byzantine enameling was aestheticized technology. Indeed, the Greek roots of the word technology embody this understanding. Technique meaning art or skill and logos meaning knowledge bespeak the processes of display and making that I argue are realized in the visual and material properties of Byzantine cloissanet enamel. Technology and process where the concepts through which enamel was defined in Byzantium, the terms for enamel in Byzantine literature, himmephton and area himmephtah derive from the verb heal to flow poor or melt. They can be translated literally as melted things or melted work. However, the stem of the words and their etymological origins link them to himia and hemesis, the medieval Greek terms for alchemy. An alternative translation of Byzantine enamel vocabulary might then be things by himmephtis or more simply alchemical things and alchemical work. The relationship between enameling and alchemy in Byzantium was more than just etymological. Byzantine texts on the subject of alchemy survive and they contain recipes and instructions for enameling that scholars have noted, but that have not been discussed in any great detail. In the 19th century, French chemist Marceline Bertelot compiled, edited and translated the collection des enseignes alchemist Grec, known today as the Greek alchemical corpus. The manuscripts range and date from the 11th to 15th centuries. Each is a compilation or miscellany rather than a single authored composition. And the texts contain within them date through the second through 13th centuries. Bibliotheca Marchiana's Greicus to 99 and Paris Greicus 2327, shown here with their really fantastic depictions of alchemical imagery and apparatus are the two best known Byzantine alchemical manuscripts. Now, defining exactly what the practice of Byzantine alchemy entailed is difficult. The education and social demographic of Byzantine alchemical authors also remains mysterious, but the practical technical nature of many of these texts suggests that the authors observed working artisans and may have even collaborated outright with them in experimental endeavors. The subject of chrysopia or gold making abounds within the alchemical corpus, but in late antiquity in Byzantium, alchemical practice was not restricted to transmuting based metal into gold. Interspersed throughout are a wide range of recipes and commentaries for processes involving some kind of physical transformation, such as making silver, fabricating gemstones and pearls, making purple dye, baking bread and creating explosives. Most importantly, from my study of Byzantine enamel, much of the alchemical corpus examines how to artificially reproduce physical qualities and behaviors of natural matter. Now, artifice is the key term here. Artifice and artificiality today carry strong connotations of inauthenticity and even deception. Something artificial can't be genuine, and what is artificial is often considered antithetical to nature. In the Byzantine alchemical corpus, we see none of these modern judgments. Instead, what is artificial is that which is made through human action and human intention, rather than spontaneously occurring in nature. Far from being at odds with nature, Byzantine alchemical writings often signal that man-made replications of natural phenomena were proof of fully comprehending and even mastering nature. The enamel recipe that I will speak about today is especially evocative of this belief in the power of artifice, a belief that had a long history in the Byzantine world stretching as far back as the first few centuries CE. One of the earliest proto-alchemical treatises to survive from late antiquity is the fourth century Stockholm papyrus, a compilation of instructions on making gold, silver, purple dye, and gems. One of the most compelling features of the Stockholm papyrus is the author's unabashed celebration of the artificial. In the course of listing ingredients and methods for coloring glass and quartz into convincing imitations of rubious sapphires and emeralds, the author of the papyrus often states that the final product will surpass the natural kind. This could just be a cheeky boast on the part of the author's ability to fool ignorant viewers. Yet glass enhancements and imitation gems appear with such regularity and sophisticated late Roman and Byzantine goldsmiths work that they seem unlikely to have gone unnoticed. Colored glass could be adhered to valuable rock crystal to enhance the visibility of carving and intensify the natural crystals reflectivity as seen in a pendant now in Dunbarton Oaks. This practice is known in goldsmithing as creating doublets and is an artificial intervention made for the purpose of enhancing a stone's natural visual qualities and preventing scratches and breakage. Artificial glass emeralds are incorporated alongside genuine garnets and sapphires on an intricate 10th century earring or diadem ornament now in Athens. And a recent analysis of a 7th century jewel re-hoard using Roman spectroscopy revealed gemstones previously thought to be emeralds and lapis lazuli to in fact be glass imitations. So the necklace is genuine emerald but the the earrings up here, those are glass. It is possible that the makers and owners of these expensive luxury jewels were duped by some dishonest artisan but a more intriguing possibility is that artificial replications of precious natural materials had a value and power of their own. This notion lies at the heart of a hitherto unidentified recipe for enameling in the Greek alchemical corpus and these are the two manuscript pages of the beginning of this treatise. Imitation gems are the central focus of this treatise elaborately titled The Deep Dying of Stones, Emeralds, Rubies and Sapphires, according to the book taken from the inter-sanctuary of the temple and that's significant but I don't have time to talk about it today. The treatise contains certain Arabic loanwords and other philological signatures that place its date somewhere between the 8th and 10th centuries, a moment when the volume of Byzantine enamel production intensified. The text is a long anthology of recipes for artificial gems attributed to semi-mythological alchemists such as the Egyptian priest Ostanis or a Jewish female alchemist named Maria. The text is arduous and somewhat fragmented in its current state of addition but its format is very regular. Each recipe for a stone is preceded by a theoretical explanation of a stone's natural properties. In most cases, color is emphasized as a distinguishing feature and then this is then followed by a list of ingredients that can approximate that effect when applied to either glass or crystal. In other words, the recipes are offered as an explanation of how to reproduce the natural phenomena described above it. The instructions for enameling are preceded by a theoretical investigation not of color but of luminescence. Concerning the making of emerald, just as Ostanis, the keeper of all things, Arcane, thinks, the ingredients used are copper rest and the bile of all sorts of animals and things like that. For sapphires, the ingredients used are the hyacinth plant and woad root boiled together. For rubies, the ingredients used are alkanet and dragon's blood. That's a resin, not actual dragon's blood. It's a bit clearer in these things. For the rubies that is called both night shining and sea dyed, the ingredients used are the bile of sea creatures, fish or whales, on account of their luminescing at night and their lustrous gleaming as their entrails, their scales and their bones clearly shine at night. This passage summarizes the ingredients of the recipes that came before it, before launching into an evocative description of a naturally fluorescing stone and the bioluminescence of sea creatures. While the author focuses on the replication of color in ordinary emeralds, sapphires and rubies, his concern with this mysterious night shining ruby is its autonomous generation of light. He continues. But from where do the stones receive their fiery brightness? Neither bile nor copper rest have the ability to grant this property, being green by nature. What do we say? Did such an important process elude Maria? No. She wrote on fabricating rubies. She also described it above. Here the artisan explains to us that the most precious stone appropriate to make and die is that which at night emits rays of light in the matter of the sun and those being in possession of it have the ability to read and write and do anything nearly as well as they do in the day. For each ruby has the property of shining at night according to its particular size and clarity, whether it is natural or artificial. But the property of shining at night belongs uniquely to the night shining ruby. Ruby, excuse me. So how to make sense of this description of a supernatural shining stone? What's this business with fish bile and what has it got to do with enamel? First, it's clear that the author of this text was not an artisan and was instead collecting knowledge of the causes of interesting natural phenomena and the techniques for reproducing them. Second, there is a pattern of material sympathy in the ingredients. So, for example, by the author's logic, the fact that some sea creatures are bioluminescent proves that the stone's luminosity is natural, not abnormal, and that the addition of fluids from those animals to a process would help to synthesize that effect in the final product. And this passage is not a complete flight of fancy. Given some clues in other parts of the passage where the ruby that shines at night is also called a sapphire, I believe that the author is describing fluorite. When seen in daylight, fluorite has a varied blue, green, purple hue. After hours of UV absorption, it glows a bright watery green. While no Byzantine objects made of fluorite survive, the stone was well known in classical antiquity and was popular for its use in luxury objects such as the first or second century Crawford and Barber Cups, found in a tomb in Anatolia where the stone is plentiful. However, I do not believe that Byzantine enamel was understood as artificial fluorite in a literal sense. It's not the stone that fascinates the author of the treatise, but rather the fluorite's natural quality of emitting its own light. This is a wondrous yet natural phenomenon that the stone shares with bioluminescent sea creatures, which the author identifies as particularly valuable. The recipe for enamel that follows prioritizes the reproduction of bright light over all else. It reads, take three liters of lead oxide, one liter of clear glass, two hexagia of tin and about a poos of finely ground sulfur. Put them in a clean small cup and heat them over charcoal until it becomes green glass. If the heating is extended, it becomes golden. If extended even longer, white like crystal. This recipe describes how to color the glass that an artist would grind and mix with water to fill the cells of an enameled work. The dominant additive to the glass is lead oxide, an ingredient that not only improves the feasibility of glass, but also dramatically increases its transparency and refractive index, allowing light to bend rather than just reflect and thereby enhancing effects of luminosity. With this in mind, a thoughtful arrangement of glass in relation to the direction of the reflective metal around it can capitalize on very little light in order to artificially simulate the autonomous glowing of a natural stone. This is seen especially in the brilliant green glass so prevalent in Byzantine enamels, exemplified by a mid-ninth century reliquary of the true cross. The glow of Byzantine enamel is difficult to photograph, not least of all because it's difficult now to see them in low lighting, but I attempted to generate this effect in the image on the right through very dim, indirect light. Under these conditions, the placement of the wire that formed inscriptions caused the letters to dissolve into unexpectedly, almost disproportionately bright light behind the heads of the saints that populate the reliquary's lid and sides. This technical strategy persists in the most accomplished of Byzantine cloisonnay, for example in the 11 extant medallions from an icon frame. X-ray imaging has revealed the presence of wire hidden beneath the surface of the glass fill in all of the medallions, seen here on the medallion of Saint Demetrius in the saints halo, hair, cheeks, and hands. In addition to securing the glass flux around them, the wires in the halos achieve the same refraction of light seen in the true cross reliquary when the halos are filled with green glass. But in this instance, the light follows the graceful loops and swirls of the wire between minuscule crosses and tiny circles. In both the reliquary and the medallions, the enameling goldsmiths demonstrated a consciousness of the kinds of natural qualities the Byzantines valued knowledge of and deployed their own skill and knowledge of materials to bring those qualities into existence. Here, enamel does not merely imitate a stone, but rather exhibits Byzantine understanding and control over a particularly powerful attribute of a stone by manifesting it through man-made means. To conclude, my approach to Byzantine enamel introduces a new understanding, not only of the medium as a material, but to the medium as an alchemical process. In objects and in texts, enamel embodied and offered proof of Byzantine knowledge of how natural materials and their physical qualities worked. Knowledge, understanding, and reproduction of nature was a primary goal of Byzantine alchemy. This allows us to understand enameling as a technological process of artificial reproduction, one that was part of a larger endeavor that could take nature itself and rearrange it into new configurations that highlighted Byzantine control and mastery over the natural world. Thank you.