Romanian researchers took some of the most modern analysis tools available and directed them into the past, scanning an old, deteriorated and fragile Jewish manuscript to learn how the handwritten document was produced, and discovering the concoction used for its ink.
The noninvasive exploration of the “severely degraded Jewish manuscript of unknown history” was able to comprehensively identify the materials used to produce the parchment as well as vital information on its state of preservation.
As part of their research the scientists developed a method for reconstructing lettering that they hope may be applied to other similarly faded manuscripts, aiding their preservation.
Maria Cortea, Luminiţa Ghervase, Lucian Ratoiu and Roxana Rădvan of the National Institute for Research and Development for Optoelectronics – INOE 2000, Măgurele, Romania published the results of their work on the Frontiers peer-reviewed website on Thursday, complete with photographs.
“A Jewish parchment scroll coming from a private collection was investigated using a multi-technique approach,” they wrote. “The parchment, significantly degraded, includes chapters from the Book of Esther also known in Hebrew as Megillat Esther.”
The parchment, measuring 62×52 centimeters (24×20 inches), is in the form of a scroll, and contains the first three chapters of the Book of Esther and the start of chapter four.
Regarding its history “not much is known, but the fact that the scroll was intended with a liturgical purpose,” they wrote, without dating the artifact.
The delicate parchment was subjected to multi- and hyperspectral imaging, Fourier transform infrared (FTIR) spectroscopy, and X-ray fluorescence (XRF) spectroscopy to uncover as much as possible of its construction.
Infrared light revealed that two types of inks had been used: first iron gall ink and, later, carbon-based ink, which was applied to make corrections or later additions, “most probably due to degradation and fading of the initial inscriptions.”
“In accordance with ancient Jewish parchment preparation techniques, the use of calcium sulfate, vegetable tannins, and oils was also inferred from the registered infrared spectra,” the researchers found.
Further analysis of the ink, using a technique known as X-ray fluorescence, revealed that in addition to iron, the authors used sulfur, potassium, magnesium and zinc in the recipe to prepare the ink. It also shone a light on the method used to prepare the skin, revealing that “a bleaching process with cooked zinc white could have been applied.”
“Vegetable tannins and oils could also be inferred from the registered infrared spectra, in accordance with ancient Jewish parchments preparation techniques,” the researchers wrote.
The data gleaned from the research helps provide a historic context for the undated manuscript and also information that can be used for better restoration and a long-term conservation strategy “of this severely damaged object.”
The team also developed a special algorithm that showed “promising results” in guiding them toward reconstructing the faded lettering.
The method provides “a potential valuable tool for the investigations of parchment manuscripts whose text is hardy visible or partially lost due to extensive degradation,” the researchers wrote.
The Book of Esther, which tells the story of Jewish deliverance during the Achaemenid Persian Empire in around the 5th century BCE, is traditionally read from a handwritten scroll as part of the Purim holiday. In 2021 the one-day holiday begins on February 25 in most places, and a day later in some locations, including Jerusalem.