X-ray technology to shed new light on ancient stone inscriptions
August 02, 2005 (PhysOrg.com)
In an unusual collaboration among scientists and humanists, a Cornell University team has demonstrated a novel method for recovering faded text on ancient stone by zapping and mapping 2,000-year-old inscriptions using X-ray fluorescence (XRF) imaging.
The chosen inscriptions -- one in Classical Greek and two in Latin -- each presented different levels of wear. XRF imaging detected minute amounts of iron, zinc and lead in the inscribed regions, among other elements. Iron chisels were commonly used to inscribe the stones, and the letters were usually painted with pigments containing metal oxides and sulfides. These may account for the iron and lead, but the source of the zinc is a mystery. In the most worn stone, the trace elements measured by XRF clearly revealed the contours of the original letters, even where they were no longer visible to the eye. For modestly worn stones, XRF imaging will help to decipher texts and may provide new information on how the inscriptions were made.
"This means restoring thousands of stones, including, possibly, part of the law code of Draco," said Clinton. Draco was a seventh-century Athenian politician who codified the law of Athens. "It applies to practically any kind of public document you can think of, including many laws, decrees, religious dedications and financial documents."
The research is being published in this month's Zeitschrift fur Papyrologie und Epigraphik.