New X-Ray Technology Unlocks the Door to Ancient Mysteries

Ancient scribes who carved their thoughts and beliefs into stone may have thought they were being permanently etched forever for future civilizations to ponder over. But through centuries, much of the material carved into stones by previous cultures has been lost simply because of weathering and the ravages of time.

Scientists and archaeologists estimate that there may be more than half a million Latin and Greek stone inscriptions throughout the world that are unreadable because they have decayed through the years and the inscriptions are now illegible.

One group of tablets that are difficult to read are the writings of Draco, a politician in Athens who was responsible for documenting the laws of the ancient civilization. Although Draco did not create the laws, he codified them for the Greek society, and now they give us a glimpse into the severity of the laws in Athens.

In fact, the word "draconian"- which means "cruel" - has its root in Draco's name. Minor offenses could result in a death penalty, and if citizens became overwhelmed with debt, they could be sold as slaves to pay their debts.

A new technique, called x-ray fluorescence imaging, was developed by researchers at Cornell University to make it easier for scientists to read faded inscriptions on ancient stones. Kevin Clinton, a professor of classics at Cornell, co-authored a journal article describing the technique.

The technique involves firing an x-ray beam at a stone and scanning the beam back and forth across the surface. The atoms on the surface of the stone emit fluorescent x-rays of a low energy. Wavelengths of a different frequency reveal iron, zinc, and various other elements in the stone.

Ancient scribes often used iron chisels to carve into stone, and they usually painted on stone using pigments composed of sulfides and metal oxides. Therefore, in places where numbers and letters can no longer be deciphered in stone carvings, the minerals revealed by the fluorescence imaging machine can now show their shapes.

An x-ray fluorescence imaging machine generates x-ray beams of an intensity that is a million times stronger than those of standard medical x-ray machines.

Researchers refer to the machine's process as "zapping" the stones and then "mapping" the resulting revelations. Tests were conducted on tablets which were thousands of years old, and scientists clearly saw writing that could not be seen with the naked eye.

Scientists believe that x-ray fluorescence imaging will soon become an important tool used in epigraphy, the study of writing carved into stone and other surfaces. The process is much more powerful and reliable than any previous technique.

"This means restoring thousands of stones, including, possibly, part of the law code of Draco," Clinton says. "It applies to practically any kind of public document you can think of, including many laws, decrees, religious dedications and financial documents".