maximus otter
Recovering policeman
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A gold-plated pendant thought to date back to the late 12th century has been analyzed using a neutron-based imaging technique, revealing its innermost secrets for the first time. The painstaking work was conducted by a team from the Leibniz-Zentrum für Archäologie at the Technical University of Munich.
The ornately decorated pendant was first unearthed in 2008 in the German city of Mainz, in the remnants of a medieval rubbish dump. It was immediately obvious that the pendant had been designed to open like a locket – but, frustratingly, centuries worth of damage meant that revealing its contents would be no easy feat.
The first [technique used] was neutron tomography. Similar to computed tomography (CT) scans that are used in medicine, this is an imaging technique that allows the internal structure of objects to be visualized. When conventional X-rays were not enough to know for sure what was inside the pendant, the restorers used this more advanced method.
The second technique is called prompt gamma-ray activation analysis (PGAA). A beam of neutrons is fired at the object being studied. Some of the neutrons are absorbed by the nuclei of the different chemical elements the object contains, in a process called neutron capture. Almost immediately (hence “prompt”), these new compound nuclei release a burst of gamma rays, which returns the elements to their previous state. The PGAA apparatus measures these gamma rays using a detector made of germanium, so researchers can determine the presence and amounts of different elements in the object.
Neutron tomography and PGAA revealed that there were tiny packages inside the pendant, containing fragments of bone.
The neutron tomography images revealed five packages inside the pendant. Image credit: Burkhard Schillinger, MLZ
Add to this the decorative images of Jesus and other Christian figures that adorn its outer surfaces, and the team suspects that the pendant may have been a reliquary – an object designed to carry materials of religious value.
“We can't say whether or not these bone splinters are from a saint and, if so, which one,” explained Heinzel. “Usually relic packages contain a strip of parchment indicating the name of the saint. In this case, however, we unfortunately can't see one.”
Archaeologists are only aware of three other such reliquaries from this time period.
https://www.iflscience.com/mystery-of-medieval-pendant-full-of-bones-solved-using-neutrons-67148
maximus otter
The ornately decorated pendant was first unearthed in 2008 in the German city of Mainz, in the remnants of a medieval rubbish dump. It was immediately obvious that the pendant had been designed to open like a locket – but, frustratingly, centuries worth of damage meant that revealing its contents would be no easy feat.
The first [technique used] was neutron tomography. Similar to computed tomography (CT) scans that are used in medicine, this is an imaging technique that allows the internal structure of objects to be visualized. When conventional X-rays were not enough to know for sure what was inside the pendant, the restorers used this more advanced method.
The second technique is called prompt gamma-ray activation analysis (PGAA). A beam of neutrons is fired at the object being studied. Some of the neutrons are absorbed by the nuclei of the different chemical elements the object contains, in a process called neutron capture. Almost immediately (hence “prompt”), these new compound nuclei release a burst of gamma rays, which returns the elements to their previous state. The PGAA apparatus measures these gamma rays using a detector made of germanium, so researchers can determine the presence and amounts of different elements in the object.
Neutron tomography and PGAA revealed that there were tiny packages inside the pendant, containing fragments of bone.
The neutron tomography images revealed five packages inside the pendant. Image credit: Burkhard Schillinger, MLZ
Add to this the decorative images of Jesus and other Christian figures that adorn its outer surfaces, and the team suspects that the pendant may have been a reliquary – an object designed to carry materials of religious value.
“We can't say whether or not these bone splinters are from a saint and, if so, which one,” explained Heinzel. “Usually relic packages contain a strip of parchment indicating the name of the saint. In this case, however, we unfortunately can't see one.”
Archaeologists are only aware of three other such reliquaries from this time period.
https://www.iflscience.com/mystery-of-medieval-pendant-full-of-bones-solved-using-neutrons-67148
maximus otter
