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The Glass Brain Of Herculaneum

By Evie Rose Grace


Vesuvius from Pompeii ruins 1 (credit: Positano)

In the year 79 CE, Mount Vesuvius erupted, taking around 16,000 human lives. The eruption of 79 destroyed many acres of land, including the settlements of Pompeii and Herculaneum. Herculaneum was first rediscovered in 1709, and Pompeii in 1748. And since then Pompeii is almost constantly being excavated, unfortunately however no more of Herculaneum can be excavated due to the city of Naples being built on top of it, so that now only up to 20% of this historical seaside town has been discovered.

Perhaps one of the most significant excavations of Pompeii was in 1860, when Giuseppe Fiorelli; an Italian archeologist, unearthed the exact shapes of the Pompeii victims. He found spaces, buried under many metres of ash, containing the skeletons of humans, and that were human body shaped. This was due to the ash that piled on top of the dead bodies and then solidified, and then over time the organic matter biodegraded, and only the space was preserved. So Fiorelli dug straight down with a hollowed pole and filled the spaces with plaster, creating exact likenesses of 86 victims; of the currently estimated 2000 people who died in Pompeii, from the 79 eruption, in the moment that they died.

Pompeii plaster fossils 2 (credit: All That's Interesting)

While excavating in Herculaneum, archeologists found many skeletons in the boathouses, and hardly any in the city itself. One body they did find however was lying on a wooden bed, and has been identified as a 25 year old male, and is believed to have been guarding the college.

Photo: College at Herculaneum (credit: Washington Post)

During a recent study of this skeleton, by forensic anthropologist, Pierpaolo Petrone, he discovered pieces of glass that he believed to be the remains of a vitrified (turned to glass) human brain. The scientific proof behind this claim, is that it contained brain protein, and calcium from hair. Another telling factor is that the pieces were found on the inside of the skull.

Glass brain remains (credit: Science Alert)

So what happened?

The eruption lasted around 18 hours, and during this time there were several ‘waves’ of devastating destruction. One of these ‘waves’ is the pyroclastic surge; where clouds of volcanic ash, rocks, and gases move at 700 kmph, and can reach temperatures of up to 1000℃. The scientists and archeologists working on this research believe that during the pyroclastic surge, the victim’s brain was liquified in the immense heat and then when temperatures dropped, was solidified, to become a glassy substance.



  1. Hiser, D. (2020, January 23). Vesuvius eruption baked some people to death-and turned one brain to glass. Retrieved from

  2. Katz, B. (2020, January 23). Vesuvius' Scorching Eruption Turned a Man's Brain Into Glass. Retrieved from


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