Mount Vesuvius turned this ancient brain into glass THE ONLY OCCURENCE ON EARTH!
The eruption of Mount Vesuvius 79 AD is most famous for entombing the whole roman city of Pompeii. Nearby, Herculaneum, which was also buried in the eruption, had the preserved skeleton of a young man lying in his wooden bed, found to have remnants of his brain made of glass. This is the only such occurrence on Earth.
Glass forms when a liquid is fast cooled preventing crystallization, across a reversible process known as the glass transition. Organic tissues are commonly preserved as glass by processes of vitrification at very low temperatures and can return to their original soft state when heated back to ambient temperature. It would therefore be impossible to find organic glass embedded in volcanic deposits that have reached several hundred of Celsius degrees.
Calorimetric analyses show that the temperature at which the brain transformed into glass was well above 510 °C, implying that the body was exposed to the passage and vanishing of a short-lived, very hot pyroclastic flow (volcanic matter and gas), therefore having an early fast heating followed by a very fast cooling. The glass that formed as a result of such a unique process attained a perfect state of preservation of the brain and its microstructures.
Samples from ancient brains are sparse, and they are normally soap like or mummified, so this brain where you could observe tubular structures, cell bodies, neurons, myelin layers etc, is described to be “something really astonishing and incredible,”.
