A 2,000-year-old Roman skeleton found in the ancient city of Herculaneum contains glassy remnants from its brain. Scientists studied the shiny samples and discovered evidence of nerve cells. A new study sheds light on how the glass formed.
The glass forms when a liquid, usually molten sand, is cooled quickly. This process can occur naturally, like in sandy deserts, forming lumps of glass called fulgurites. However, the discovery of glassy biological soft tissues had not been found in nature before.
Researchers used differential scanning calorimetry to heat the glassy brain shards and determine the temperature at which they formed. The analysis showed that the brain tissue hit temperatures over 510°C (950°F), suggesting this is where it turned to glass.
The team ruled out the idea that the volcanic ash that entombed Herculaneum was responsible for turning the brain chunks into glass. Instead, they propose that a hotter ash cloud with less intense heat likely affected the young man, allowing for cooling and preservation of the brain tissue. The presence of a skull may have protected against direct contact with the ash cloud, helping to preserve the brain.
Source: https://www.sciencenews.org/article/mount-vesuvius-ancient-brain-glass