"The glass formed as a result of this process allowed for an integral preservation of the biological brain material and its microstructures," said forensic anthropologist Pier Paolo Petrone of Universita di Napoli Federico II, one of the study's lead researchers.
The glass was formed by vitrification, the process of transforming a substance into glass, when the brain's organic material was exposed to the incredibly high temperatures - at least 510C (950F) - before rapidly cooling.
"Taking one of these fragments, it had a black appearance and shiny surfaces quite similar to obsidian, a natural glass of volcanic origin - black and shiny, whose formation is due to the very rapid cooling of the lava.
Along with Pompeii, the ancient settlement was obliterated in 79AD when the volcano erupted, killing thousands and burying both under a thick layer of volcanic material and mud - preserving them in excellent condition for future archaeologists.
He added: "The only other type of organic glass we have evidence of is that produced in some rare cases of vitrification of wood, sporadic cases of which have been found at Herculaneum and Pompeii.
