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Thanks, this was the sentence that was missing from the article and made me confused knowing that humans are basically made of carbon, but glass is not.

by unwind 2y ago

Someone 2y ago
The article should have said “a glass”, not “glass”. The former is a term from physics that is different from the lay-mans’s “glass”. https://en.wikipedia.org/wiki/Glass_transition https://en.wikipedia.org/wiki/Glass_transition: “The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass.” The Nature article is clearer. https://www.nature.com/articles/s41598-025-88894-5 https://www.nature.com/articles/s41598-025-88894-5: “Glass forms when a liquid is fast cooled preventing crystallization, across a reversible process known as the glass transition. […] Here we demonstrate that material with glassy appearance found within the skull of a seemingly male human body entombed within the hot pyroclastic flow deposits of the 79 CE Vesuvius eruption formed by a unique process of vitrification of his brain at very high temperature” The layman’s term includes such things as safety glass, which may have polymer layers. So, confusingly, not all glass is “a glass”, and not all glasses are glass.
kergonath 2y ago
> humans are basically made of carbon, but glass is not A glass is something that underwent a glass transition (that looks like a liquid at the atomic scale but behaves like a solid microscopically, resulting from cooling a liquid too fast to let it crystallise). It can be made of a huge diversity of things: pure elements (like carbon or sulphur), some metallic alloys, oxides, sulphides, fluorides, polymers, etc.
- gpvos 2y ago
  But the article says "glass", not "a glass".
  - kergonath 2y ago
    Using “glass” as a strict equivalent for “silicate glass” is incorrect. Metallic glass is glass. Not the glass you are used to, but still glass.
    - gpvos 2y ago
      I'm not convinced that that is common usage. Maybe in technical circles.
kazinator 2y ago
However, I've not been able to find much on carbon-oxgen based glass. It's possible to make glass out of CO2 gas, under high pressure. However, at standard pressure, the glass boils off into CO2. There are definitely some unconnected dots in the story. I have a sense that what is needed is to reproduce this allegedly vitrefied organic material in the lab. Could this actually be more like a plastic? Some thermoplastics share characteristics with the category of glass, like having amorphous structure and a gradual softening resembling glass transition temperature. Conversely, we could say that glass, such as a common silica glass, is a kind of thermoplastic. In: https://en.wikipedia.org/wiki/Thermoplastic https://en.wikipedia.org/wiki/Thermoplastic we have language like "[a]bove its glass transition temperature and below its melting point, the physical properties of a thermoplastic change drastically without an associated phase change." Also: https://en.wikipedia.org/wiki/Glass#Polymers https://en.wikipedia.org/wiki/Glass#Polymers "Many polymer thermoplastics familiar to everyday use are glasses." https://en.wikipedia.org/wiki/Glass#Non-silicate_glasses https://en.wikipedia.org/wiki/Glass#Non-silicate_glasses "Besides common silica-based glasses many other inorganic and organic materials may also form glasses, including [...] nitrates, carbonates, plastics, acrylic, and many other substances."

Thanks, this was the sentence that was missing from the article and made me confused knowing that humans are basically made of carbon, but glass is not.

by unwind 2y ago

Thanks, this was the sentence that was missing from the article and made me confused knowing that humans are basically made of carbon, but glass is not.

Someone 2y ago

The article should have said “a glass”, not “glass”. The former is a term from physics that is different from the lay-mans’s “glass”. https://en.wikipedia.org/wiki/Glass_transition https://en.wikipedia.org/wiki/Glass_transition: “The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass.” The Nature article is clearer. https://www.nature.com/articles/s41598-025-88894-5 https://www.nature.com/articles/s41598-025-88894-5: “Glass forms when a liquid is fast cooled preventing crystallization, across a reversible process known as the glass transition. […] Here we demonstrate that material with glassy appearance found within the skull of a seemingly male human body entombed within the hot pyroclastic flow deposits of the 79 CE Vesuvius eruption formed by a unique process of vitrification of his brain at very high temperature” The layman’s term includes such things as safety glass, which may have polymer layers. So, confusingly, not all glass is “a glass”, and not all glasses are glass.

kergonath 2y ago

> humans are basically made of carbon, but glass is not A glass is something that underwent a glass transition (that looks like a liquid at the atomic scale but behaves like a solid microscopically, resulting from cooling a liquid too fast to let it crystallise). It can be made of a huge diversity of things: pure elements (like carbon or sulphur), some metallic alloys, oxides, sulphides, fluorides, polymers, etc.

gpvos 2y ago
But the article says "glass", not "a glass".
- kergonath 2y ago
  Using “glass” as a strict equivalent for “silicate glass” is incorrect. Metallic glass is glass. Not the glass you are used to, but still glass.
  - gpvos 2y ago
    I'm not convinced that that is common usage. Maybe in technical circles.

kazinator 2y ago

However, I've not been able to find much on carbon-oxgen based glass. It's possible to make glass out of CO2 gas, under high pressure. However, at standard pressure, the glass boils off into CO2. There are definitely some unconnected dots in the story. I have a sense that what is needed is to reproduce this allegedly vitrefied organic material in the lab. Could this actually be more like a plastic? Some thermoplastics share characteristics with the category of glass, like having amorphous structure and a gradual softening resembling glass transition temperature. Conversely, we could say that glass, such as a common silica glass, is a kind of thermoplastic. In: https://en.wikipedia.org/wiki/Thermoplastic https://en.wikipedia.org/wiki/Thermoplastic we have language like "[a]bove its glass transition temperature and below its melting point, the physical properties of a thermoplastic change drastically without an associated phase change." Also: https://en.wikipedia.org/wiki/Glass#Polymers https://en.wikipedia.org/wiki/Glass#Polymers "Many polymer thermoplastics familiar to everyday use are glasses." https://en.wikipedia.org/wiki/Glass#Non-silicate_glasses https://en.wikipedia.org/wiki/Glass#Non-silicate_glasses "Besides common silica-based glasses many other inorganic and organic materials may also form glasses, including [...] nitrates, carbonates, plastics, acrylic, and many other substances."