"Studying these layered strata is known as magnetostratigraphy and can be used to verify radioactive dating methods. Geologists used magnetostratigraphy to cross-check the dates of the Nakali Formation, where Nakalipithecus nakayamai’s jaw was found."
Because the location of the pole is constantly shifting, the TRM of ancient pottery points in a slightly different direction than that of pottery made today.
Did anyone else have a strong "WTF?" reaction upon reading that sentence? Yes, the pole has moved. No, it's completely irrelevant given that not every piece of pottery even manufactured at the same time is going to be fired in the exact same orientation relative to the pole.
The researchers determined that any sample older than a millennium had to be heated to at least 234 degrees Fahrenheit before its VRM was erased. New pottery samples’ VRMs, meanwhile, could be wiped at lower temperatures.
What prevents forgers from generating such magnetic fields? That might be worth while if people start to blindly believing that "pottery frozen magnetic fields are not possible to counterfeit". Note that "not possible to counterfeit" is not a claim in the article.
https://impacts.to/downloads/lowres/impacts.pdf#page=23
Quoting my book:
"Studying these layered strata is known as magnetostratigraphy and can be used to verify radioactive dating methods. Geologists used magnetostratigraphy to cross-check the dates of the Nakali Formation, where Nakalipithecus nakayamai’s jaw was found."
Because the location of the pole is constantly shifting, the TRM of ancient pottery points in a slightly different direction than that of pottery made today.
Did anyone else have a strong "WTF?" reaction upon reading that sentence? Yes, the pole has moved. No, it's completely irrelevant given that not every piece of pottery even manufactured at the same time is going to be fired in the exact same orientation relative to the pole.
The researchers determined that any sample older than a millennium had to be heated to at least 234 degrees Fahrenheit before its VRM was erased. New pottery samples’ VRMs, meanwhile, could be wiped at lower temperatures.
That's a more useful difference which I would attribute to the ceramics having different Curie points in their compositions, and of course it's not something too difficult to change: https://en.wikipedia.org/wiki/Curie_temperature#Changing_a_m...
Incidentally, this effect of temperature on magnetism is how the https://en.wikipedia.org/wiki/Magneto-optical_drive media records data.
What prevents forgers from generating such magnetic fields? That might be worth while if people start to blindly believing that "pottery frozen magnetic fields are not possible to counterfeit". Note that "not possible to counterfeit" is not a claim in the article.
The method of seems to involve hearing the artifacts which seems plausibly risky for an ancient artifact.
can this clue be circumvented by using magnets oriented in a certain way around the workshop while constructing the pottery?