The needle is struck out from the iron (originally a stone) and the nature of mother and son is that ... Chinese scholars had devised a way to magnetize iron needles, by rubbing them with magnetite, ...

To make that call, you need to look in on the process [IllyriaD] used to collect magnetite sand and turn it into a wicked-looking chef’s knife. This began by collecting 150 pounds ...

More information: Zhiyong Lin et al, Methanogenic Archaea as Catalysts for Magnetite Formation in Iron‐Rich Marine Sediments, Journal of Geophysical Research: Solid Earth (2024). DOI: 10.1029 ...