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Re:Meteorite Self-test check-list by toss1 on Friday March 22, 2024 @10:20AM (#39791010)
I read another article which asked strongly that people NOT use rare earth, neodimium or other strong magnets on meteorites, so this should perhaps be emphasized more strongly.

>>You say that your rock attracts a magnet or a compass. Most (>95%) of meteorites (irons and ordinary chondrites) attract cheap magnets because they contain iron-nickel metal. Many terrestrial rocks, however, contain the mineral magnetite, which also attracts a cheap magnet. (Do not use a rare-earth magnet; a cheap “refrigerator magnet” will attract a meteorite.)

The reason is that the strong magnets can re-orient the magnetic properties of the meteorite, ruining it for some aspects of tests or research. Seems polite to not ruin the thing for research for only a few seconds of 'that's cool' sensation.

Re:Meteorite Self-test check-list by kibitzor on Friday March 22, 2024 @05:05PM (#39794859)
To add: there's ongoing research to "reverse-engineer" the magnetic properties of certain meteorites that contain tetrataenite [0], which is as strong as a rare-earth magnet, but requires no rare-earths, but takes millions of years to make[1]. I studied techniques to speed this process up in the lab over a decade ago when this was new, and got to handle meteorites in the process.

A less "magnetically invasive" way to check if a material has magnetic material would be to put a compass nearby (as recommended by the site). Also, one could put a rare earth magnet on a string, watch it align to the earth's field away from the rock in question, then bring it carefully close to the meteorite seeing if it settles to a newer direction. This would still expose the meteorite to a magnet, but a very small field vs checking if something sticks.

[0]https://www.cam.ac.uk/research/news/new-approach-to-cosmic-m... [1]https://en.wikipedia.org/wiki/Tetrataenite

Re:Meteorite Self-test check-list by toss1 on Friday March 22, 2024 @05:26PM (#39795032)
Great extra detail -thx!

Sounds like fun research and a quick skim seems to indicate success in fabrication - congrats! Did you get to the point of making magnets and if so, how strong did they get?