Gemstone magnetism

After reading the thread regarding olivine https://www.prospectingaustralia.com/forum/viewtopic.php?id=26575 I started to wonder weather the peridot I had cut was glass sold as peridot rough because it's a very greenstone without a tinge. (although I was fairly sure from memory the rough contained 'Lilly pads'). I wasn't going to do a scratch test.
Anyway I came across the vid. Pretty cool and my peridot is probably peridot.

[video=480,360]https://youtu.be/U9pM04cY7sU[/video]

The magnet I used was a lot smaller (pick-up tool)

This website gives a lot of info also.

https://www.gemstonemagnetism.com/

Very interesting, with modern synthetics we need all the advantages we can get.

Very interesting demo there MM.

Ive tried to get iron alumuminium garnets to attract to a magnet before without success. The flaoting on water to is somethj g i hadnt thoight of.

Spinels are commonly quite magnetic. Also, Some gems are magnetic because of small inclusions of magnetite, rather than the gem itself being magnetic. The following list includes a few relevant minerals:

https://www.911metallurgist.com/blog/electromagnetic-separation-by-minerals

Lefty said:

Very interesting demo there MM.

Ive tried to get iron alumuminium garnets to attract to a magnet before without success. The flaoting on water to is somethj g i hadnt thoight of.

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Yep! Same here, tried it and got no response. That's why I put the vid up. I think I may try and chase down a 13mm N52 magnet so I can compare apples with apples. The magnet I'm using can't pick the peridot up but can 'rock' it with my small magnet. Same goes for my supposed Spessartine garnet. So with the right magnet it should pick up.

Keen Ken said:

Very interesting, with modern synthetics we need all the advantages we can get.

Click to expand...

This table would help. https://www.gemstonemagnetism.com/magnetic_index.html
Note the synthetic sapphire gives the same result as a metamorphic saph. My saph from lava plains gave a weak response even though they are the typical dark bottle blue colour.