LanthanumK
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Ceramic magnet
I want to find the cheapest source of barium or strontium, in any form. I found that ferrite magnets, the common black brittle magnets, are made of
either strontium or barium ferrite. The question is: Which one is it?
hibernating...
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Arthur Dent
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Pottery grade strontium carbonate is about $9 for 500 g... a heck of a lot more stuff than what you'd get by dissolving magnets and a lot less
complicated. Truly you can't get any cheaper. The Barium Carbonate at that Pottery store I go to is 8$ for half a kilo.
Robert
--- Art is making something out of nothing and selling it. - Frank Zappa ---
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LanthanumK
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I actually am making an economy element collection, not extracting the chemicals (although I've done that already). I want to know whether I can
regard the magnet as strontium, barium, or whichever I feel like placing it in.
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hkparker
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If you want an element collection wouldn't you want the pure element? Take some strontium or barium salt, convert it to its oxide, and thermite it.
My YouTube Channel
"Nothing is too wonderful to be true if it be consistent with the laws of nature." -Michael Faraday
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LanthanumK
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Is is hard to do a thermite reaction without strontium or barium salts, crucible, blowtorch, magnesium ribbon, laissez-faire parents, etc. 
When I say economy element collection, I mean an *economy* element collection, where arsenic is in the form of an AlGaAs infrared LED from an old
remote control, and cerium is in the form of mischmetal from a cigarette lighter picked up off the road.
For this topic, Google has been surprisingly silent. But I did find a source that mentions just strontium.
hibernating...
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Neil
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I have a feeling that this is self defeating. How can anyone give you an answer? I have red socks and blue socks, which color am I wearing?
If you hunt down a specific magnet brand and then set out to find what it's made of you would be able to find out which one it is, ether by MSDS,
product knowledge or testing.
And if a budget collection is what you seek, then the carbonates seem to be about as budget as you can get.
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Endo
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Good source of Strontium nitrate: Buy a road flare.
http://www.orionsignals.com/safetydata/fuseehighway.pdf
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Neil
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https://www2.itap.purdue.edu/msds/docs/3512.pdf
https://www2.itap.purdue.edu/msds/docs/3549.pdf
http://www.magxamerica.com/msds.pdf
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condennnsa
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From wikipedia:
"Ferrites are produced by heating an intimate mixture of powdered precursors pressed into a mold. During the heating process, calcination of
carbonates occurs:
MCO3 → MO + CO2
The oxides of barium and strontium are typically supplied as their carbonates, BaCO3 or SrCO3. The resulting mixture of oxides undergoes sintering.
Sintering is a high temperature process similar to the firing of ceramic ware.
Afterwards, the cooled product is milled to particles smaller than 2 µm, small enough that each particle consists of a single magnetic domain. Next
the powder is pressed into a shape, dried, and re-sintered. The shaping may be performed in an external magnetic field, in order to achieve a
preferred orientation of the particles (anisotropy).
"
I have also thought about this some time ago, as I have a lot of badly demagnetized loudspeaker magnets. Since then I bought a kilo of Barium
Carbonate, so that solved my need of barium salts. But I still don't have strontium.
If I remember correctly, of the two types of barium and strontium ferrite magnets, the strontium ones are the majority and cheaper.
It might be possible to identify which one a magnet is by a flame test.
Barium should give a green flame, and strontium a red flame.
From the same wiki article:
"
Strontium ferrite, SrFe12O19 (SrO·6Fe2O3), a common material for permanent magnet applications.
Barium ferrite, BaFe12O19 (BaO·6Fe2O3), a common material for permanent magnet applications. Barium ferrites are robust ceramics that are generally
stable to moisture and corrosion-resistant. They are used in e.g. subwoofer magnets and as a medium for magnetic recording, e.g. on magnetic stripe
cards. "
So with 6 parts fe2o3, the yield won't be great, but it's worth trying. Perhaps other members can advise as to what would be the best acid for
dissolving these magnets.
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LanthanumK
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Endo: It appears that it is quite difficult to extract Sr salts from road flares, although I could just use the entire road flare: http://www.spiegl.org/rocket/flare/flare.html. It seems that you need to get flares in packs, minimum 36 flares or something like that. This would
be a waste of extra flares.
Neil: From what you said, Sr ferrite magnets are more common. So I am classifying my magnet as containing Sr and a magnetic stripe card as containing
Ba.
Condennnsa: You can see that Wikipedia is very ambiguous on which one (Sr or Ba) they use. That is why I tried asking around.
Thanks for your help everyone. Next time it may be semiconductors in LEDs. 
hibernating...
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condennnsa
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Well the ferrite article on wiki does say that strontium ferrite is a common magnetic material. Even if you look around online you'll see that most
references are for sr ferrite. This makes me pretty certain that 95%+ of ferrite magnets are Sr.
My understanding is that Ba ferrite is used where it's important to be resilient to corrosion.
An easy way to separate either Barium, or Strontium after successfully dissolving the magnets I guess would be to precipitate the sulfate with Na2SO4,
or FeSO4 . Both SrSO4 and BaSO4 are insoluble in water, especially barium.
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unionised
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I wonder if the densities of the two ferrites are measurable different
I also wonder if they use a mixture.
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