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I have very small mineral samples, and I'm looking for a glue that can hold them through a sample preparation process that I'm doing: heating, polishing, and measuring magnetic moment. For that I want the glue to have 3 criteria:

  • heat resistant (over 600 Celsius)
  • can hold through polishing (therefore can't dissolve in water)
  • very important: that it won't acquire magnetic moment after being in an external field, since I want to measure very weak magnetic moment from my samples.

I tried AREMCO Ceramabond 569. My measurements showed that it does acquire a magnetic moment when exposed to an external magnetic field (it was recommended by the company).

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    $\begingroup$ not many companies are going to test their epoxies for magnetic properties you may just have to experiment. You might try embedding them in glass. $\endgroup$ – John Oct 25 '17 at 15:07
  • $\begingroup$ It would be helpful if you could add some quantitative detail: how big are your samples? How magnetic are they? What's the maximum remanence you can accept for the glue? $\endgroup$ – Pont Oct 25 '17 at 16:02
  • $\begingroup$ @John To embed in glass you have to melt the glass, which will presumably heat the sample enough to erase the magnetism that Galya's trying to measure. $\endgroup$ – Pont Oct 25 '17 at 16:20
  • $\begingroup$ @Pont without knowing the mineral I couldn't say, I have has success with it in paleontological samples, but we were not looking for magnetics we just had an issue with metal contaminants, but embedding the sample may be the answer, there are a far larger variety of castable solids than adhesives, even furnace mortar or fireable clay may work. $\endgroup$ – John Oct 26 '17 at 3:22
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Your question is quite similar to one that I asked some time ago, with the additional requirement that the glue be insoluble in water, which unfortunately excludes sodium and potassium silicate. Like you, I've found Ceramabond (albeit 571, not 569, in my case) to be too magnetic. I suspect that there's an element of random variation here. It's not (as far as I know) specifically formulated to be completely non-magnetic, so there may be some batches which are more magnetic than others. Khakhalova and Feinberg (2014) investigated some other high-temperature ceramic adhesives and found that they were also too magnetic for use with weakly magnetic samples. However, they do make one useful suggestion:

It may be possible for rock and paleomagnetic labs to reduce the concentration of magnetic contamination in Omega cements, for example, by sending the powder through a very clean Franz magnetic separator multiple times.

I haven't yet heard of anyone actually doing this, but it certainly seems worth trying. They also write that

We’ve contacted Omega Engineering Inc. regarding the iron concentrations in their cements and their technical staff are currently exploring whether it would be possible to produce a high purity, high temperature cement specifically for rock magnetic and paleomagnetic applications.

I don't know if anything has come of those attempts in the three years since the article was published, but you could email the authors and/or Omega to find out.


References

Khakhalova, Evgeniya and Feinberg, Josh M. (2014). The iron that binds: The unexpectedly strong magnetism of high-temperature ceramic cements commonly used in rock magnetic experiments. IRM Quarterly, 24(2), url: http://www.irm.umn.edu/quarterly/irmq24-2.pdf

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