What is the best way to mount white mica separates?

Question

I have detrital mica separates that I would like to mount in EpoThin resin for microprobe analysis and I would simply like to know the best method for mounting them. With zircons you can mount on double sided tape and then simply pour the resin over them. But with micas I am worried that they will not peel away easily from the tape once the resin has cured. I am also concerned about polishing them. Any advice would be much appreciated.

Answer 1

Hi Asked,

Something you would need to consider is, what is the particle shape of these mica samples? Is it fairly flat plates? If so, you should be able to just dust them down on the tape, maybe brush gently to turn them flat on the surface.

Flat plate mica etc. is commonly used in cosmetics as pearlescent products. The platy material aligns on a surface (e.g., skin) just fine with the shear of application, in a vehicle. I don't think the tape adhesive could compete with the resin bond. But, if you needed to, you might reduce the tape adhesion by something as simple as chilling the tape + support, then breathing down on it, before dusting the sample on. That would put a film of water on, which should be labile, perhaps, without interfering with the resin bonding. A little pretesting would go a long way!

Why the polishing? Physically, the mica should be crystalline and planar already, and if it isn't, polishing would be as likely to tear up the surface as to smooth it?

-- Cheers, -- Mr. d.