FMF - Friends of Minerals Forum, discussion and message board

[Adi_Lev]

I have some Zambian emerald specimens covered with Biotite (?) Mica
I want to remove / clean / get read of the mica.

I tried many mechanical options, picking , scrapping, drilling ultrasound , all were not satisfactory.
I would like to try chemistry to clean / remove / dissolve the mica. I know this is hazardous and I will not do it myself, I have a friend who is a professional chemist and he will do it for me at his lab.
I know some prefer not to remove the mica, but i feel it is best for the minerals that I have
as it will allow me to sort out cuttable material without destroying the crystal

Thanks

Adi

[Jesse Fisher]

To my experience, micas are fairly resistant to most chemical treatments, including HF. Mechanical removal with an air abrasive and a hard abrasive powder is perhaps the best option.

[Adi_Lev]

Thank you
Adi

[Joseph DOliveira]

I regularly use a small bench sand blaster with glass beads to remove mica and other attached mineral coatings from other hard mineral specimens. As long as the hardness is greater than 5 it should work without doing any damage or causing any fogging.

Good luck.

[Adi_Lev]

Thank you
Adi