Turning MICA

You must jest. I don't think you can turn Mica with a normal tool.

You might get away with it by sanding.

You are talking stone and it is hard material and thin layers.

The basic material is AlSi3O10 with other KAL2(OH)2 tacked on.

So you are basically cutting an Aluminum oxide material.

They make sand paper with that material. Then another Aluminum oxide within the matrix.

Carbide is the cutting tool. High speed steel will be cut or dulled rapidly. Carbide uses pressure to cut and not a sharp edge - so it isn't what is needed.

Use a Garnet sandpaper - Garnet will likely cut it. You might have to get green paper boron...

Likely the method - spin it on the lathe and use a Dremel with a green wheel.

Martin

"Martin H. Eastburn" wrote in news:JetOk.228046$ snipped-for-privacy@en-nntp-07.dc.easynews.com:

Actually, when discussing hardness, in many cases the arrangement of the atoms in the mineral's molecules is just as important, or maybe more so, than the chemical composition of the mineral. A good example is the difference in hardness between diamond, the hardest mineral, and graphite, the softest. Both are pure carbon, just difference atomica arangements.

The Mohs hardness of mica is between 2.5 and 3, pretty soft, whereas aluminum oxide sandpaper has a Mohs hardness of around 9, so sanding seems to me to be entirely appropriate. However, how are you going to keep the mica from flaking to bits? I assume you either have pieces of whole crystals which cleave into extremely thin flakes (like in your old toaster), or you have some kind of mica composite, with shiny mica flakes in a binder of some kind, say, epoxy or polyester resin.

Seems like sanding is the way to go, as edged tools would catch on the mica flake edges no matter what the composition.