Hi Mark, > Ok, I gots a pondering problem. And I'd like some feedback. > I've tried to etch some irons I have, to no avail, yet. I > would like to know if anyone has etched their own, and how > polished are the slices?
So far I've played around with etching Campo, Gibeon, Chinga and various iron fragments that upon etching revealed themselves to be manmade (i.e. no W-pattern). I've never tried etching with Nitol; just ferric chloride (which is much faster acting). I would think that with octahedrites, even a polish to 800 or perhaps even 600 grit would be sufficient to see a pattern, but of course it looks better when polished to 1500 or 2000. > I've tried one I recieved that was polished very brightly, > and it is now just dull. So, I was also working on another > myself and ground it flat, then put it to the 1200 grit > and tried to etch it, but got nothing (it did look better > than the piece I had bought already polished though). Was it an octahedrite? I assume you're looking for a Widmanstaaten pattern and not Neumann lines. The latter are much more subtle (I've learned from recent experience). Whereast ferric chloride will etch an octahedrite nicely in only a few seconds, it took nearly a minute to really see the Neumann lines in a specimen I recently acquired. > I'm just about ready to say maybe my nital isn't of the > correct concentration, but before I dump it into the > waste bottle I like to hear some insight from others. Guess it depends on how long you were soaking in it -- Nitol is pretty slow I understand. Cheers, Rob ______________________________________________ Meteorite-list mailing list [EMAIL PROTECTED] http://www.pairlist.net/mailman/listinfo/meteorite-list
