Hi Al, (et Al)
My MFA thesis involved titanium, back in the bad old days before
Bill came up with multi-etch. So I’ve used HF.
Have absolutely no interest in ever getting within 50 feet of it
again. Been there, done that, have the degree, and all my fingers. I
call that a win.
My goal was to etch away the granite, so I could see what the
crystal structure is at the rear of the deposit face, where it
hasn’t been blown apart by dynamite.
(And to see what the micro crystals really are.)
It really is garnet, and it really does ‘cleave’. It’s a very
oddball deposit, one of only 2-3 in the world. There’s a reason I
flew half way around the world, drove several hours, then bushwacked
to the top of a mountain in the back of beyond to go get these
things. The garnet body is shot through with planes of ?mica? that
act like the sheets of paper in a stack of sliced cheese.
So it doesn’t ‘cleave’ like a diamond, but you can break it out into
flat(ish) slabs. Not flat enough, it turns out, and certainly not
easily, but I’ve got enough material to test with, which was the
The ultimate goal was/is to figure out the nature of the stone
cutting for migration period garnet jewelry. How’d they get all
those flat slabs? Before you say “a lap”, please remember that the
first surface plate wouldn’t be made for another thousand years. And
the garnets are FLAT. Some of them to within angstroms. So how’d
they make flat garnets with no flat reference surface? With no
abrasives harder than garnet itself, and no substrate to lap on
that was any harder than the garnets. The garnet powder would be
chewing up the lap faster than the garnets, and the stones
themselves show no trace of rounding from a chewed up lap. So what’d
That one had been bugging me for a couple of years, but I finally
figured out a way to do it that they could have easily done in
period, that doesn’t require a reference flat, or any fancy tools.
It’s almost automatic, once you get the basic rig built. (Details
forthcoming once I get them published officially, or find out that
it’s a bad idea.)
Thanks for the help. I was hoping somebody had an ace up their
sleeve that I didn’t know about.