Obsidian

["GeorgeJulieJessie Graham" <gjjgraham@xxxxxxxxxxx>]

Arthur,

I thought I'd weigh in on this subject.
Obsidion is volcanic glass, so its chacteristics are the same. Its pure
silicone, so wearing a good dust mask is wery important. Its very brittle,
which is why prehistoric  people made arrowheads and other cutting tool out
of it. It was worked the same way flint and chert were "knapped" into tools.
Flaking it into usable pieces. The large ceremonial knives found in mexico
show a skill and knowledge of obsidian that is amazing.

Carving this stuff today is not such a big deal. Diamond and carbide burrs
and wheels that go with a die grinder will cut and grind it away. I also
agree with a previous reply to your question that recomends sandblasting.
You don't need much pressure to work down glass of anykind. Its a lot of fun
to carve with a small sandblaster, BUT, Dust is a BIG problem. The finish
you are left with will be frosted, so to get a polished finish will take
some sanding with carbide or diamond paper.

It can be done and a finished piece of sculptured obsidian sounds great.

Get a Good Dust Mask!!
Good luck
George Graham