On Thursday, November 16, 2017 at 4:39:48 PM UTC-8, Bob La Londe wrote:
"Ed Huntress" wrote in message

See if you can get a small piece of Macor, a machineable glass
ceramic.

Wow! The stuff sure is expensive.

Yeah; soapstone, slate, pyrophyllite, and other natural products are also
machinable, and cheap as rocks.

I'd go with glass, even if I had to visit the crafts store and buy a sixpack of round
mirrors and desilver 'em in lye. Or take a diamond blade to a Tabasco bottle.