The Mills Ferris wheel jukebox may have used a sapphire needle that
was supposed to last for 100 plays, although in my experience they just
chew up the record with those heavy early electric pickups (which far
outweighed even the Orthophonic reproducers).  Fansteel was a big maker
of these needles; you might try some.

But -- I saw a Mills with a system for changing the needle
automatically after every few plays!  It had a tall transparent
(celluloid?) tube loaded with the usual steel needles, and when the
tone arm came to rest, the mechanism would unclamp the used needle and
feed a new one into place.  That is, if the operator had been to church
and lit several votive candles. :-)  I have no idea how reliable this
system was, but it didn't last long.  I didn't get to see it (try to)
work.

Mike Knudsen