First, understand that some nephrite just doesn't like polish! A
lot depends on how it was slabbed, i.e., where the grain
is...remember nephrite is fiberuous.
I used to spend a loooot of time in the cutting houses in Taiwan
where they were cutting native Taiwan nephrite and later Siberian.
They used chrome oxide on an 8" felt or leather wheel turning at
least 1725RPM. Nephrite, like jadite, likes heat when being polished
so you want to get it pretty hot. If it is dopped, be careful or it
will fly off the stick. If you don't have or don't like chrome oxide,
linde A on a rubber backed loft leather plate will also do a very
For chrysoprase, it is a silica based material (quartz chalcedony)
and the standard is rubber backed soft felt with good grade of cerium
oxide. Run at slow speed (3-400 RPM) and keep the felt just barely
damp. If the felt tries to pull it away from you...it is polishing!
Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2