I have spent many years in New Zealand cutting hard stone and
nephrite jade in a variety of diamond saws ranging in size from 6 to
36 inch blades.
A commonly used coolant/lubricant over here has been used transformer
oil which we were able to get at about 10cents a gallon. As you are
probably aware there are two types of this oil, one is quite toxic
and should not be used, the other which is used over here for the
large outdoor electric power transformers has never given any
trouble , is quite bland and performs well.
We have been able to get this material from Electric power boards
when they have changed the oil in their transformers for what-ever
For nephrite jade using drop-arm saws we use only water as this is
quite adequate. Oil of any sort is not a good option is it gets into
cracks in the stone and conceals them.
Keith Torckler New Zealand