Don't know particulars but the ceo up at NRN.v used water for his rock drilling. And James Bay is too far north to pump water very far (more than 200 or 300 feet) in frigid weather so I was told last year. Don't know what additives/cutting fluids are involved. I thought Ian Bliss told me the main deal was keeping the diamonds and bonding material cool and the hole HAS to be flushed -- can't recall gpm needed, but seems like it may be over 60 gpm. Oil well drillers use some sort of water based drilling mud in rock don't they? However it works Jim, it should be very interesting to see what you find out. Thanks, Howard