Rock Core Drilling techniques use a diamond-tipped core-saw a string of drill rod. The cored rock is captured inside of the core-saw and is removed from the hole during each interval. This is used only in the case of relatively hard geologic formational material and is not effective in almost any other condition. Casing is placed behind the cores. Driven samples or drive counts can be advanced from the bottom of the hole if the rock is not too hard, and temporary or permanent wells can be set. Circulated water is used as in the mud-rotary drilling technique to keep the saw from overheating.
