Granite is an igneous rock.
A formation may be porous yet impermeable if there is an absence of connecting passages between the voids within it. See permeability . It is made up of drill pipe or tubing at the surface, run into a well, and set down on the object that has been lost in the well. The block is retrieved and the impression is examined. The impression is a mirror image of the top of the fish and indicates the fish's position in the hole, i.e., whether it is centered or off to one side.