Exploration Drilling is the culmination of the mineral exploration process where the third dimension of a prospect, the subsurface geometry, is defined. 

Drilling provides most of the information for the final evaluation of a prospect and will ultimately determine if the prospect is mineable.  Geochemical analyses of the drill samples provide the basis for determining the average grade of the ore deposit.  Careful logging of the drill samples helps delineate the geometry and calculate the volume of ore, and provides important structural details.  The two principle types of drilling are diamond core drilling and reverse circulation drilling (or RVC drilling).