Drilling round, triangle, and star holes in Granite.

Sonically drilling geometrics in stone. Jeffrey Appling GJG (GIA) I used to think power came from great explosions (an outward force full of fire). Explosions pushing pistons, bullets and grenades blasting out projectiles at high velocities, high speed rotating diamond drills, giant bulldozers, and red hot rocket fuel to the Moon, right? ….. Wrong! Completely … More Drilling round, triangle, and star holes in Granite.