Flint is a common sedimentary rock often found in large limestone deposits around the world. This particular stone has been used for thousands of years for making hand tools and projectile points such as knives, spear tips and arrowheads. Native Americans often used flint, obsidian and chert to form arrowheads through a process known as flint-knapping. This process is otherwise referred to as pressure flaking, and is essentially the art of carving an arrowhead. This process can still be performed using traditional methods.
Locate a piece of flint that already has a flat shape. This will make the knapping process easier, as less material needs to be removed.
Fold a piece of rawhide over your non-dominant hand. Place the flint in the rawhide. This will help protect your hand from the knapping process.
Strike lightly along the flint's edge with a round river rock (hammer stone), working from top to bottom. Strike the same way along the edge each time to flake the rock consistently. Repeat the process on both sides until you form a rough triangle shape.
Flip the stone over and repeat using another sharpened piece of bone. Press hard against the flint and push away from the stone's edge. This will hone the flint and create a sharp edge.
File two 1/4-inch notches on both sides of the triangle base using a sharp, coarse rock. This will form the arrowhead base, and will be used to attach the arrowhead to the shaft.
Rub a flat piece of smooth flint over both sides of the arrowhead surface, excluding the edges. This will help to polish the flint and remove any burrs, bumps or rough spots.
Try this same process using obsidian. Obsidian can be made razor sharp, and is still used today on some surgical scalpels.
Use caution when handling sharp flint. The flakes can easily lacerate the skin.