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Roger Weller, geology instructor            regional geology  planetary  gems

Thomas Fair
Physical geology
Fall 2008


The Making of Arrowheads


Arrowheads can be found through-out most of the United States.  Arrowheads can be made from various materials:  bone, antler, scales, flint, chert, jasper, and quartz. The arrowheads found in some areas are unique because the type of rock or material can not be found in the area for hundreds of miles, so this leads to the belief that the rock used for arrowheads were traded for.  The steps for making arrowheads sounds easy but is a art and takes time and patients to master.

            The rock used for the best arrowheads is flint; this is a sedimentary rock that when it is chipped it forms a very sharp edge.  Flint when chipped leaves a conchoidal fracture, Webster’s defines conchoidal as a “Greek word meaning: like a mussel; or having elevations or depressions shaped like the inside surface of a bivalve shell”.


R.Weller/Cochise College


             Flint is a chemical sedimentary rock made of cryptocrystalline
(very fine-grained) quartz.  It is distinguished from chert by its more shiny surface and its better ability to be chipped into sharp implements such
as arrowheads.


R.Weller/Cochise College


Some of the areas flint can be found is in the Ohio valley, North Carolina, Arkansas, Oklahoma, and Utah.

            Another material used was scales from the gar fish; this was used by the Seminole Indians of Florida.  The gar has heavy ganoid scales.


The Seminoles used these naturally, very hard scales for the heads for their arrows and lances. 

            Obsidian or volcanic glass was also used.


R.Weller/Cochise College


           Obsidian can be found in Yellowstone park region and other volcanic areas.   Obsidian also flakes in a conchoidal fracture making it very sharp.



Obtain the tools you will need to shape your arrowhead. You will need a large piece of antler for shaping large rocks, and a small piece an antler for shaping smaller pieces. The antlers serve as a small hammer, and can be substituted with a hard wood, such as oak, if antler is not readily available. You will also need a hammer stone. This is essentially a blunt stone that is very dense. Granite makes the best hammer stone, but basalt and quartz are also good options.


Find a piece of soft stone that is free from cracks or frost fractures. It should be soft, but not brittle. This will allow you to chip away at the stone in a process known as flaking. The best stone to use is flint. If flint is not indigenous to your area, then chalcedony, chert, jasper, obsidian and quartzite are also good stones to fashion into arrowheads.


Strike your flint, or whichever soft stone you are using, with your hammer stone. Hit the stone hard enough to break off a piece that is small and relatively flat. If the flake that breaks off is already the size of an arrowhead then it is too small. You need a slightly larger piece that you can work down to the proper shape. A flake of flint that is five to six times the size of an arrowhead is ideal.


Use your large antler as a soft hammer to begin reducing the size of the stone. Remember that even though antler works best, a chunk of hard wood, such as oak, will also break flakes off of the stone. Strike the stone with the antler to knock away flakes. The idea here is to make the stone thinner each time. The overall size will also decrease as pieces are chipped away. Grind the hard hammer stone over the edge of the flint each time a flake is broken away. This will grind away any micro-fractures and prevent the stone from crushing on the next blow.


Switch to the smaller antler when the size of the flint begins to be reduced. This will allow you to chip away smaller flake so that you do not ruin the entire arrowhead by knocking off an excessively large flake. Strike the stone with the small antler, and then grind the edge with the hammer stone, until the flint is roughly the right shape and size to be an arrowhead.


Obtain an ishi stick. Traditional ishi sticks were a sturdy stick with a small piece of bone or antler strapped to the tip. Modern ishi sticks can be purchased that are made of hard rubber, with a fine metal tip. Refer to the "Flintknapping Tools" link in the resources section to review a selection of ishi sticks that are commercially available.


Use the ishi stick as a pressure flaker. Hold the flint, now in the rough shape of an arrowhead, in the palm of your hand. Firmly press the ishi stick into the side edge of the flint to break a small flake away. Continue breaking away small flakes all the way around the edge of the arrowhead. This will make the edge thinner than the body of the arrowhead, which makes the stone sharp. You now have a completed stone arrowhead.



Nature Bulletin No. 505-A   November 3, 1973
Forest Preserve District of Cook County
George W. Dunne, President

Roland F. Eisenbeis, Supt. of Conservation