Projectile Point FAQ

How Are Points Made?

Stones high in silica (the main component of glass) are hard, somewhat brittle, and have a conchodial (shell-like) fracture pattern.  When one strikes this type of stone at the proper angle and with adequate force, it is possible to remove a flake and create a sharp edge.  By repeatedly removing flakes, one can shape the piece to create the desired form.  Native Americans shaped stone by striking it with either a cobble-like tool called a hammerstone, or with an antler baton.   This technique, which breaks off chips of stone, is known as “percussion flaking.”  The edges of the point, as well as its stem (the portion which is fastened to a wood or bone shaft), may be sharpened and notched by using pressure to remove small flakes.  This second technique, called “pressure flaking,” involved pressing a bone tool against the point to remove flakes.  Native Americans also sometimes ground down the edge or base of the point.  This helped to control the removal of the flakes, and reduced the risk of cutting the sinew that secured the point to the haft.

Heat Treating Stone

Some jaspers and cherts were heat treated by Native Americans.  They used fire to heat and thermally alter a rough stone tool in an attempt to improve its flaking characteristics prior to the final shaping.  Heat treating the stone slowly over a long period of time at approximately 350°C alters the color, luster, and molecular structure of the stone.  The appearance can change in any number of ways, but often the stone becomes darker and/or redder, with a waxier luster.   Heat treating the stone reduces its tensile strength by as much as one-half, thus making it easier to flake.

How Are Points Used?

Native Americans used projectile points as tips on their lances, spears, darts, and arrows, all weapons used primarily for hunting, occasionally fishing, and sometimes combat. When propelled with sufficient force, the sharp tip and edges of a projectile point could penetrate the hide of an animal.  The substantial amount of animal bone found at Native American sites is clear evidence of their hunting prowess and the effectiveness of their weapons.  Some lances, spears, and arrows had a detachable foreshaft, a short piece of wood or bone tipped with a projectile point that fit into the larger wooden shaft.  A foreshaft allowed the hunter to disconnect the shaft once the point on the foreshaft was imbedded in an animal.  Foreshafts also served as knifes. Using a projectile point as a knife, Native American hunters could butcher the carcass of an animal to transport smaller packages of meat back to a village or camp.  Narrow projectile points were used as awls or drills for penetrating hide, wood, bone, and stone.

What Types of Points Are There?

Archaeologists have long recognized that Native Americans made projectile points in different sizes and shapes.  Through careful excavation, they discovered that Native Americans made points of a particular shape at a particular time. Archaeologists figure out how old each of these point styles are by determining the age of the soil deposits in which they were found.  At first, dating tools could not “tell time” with much precision.  With the development of new techniques, such as those that measure the amount of radioactive carbon in organic materials like charred plants or animal bone, archaeologists can determine age within a couple of hundred years.  Thus, they can estimate the age of a projectile point by dating charcoal or bone found in the same deposit.

To sort out the variety of projectile point types, archaeologists name them and assign them to particular cultures or periods of time.  For example, the Clovis point is named for an ancient site found near Clovis, New Mexico in the 1920s.  Based on continuing research, archaeologists have learned that Native Americans made and used Clovis points between 11,200 and 10,800 years ago.

To aid in the identification of projectile points and other artifacts, archaeologists develop reference collections.  A reference collection consists of examples of particular types for comparative purposes.  It is used to identify artifacts consistently to ensure that scientists and laymen can accurately discuss what they have found.