Channel flakes are the single flakes that were removed during Stage 6 and Stage 9. Their scars are the flutes on each face of the Folsom point. Unlike the other byproducts (flakes) of manufacture, channel flakes are diagnostic of Folsom. They are as diagnostic as the preform or the finished point.
A channel flake is a long, thin, narrow flake; length--40 mm1, width--15 mm, and thickness--1.9 mm (Wilmsen and Roberts 1978:100). It is obviously unifacial. Its most diagnostic characteristic is the flake scar pattern on the dorsal face which resulted from the controlled pressure shaping of the preform during Stages 4 or Stage 7. These scars are oriented perpendicular to the long axis of the channel flake and terminate at the center of the dorsal face. They originated from beyond the lateral edges.
Channel flakes are never found intact and very seldom are all fragments of a single flake recovered. I have never seen an intact one nor all the fragments to a whole one. Several knappers have told me that most of the time the channel flakes they produce come off in pieces during the fluting process. I speculate that one of the reasons they break on creation or shortly thereafter is that they are so thin. The general consensus is they are usually broken into three (3) or more fragments.
The examples of channel flakes shown on this page were partly selected for their photogenic qualities. As a result, five (5) of the six (6) examples are jasper. Additionally, they tend to be slightly larger than the average dimensions presented above .
Cotterell and Kamminga (1987) identified three (3) types of flake initiations in their paper The Formation of Flakes. Channel flakes were produced by two of these initiations; Hertzian Cone and Bending. These two initiations produce very different results. The cone initiation produces a larger flake (greater mass) than the bending initiation for the same size striking platform2. My data indicate that 60% of the channel flakes in the archaeological record are cone initiations and 40% are bending. They also show that 75% of the preforms failed during the removal of a cone initiated channel flake. (Successfully fluted preforms and finished points have their proximal end reworked so the type of initiation cannot be determined.) Based on this information, I believe the Folsom knappers were doing everything possible to remove a channel flake with a bending initiation. This statement applies even more for the fluting of Face B since the preform was thinner and more delicate at that time. One way to encourage a bending initiation is to cause the angle of blow to be greater than 90 degrees (Pelcin 1998). Still, causing a bending initiation was not automatic because chance still plays a large role.
This is a proximal fragment of a channel flake made from a red jasper. The indented right, distal edge in the left image has been used or worked. The flake scar pattern on the dorsal face (left image) places this artifact in the group identified by Wilmsen and Roberts (1978:101) as "characterized solely by scars that are laterally oriented across the dorsal face." At the Lindenmeier Site, this group represented 85% of the channel flakes. Measurements on this channel flake are 18.4 mm (est.) wide and 1.8 mm thick.
This is a proximal fragment of a channel flake made from a brown jasper. The left lateral edge in the left image has been backed (very fine work) to enable the flake to be held with the finger on this edge. The right edge was then used for cutting. The channel flake belongs in Wilmsen and Roberts' other category that "display longitudinally directed scars superimposed upon the lateral pattern on the proximal ends." This group represents the other 15% of the channel flakes. Measurements for this channel flake are 14.7 mm wide and 2.1 mm thick.
This is a proximal fragment of a channel flake made from Lake Valley chert. Notice how much larger the platform is compared to the two cone initiations above. Also, note the "lip" at the intersection of the ventral face and the striking platfrom (right image). The larger platform "lip", and the "necking" just above the platform, are characteristics of a bending initiation. This channel flake belongs in Wilmsen and Roberts' "longitudinally directed scars" category. Measurements are 16.1 mm wide and 2.1 mm thick.
This is a proximal fragment of a channel flake made from a brown jasper. It belongs to Wilmsen and Roberts' "laterally oriented" category. This channel flake is also the best example of an extremely polished (ground) striking platform. I know the reader can't see this polish in the image so you will have to take my word that this platform has had all the facets completely obliterated. (Return to Stage 8 for more information on platform polishing.) Measurements are 16.8 mm wide and 1.7 mm thick.
This is a midsection fragment of a channel flake made from brown jasper. It is an unusually large artifact. Conceivably, it could have been twice as long as it is here. It is made of four fragments that are glued together. Notice the most distal fragment (top in images) is a different color. This piece was in a different environment from the other three (3) after they were separated. Possibly it was in a fire. Measurements are 21.3 mm wide and 2.7 mm thick.
This is a midsection fragment of a channel flake made from brown jasper. It consists of two pieces that were found approximately 200 meters apart. For many years they laid separated in the same box until about seven years ago when it was discovered the two fit together. At that discovery I began to believed these fragments had been separated at the time of manufacture since the right edge (left image) of each fragment has a different pattern of retouch. However, about three (3) years ago I learned from Dr. John Clark of BYU (1995:pers. com.) that these two pieces made an artifact that was similar to hafted, blade knives from Mexico. These blade knives were tapered, as is this channel flake, so they could be reversed in the haft. I now believe that this artifact was a hafted, reversible knife. Measurements are 18.5 mm (est.) and 2.6 mm thick.
1 Length is a difficult statistic to obtain since there are few if any, whole channel flakes. The 40 mm average I report in this document is my best estimate based on flute scars and an indirect method by which the sum of the length of all fragments are divided by the number of scars on preforms and finished points.
2 In Pelcin's Dissertation research, he conducted a number of experiments varying the angle of blow. He discovered that there were two types of flakes being created, based on the relationship between platform thickness and flake mass (1996: Figures 104-112). At the time he believed the two types might be cone and bending initiations, but this opinion did not make it into print. Subsequent work has convinced him that his original belief was correct.