The Organization of Chipped-Stone Economies at Piedras Negras ...

5.4.1.2: Medium-sized artifacts (8 cm to 12 cm in length).
5.4.1.2.1: Medium celtiform biface, thin (see Figure 5.2 #10). This type was
manufactured with a direct percussion technique. It is between 8 cm and 12 cm in length,
and is wider at the proximal end than the distal. The margins were finished with a
pressure-flaker. A thin, lenticular cross section was a desired result of the reduction
process.
Often called a teardrop point, these bifaces have the same celtiform outline as larger
versions, but technology, morphology, and often material, are not the same. Function also
is different in most cases with the focus of use moving to the proximal end rather than the
distal end. In some cases, however, the proximal end does not have a finished point,
which may suggest that these celtiform bifaces were used more often as knives than as
spearheads. One possibility is that these bifaces, and their smaller counterparts, small and
medium laurel leaf bifaces, were first used as projectile points or atlatl dart-points, and
were then later transformed into knives and chisels when the fine edge was removed
through breakage or resharpening. For example, in a peripheral household group where
hunting and military protection may have been important activities (Operation R6;
Webster and Kovac 1999), bifaces that appear to be projectile points were intensely used
as knives and scrapers. Reworked impact fractures and bending breaks found on some
examples add credence to this argument (see Figure 5.6 for a reworked example). Thin,
celtiform bifaces are one of the most common medium-sized, fine bifaces at the site, but
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