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

leaf bifaces, which also can be partially tapered at the base. The points are made of
medium- to fine-grained materials using soft- or hard-hammer percussion, and then
finished with a nonpatterned, more or less colateral, pressure-flaking technique.
5.4.1.2.9: Medium and small straight-stemmed biface (see Figure 5.2 #18 and #32). The
base of this biface is chipped into a straight stem, probably by pressure, and features
relatively small shoulders or tangs. This type is not in evidence at Piedras Negras, but
seems to be common to the Pasión region (see Willey 1972), during the Late Classic. A
different hafting technology may be indicated by the stem preparation. The medium-sized
tools may have been used as spearheads, or less likely as knives, while the smaller ones
may have been used as dart points. Other straight-stem forms occur later in the northern
Yucatan, possibly as a marker for the Postclassic period. They are often pressure flaked,
revealing heightened skill on the part of the knappers who made them.
5.4.1.2.10: Medium and small side-notched biface (see Figure 5.2 #19 and #33). These
types appear to have been made by notching a bifacially-worked, laurel leaf form. This
type has not been found at Piedras Negras, and like the straight-stemmed modification, it
implies a slightly different hafting technology. For both the side-notched and straight-
stemmed bifaces, it is unclear whether they were intended to be knives or points.
Analysis of the breakage pattern and use-wear would be necessary to properly identify a
function for these pieces.
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