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

section, and then were prepared and reduced in a number of (Figure 6.3) different
ways.
One of the most popular ways Piedras Negras knappers reduced imported cores
was the pressure reduction of blade-cores on one or more sides. The best evidence for this
reduction strategy is exhausted cores that feature a lenticular cross section with pressure
scars on one face of the core and percussion scars on the other (Figure 6.1, upper row).
Consequently, the cross section of the core changed through its use-life, probably most
often from circular to oval, and finally, to a nearly lenticular or “flat” morphology. Small
percussion flakes and blades were removed during the initial preparation of the core and
after pressure reduction had already begun.
Percussion blades and flakes from household fill and royal caches, which were
further modified into eccentrics, indicate that there was a systematic method of core
preparation and core maintenance at Piedras Negras. First, wide percussion flakes were
removed from one face of the core (Figures 6.3 and 6.5) to isolate a centrally located
platform (Figure 6.3). Next, a long, thin blade was removed from the central working
face of the core (Figure 6.6). If necessary, flakes and blades were removed from the distal
end of the core to complete regularization (Figure 6.7). This spare regularization strategy
was all that was required to begin the pressure reduction of the core. The best examples
of these kinds of initial production-debitage come from Yaxche period caches. Since the
obsidian eccentrics from this time are little modified, they retain much of the original
evidence of blade production and core preparation on their dorsal surfaces (Figure 6.8).
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