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

iface-reduction flake made of a rough-texture material likely was derived from the
production of large- and mid-sized, thick bifaces. Large- and medium-sized, thick
bifaces, usually celtiform, are never made of fine microcrystalline-quartz materials. If the
material is fine-grained, then it is possible to infer that the flake was part of a thin-biface
trajectory.
The most indicative types of flakes are late-stage biface-reduction flakes because
they carry the most information about the final product. Late-stage biface-reduction
flakes are identifiable by (1) well-prepared multi-faceted platforms; and (2) a fine flaking
pattern on the dorsal side of the flake. More flake curvature and a wide, platform-to-
dorsal-surface angle indicate that the flake was removed from a thick biface. When a
flake features less curvature, which is uncommon at Piedras Negras, and the material is
fine-grained, the end product probably is a thin biface. Finally, if the material is of a
normal-to-fine texture, and the flake is small in size, the end product likely was a
medium- or small-sized thin biface.
Uniface-reduction flakes are not common at Piedras Negras, and they are difficult
to identify, but they do have a number of distinct technological traits. The first is the
platform, which should be single-faceted, but not have any traces of a negative bulb.
There usually is no cortex on the platform because the striking area should be the ventral
side of the flake-blank. Although I differentiate between the sizes of the flakes (i.e.,
small, medium, and large), it is impossible to determine the form of the end product. The
easiest uniface-reduction flakes to identify feature well-developed, bi-directional flake-
patterns on the dorsal surface.
201