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

any other residential group at Piedras Negras. Although there is no evidence that the U
group was producing blades before Yaxche times, there is strong evidence for production
activities, which spanned from the Yaxche times to the abandonment of the site. Scant
evidence of obsidian-eccentric production was also found in PN33 excavations (see
below), indicating that the U Group was involved in the production of a variety of
chipped-stone goods. The R Group, designated by Operation PN23, does not appear to
have been a blade producer during the Yaxche phase, nor the Kumche phase, but like
other households during Chacalhaaz times, it features strong evidence for prismatic-blade
production. A few burials in this household group are interred with prismatic blades, and
in one case, a range of imported obsidian blades, suggesting that this residential group
had access to fine obsidian products. PN23 likely received the majority of its blades from
the nearby PN33 household group.
Little or no evidence of blade production was found in PN15 excavations, nor in
the more distantly located residential groups represented by the PN57 and PN62
operations. It is possible that further excavations in the PN57 household group could
yield secure evidence of production, especially for the Chacalhaaz phase, but at this time
there is not the full range of production debitage present in this area. Although PN15
appears to have been involved in the manufacture of small bifaces by pressure during the
Late Classic, it is clear that this group was not involved in a pressure-blade industry.
The near-periphery excavations uncovered a strange variety of obsidian artifacts
and the there is much variation between the samples of these households. Although the
residential groups investigated in the rural survey (RS) are situated close to one another,
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