| Remarkably, there have not been
detailed studies of the obsidian de-posit to
determine if the character of the Mound 11
flake assemblage truly is consistent with the
kinds of flakes that result from the production
of large bifaces. Hatch et al. (1990) examined
a very small sample of the flakes to study
the chemical characteristics of the ob-sidian
and the thicknesses of the hydration rinds.
Their “cursory ex-amination of 19 artifacts
from the cache material suggests ... that it
consists entirely of flake blades, core fragments,
and small bifacial tools produced by a percussion
blade-core technology” (Hatch et al.
1990:463).
Two alternative interpretations of the obsidian
deposit are thus posed. In one scenario, outlined
by Shetrone (1922, 1930), the flakes are by-products
of the pro-duction of Ross points and other
very large bifaces found at Hopewell and at
some other Hopewellian sites. In that case,
the several deposits of obsidian bifaces and
the flakes are related and might be more-or-less
contemporaneous. In contrast, Hatch et al.
(1990) suggest that the flake deposit and the
biface deposits represent “in-dependent
reduction sequence(s).” In that case,
the bifaces and flakes could have been obtained,
although not necessarily, from sepa-rate source
localities, and the arti-facts could differ
both in the dates of production and dates of
deposition (Hatch et al. 1990; see also Hughes
1992; Stevenson et al. 1992).
The character of the flake assemblage, then,
has bearing on the intrasite chronological
relationships of different ritual deposits
and different mounds within the Hopewell site.
It also has implications for long-standing
questions about the mechanisms of obsidian
transport from the Rocky Mountain region to
the Midwest (e.g., Griffin 1965; Griffin et
al. 1969).
Comments on Context
The well-known photograph of the obsidian
deposit (Shetrone 1926: Fig. 10; Shetrone
1930:Fig. 125; Hatch et al. 1990:Fig. 2)
does not show the deposit as first found.
As recorded in the field notes, excavations
began on the south side of the mound, and
the edge of the deposit was encountered almost
immediately (Figure 1). The entire deposit
was removed over two days (Shetrone 1922:
22 and 23 August). The character of the deposit
and the two portions of mica cutouts and
a cut and polished, though likely unfinished,
piece of calcite are described in the notes
in some detail. Excavations continued to
the east where a small ritual basin was encountered
(Figure 1).
As work continued north, the cre-mated burial
was found. Some time after this, apparently
for pho-tographic purposes, at least some
of the obsidian was returned to the floor.
Mica pieces and the small polished stone
that had originally been found within the
deposit were placed in full view. It is possible
that one of the pieces of mica in the photograph
was found with the cremated remains. In addition
to general concerns about interpreting a
staged photograph, we have questions about
the line of stones in the photograph that
partially en-circles the artifacts and the
cremated remains forming a “grave.”
After the cremated remains were uncovered,
Shetrone (1922: 23 August) writes “it
was clearly to be seen that the obsidian
deposit belonged to it [the burial], since
a row of scattered boulders, from one to
five pounds, extended from the south side
of the crematory, around the deposit and
the burial.”
In the photograph the blade of the trowel
points south. This direction is consistent
with the relative locations of the deposit,
basin, and burial as described in the notes
and map (Figure 1). The mantle over these
features is described as “unproductive
gravelly loam composing the body of the mound” (Shetrone
1922: 29 August). Many possible “boulders” are
clearly visible in the fill seen in the photograph.
No stones were mentioned at the edge of the
obsidian deposit as work began and proceeded
from the south. The cobbles in the photograph
were apparently placed for the photograph
after the deposit was removed and then re-placed.
Such a line is not a com-mon Ohio Hopewell
grave marker. While there is much individuality
in grave construction, we do not con-sider
the evidence in this case suf-ficiently clear
to positively place the obsidian deposit
within any grave. The individual buried near
the deposit, and perhaps the indi-vidual(s)
represented by the charred human bones found
in the backfill over the round ritual basin
on the north side of the mound, may all have
been “master artisans.” This
connection is a reasonable interpretation
that is hard to prove.
Examination of the Collection
On May 7, 2002, we conducted a preliminary
survey of the Mound 11 flake collection
at the Ohio His-torical Society curation
facility. The examination convinces us
that there is much to be learned from this
unique deposit and its context, and additional
study is planned. Martha Otto, Cheryl Johnston,
and William Pickard facilitated our study
and deserve our great ap-preciation.
The obsidian pieces are cataloged under accession
number 283 and stored in eight cardboard
boxes (ca. 0.84 ft² each). Within the
boxes, the flakes are packed into heavy paper
bags, a variety of plastic boxes, and a few
plastic zipper-seal bags. The flakes are
size-sorted to some extent as some boxes
and bags contain ob-sidian pieces of approximately
the same size. Dirt still adheres to some
of the obsidian flakes within the paper bags.
The collection consists of many tens of thousands
of obsidian arti-facts, and our examination
thus far has been necessarily cursory. We
surveyed the contents of each plastic box,
although some boxes and bags received more
concentrated attention than others. The contents
of some bags were spread out on separate
trays to better examine the contents; in
other cases we just peered into the bag to
get a sense as to whether or not the contents
were similar to that of adjacent bags.
Many pieces were individually studied in
detail, although most flakes were just visually
scanned. We have not yet undertaken for-mal
coding or measurements of any of the flakes,
and appropriate sampling and quantification
procedures for a formal study are yet to
be worked out. Nonetheless, we feel we can
make a number of solid qualitative observations
about the collection and some reasonable
inferences about the behaviors that created
it. We also separated 29 obsidian flakes
that may be an appropriate sample for a planned
energy dispersive x-ray fluorescence (EDXRF)
analysis to be performed by Richard Hughes.
In addition to obsidian, we encountered some
other notable items within the storage boxes.
Box 12 contained several non-obsidian artifacts
that we sorted out and placed into separate
small, plastic zipper-seal bags. These materials
include tiny mica pieces, fragments of quartz
crystal, very small pottery sherds including
a rim sherd, faunal fragments, two tiny copper-stained
organic fragments (bark?), one copper fragment,
chert flakes, and modern debris probably
from excavation or curation storage. The
unanticipated discovery of a small sample
of wood charcoal in the collection engendered
much excitement and provides us the first
opportunity to obtain radiometric age estimates
for Mound 11 and its deposits. The radiocarbon
age estimates are presented and discussed
below.
Production Technology
and Behaviors
The most striking characteristic of the Mound
11 obsidian flakes is that the entire assemblage
results from the production of many very
large bifaces. Much of the assemblage consists
of relatively large, broad flakes with relatively
little longitudinal curvature. The dorsal
surfaces bear multiple flake scar facets,
many of which show multiple flaking orientations.
Most flakes are fragmentary. Striking platform
remnants are relatively small, infrequently
cortical, and many are multifaceted with
platform edge (dorsal surface) trimming and
platform edge abrasion. These flake characteristics
are common traits of bifacial tool production.
In marked contrast to the technological assessment
of Hatch et al. (1990), we see absolutely
no evidence that the flakes represent a “percussion
blade-core technology” or bladelet
production. In fairness to Hatch and his
associates, it is worth remembering that
they were not conducting a technological
analysis and examined only 19 specimens out
of the tens of thousands of flakes in the
collection.
The bifaces from which many of the flakes
derived were very large. Many flake fragments
are greater than 6 cm in length along the
flaking axis, and we estimate that many of
those fragments represent individual flake
removals that could easily have been 15 cm
or more in length. Such large biface thinning
flakes indicate that the bifaces were a least
15 cm in width at some stage in the reduction
sequence. The relative “flatness” of
the flakes along their longitudinal axes
indicates that the bifaces had relatively
biplanar (flat) cross sections. The thinness
of many of the flakes, especially relative
to overall flake size, indicates that the
bifaces were carefully “pared” to
smoothly contoured surfaces.
These flakes, then, are entirely consistent
with the production of Ross “points” and
other very large, relatively thin, biplanar
bifaces such as those known from Mound 25
and elsewhere at the Hopewell site. Some
of the Hopewell site bifaces were as much
as 25 to 38 cm in length (Greber and Ruhl
2000:147–154; Moorehead 1922: 132)
and tend to be much larger than the obsidian
bifaces recovered from Mound City, Fort Ancient,
or other Ohio Hopewell sites.
The Mound 11 flake assemblage was produced
by virtuoso flintknappers (we have no opinion,
at present, as to whether one or more knappers
were involved). The knappers were accomplished
in the flaking of very large, broad, and
thin bifaces, and it appears that they were
also quite familiar with working obsidian.
There are no broken or otherwise mishandled
bifaces in the Mound 11 collection, and we
have not yet noticed any knapping errors
in the flake assemblage.
It appears likely that the Mound 11 obsidian
deposit consisted of flakes only from successful
production episodes and that flakes from
unsuccessful attempts were deposited elsewhere.
Nonetheless, given that neither the making
of such large, thin bifaces nor obsidian-working
were common practices for the Middle Woodland
people of Ohio, it is intriguing to contemplate
how and where such practiced expertise would
have come into being.
The Mound 11 obsidian flake deposit is also
biased in that the deposit lacks the small-sized
end of the flake spectrum. The smallest flake
fragments in the extant collection are approximately
finger-nail-sized or about the size that
would likely be collected by hand and transported
from the original production sites. Although
we do not expect that micro-debitage would
have been collected in a 1922 excavation,
we do suspect that Shetrone would have attempted
to recover quite small obsidian flakes from
such a context. It is unlikely that the thousands
of pieces contained those flakes at the time
of deposition.
Cortex-bearing flake surfaces are not rare
in the assemblage. The nature of the cortex
suggests that the obsidian was obtained directly
from in situ obsidian flows rather than from
secondary deposits such as stream cobbles.
The presence of cortex and of internal flaws
suggest that the obsidian was only minimally
tested and reduced prior to transport from
the source region to Ohio. Some bifaces,
however, were made from large flakes as evidenced
by the presence of so-called “Janus
flakes” — flakes whose dorsal
surfaces were the ventral surfaces of larger
flake blanks.
The obsidian is quite varied in its visual
appearance. Some is very deep black, smooth,
and glassy; some is opaque even at the thin
edges of flakes; some translucent to transparent;
some is milky; some has light banding; and
some contain numerous phenocrysts. We can
not say whether or not this visual variability
reflects different obsidian sources.
Finally, we would note that much of the debitage
placed within the Mound 11 deposit was sufficiently
large that it could have been used to make
everyday Hopewellian Middle Woodland retouched
tools, which tend to be relatively small.
The raw material potential of the obsidian
debitage, therefore, was not “economized” any
more than were the large bifaces that were
placed with other ritual deposits at the
Hopewell site. Partly for this reason, we
find it rather unlikely that the edge damage
so common on the Mound 11 flakes represents
use-wear as interpreted by Hatch et al. (1990:463).
Instead, the edge-damage probably represents
both prehistoric and relatively modern “curation
damage” to thin, very fragile flake
edges.
Dating the Deposit
The results of two radiocarbon assays on
wood charcoal sorted from the deposit are
consistent with each other (Table 1). Their
average, at one sigma, dates the placement
of the obsidian debitage to 1745 ± 40
years BP. This does not necessarily date
the chipping of the large bifaces that produced
the debitage. Dates for this chipping, based
on the thicknesses of the hydration rinds
found on 19 pieces from the deposit, have
been published (Hatch et al. 1990). However,
several technical problems associated with
the method used prevent complete acceptance
of these dates (e.g., Hughes 1992).
Technical problems associated with measuring
the depth of the rind itself have been overcome.
Work continues to find appropriate temperature
values that are needed in the theoretical
equation translating rind depth to chronological
time (e.g., Lepper, Skinner and Stevenson
1998). The success of this work could answer
questions concerning the length of time of
active use of obsidian by Ohio Hopewell artisans.
The dates in Table 1 reflect the end of this
major use.
Conclusions
Our very brief survey of the Hopewell Mound
11 obsidian indicates that there is much
to be learned by further study of the collection.
Of all the exotic raw materials employed
by Hopewellian peoples, obsidian was the
commodity whose original source was farthest
from home. As the only substantial assemblage
of Hopewellian obsidian debitage known in
Ohio, study of this flake collection remains
the best pathway for understanding the mechanisms
and motivations by which obsidian made its
way from the Rocky Mountains to the Midwest.
More formal and detailed studies of small
sub-samples of the collection are pending.
Even the brief study to date emphasizes the
importance of the information that is still
to be found in museum collections, in this
instance a collection that has been safely
curated for eight decades.
Acknowledgements
We thank the Ohio Historical Society for
allowing us to examine the Mound 11 assemblage
and for giving permission to date a charcoal
sample found within the collection. We especially
thank Martha Otto, Curator of Archaeology,
for facilitating our study.
Funding for the AMS radiocarbon age estimates
came from donations made to the Hopewell
Research Fund at the Cleveland Museum of
Natural History.
Table 1. Mound 11 radiocarbon age estimates.
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