11. Investigations
at the Flint Ridge State Memorial, Ohio, 1987-1988
By Richard
W. Yerkes, Ohio State University
In 1987 and 1988, the Ohio State University
summer field school in archeology was held
at Flint Ridge State Memorial. These investigations
were designed to collect a sample of artifacts
from the quarries and workshops that could
be used to analyze the prehistoric methods
used to extract the flint and produce the large
bifaces and bladelet cores of Flint Ridge Flint
that were transported to local and distant
sites. We also wanted to know if most of the
quarrying took place during the Middle Woodland
period, and if there were any habitation or
settlement areas adjacent to the quarries.
Limited survey and test excavations were conducted
during the two ten- week field seasons, but
a total of 123, 972 pieces of chipped flint,
10 hammerstones, an anvil stone, and one piece
of ground stone were recovered from 28 test
units and 75 surface collection squares.
Thirty Ohio State University students helped
with the cataloging and analysis of this large
volume of lithic materials between 1987 and 1993.
The final report on the Ohio State University
field school investigations and the collected
artifacts was submitted to the Ohio Historical
Society for curation in May 1993.
These field school investigations were certainly
not the first explorations at Flint Ridge. Study
of the "Great Indian Quarry" began in the 19th
century with the publications and correspondence
of Caleb Atwater (1820) and Samuel Hildreth (1838).
Several decades later, Gerard Fowke conducted
the first systematic study of Flint Ridge which
he published (under the pen name "Charles Smith")
in the 1884 annual report of the Smithsonian
Institution (Smith 1885). Flint Ridge was mentioned
in many late 19th and early 20th century discussions
of the "Moundbuilders" and their works, but the
definitive study of the quarries was conducted
by William Corless Mills for the Ohio Archaeological
and Historical Society (which he published in
1921). In 1933, the Flint Ridge State Memorial
was set aside by the State of Ohio to preserve
parts of the quarry site. Since then, Jeff Carskadden
(1969), James Murphy (1989) and others have investigated
several quarry, workshop, and habitation sites
in this unglaciated region in Licking and Muskingum
Counties, Ohio.
Remote Sensing
Grass and woods cover most of the
Flint Ridge State Memorial, so prior to the start
of the field school, a ground-penetrating radar
(GPR) survey of portions of the east field was
carried out to try and locate buried features.
Unfortunately, the GPR survey did not reveal any
clear subsurface anomalies. Twelve 2x2 m test excavation
units were opened in the east field, and two 2x2
m units were excavated 40 meters to the west in
the middle field. In the wooded area north of Flint
Ridge Road and east of State Road 668, two 1x1
m units were excavated near several quarry pits,
and a controlled surface collection of 75 one meter
squares was completed. At the suggestion of Martha
Otto (Ohio Historical Society), three 1 m wide
profiles were cut along the bank north of Flint
Ridge Road. In 1988, 12 additional 1x1 m squares
were excavated in the east field, and James Foradas
(Ohio State University) carried out a magnetometer
survey in the areas where the GPR survey had been
conducted. The only anomaly detected by the magnetometer
was a buried metal container.
Number and Density of Artifacts Recovered
An
average of 4,291 artifacts were found in each
of the test
excavation units, ranging from 383 in an historically
disturbed unit to 22,118 in one of the units
in the middle field. The average for the surface
collection
units was 51 artifacts. The density of chipped
stone in the test units ranged from 319 artifacts
per cubic meter of fill in the "disturbed" unit
to 42,117 artifacts per cubic meter in a unit located
where "natural" flint is exposed on the surface.
The average density of the test units was 7,046
artifacts per cubic meter. Of course, the bulk
of the artifacts at Flint Ridge would be classified
as debitage (flint chips, chunks of flint, or
other waste). Only 11 complete or broken projectile
points
were recovered, and only five of these could
be classified. One of the vexing problems facing
the
investigator at Flint Ridge is the lack of chronologically
sensitive stone tools (or pottery) among the
vast quantities of non-diagnostic flint artifacts
(cf.
Mills 1921: 171).
The Extent of the Quarries and Workshops
on Flint Ridge
The soils on Flint Ridge
contain large quantities of flint fragments,
and in places, large boulders
and outcrops of flint are found on the surface
(Wildermuth et al. 1938). The areas identified
as "flint-bearing soils" on the U.S.D.A. soil maps
for Licking and Muskingum counties were used to
estimate the geographic extent of the ancient quarries
and workshops (approximately 880 ha or 2,175 acres).
This is slightly less than the extent of the Vanport
flint beds on the ridge (about 1,000 ha). However,
these data do not provide an accurate estimate
of the number of quarry pits and workshops on Flint
Ridge. Fowke made a sketch map of the "hundreds" of
quarry pits around the crossroads and (Clark's)
blacksmith shop (see Holmes 1919). This area
now lies within the boundaries of the Flint Ridge
State
Memorial. The most detailed map of the extent
of the flint quarries is the one prepared by
Mills
in 1921 and modified by Ernest H. Carlson (1987:
416; 1991: 66), but it does not show the total
number of quarry pits or workshops.
Flint Ridge Flint is part of the upper member of the Vanport Formation
of the Allegheny Group of Pennsylvanian fresh-water and marine limestones,
clays, and coals. These beds formed during the transgressions and regressions
of a shallow sea that covered parts of Ohio, Pennsylvania, West Virginia,
and Kentucky around 320 million years ago. The upper member of the Vanport
Formation contains a flint facies that forms the cap rock of Flint Ridge
(because of its resistance to weathering). Flint Ridge Flint outcrops
in discontinuous weathered beds with an average thickness of 1.2 meters
(four feet) along the ridge. The outcrops have a lateral extent of several
kilometers.
Flint Ridge Flint formed in shallow, near shore, brackish waters at
the front of a delta. James Foradas noted that these kinds of shallow,
brackish water depositional environments produced flints that are not
homogeneous (like those formed in deep water settings) but have a high
degree of morphological, mineralogical, and chemical variation. Carlson
recognized four varieties of Flint Ridge Flint: (1) an impure, opaque,
massive, white flint and (2) a pure, translucent, bluish-gray flint.
Outcrops of these two types were common in and around the State Memorial,
while the third variety, (3) colorful, banded, ribbon flint, was more
common on the Nethers property in Muskingum County near the old Flint
Ridge school. The last type (4) is an impure, porous, light brown flint
with uneven fracture. It occurs along the western and southeastern portions
of the ridge. Much of the porous flint was unsuitable for lithic artifact
production, but early Euro-American settlers used it to make buhr-stones
for their flour mills.
Carlson's four part classification was used in our macroscopic analysis
of the artifacts from the test units at Flint Ridge State Memorial, but
recent work by Foradas (1994) showed how the geochemical variation in
Vanport cherts and flints could be used to discriminate between artifacts
made of Flint Ridge Flint and artifacts made of flints or cherts from
other sources (even if those other cherts look like Flint Ridge Flint).
The shallow basins along the shore of the "Vanport sea" received sediments
and detritus carried by streams flowing northwest from the Appalachian
highlands, the mineral composition of the flint deposits would vary from
basin to basin. The types of detrital minerals and their concentrations
in the flints of the Vanport Formation would differ from patterns observed
in other geological deposits. In addition, weathering of Flint Ridge
Flint would result in different abundances of secondary minerals filling
the fractures and cavities of the flint. By comparing the types and concentrations
of detrital and secondary minerals from different rock formations or
from different "quarry areas" with concentrations found in flint or chert
artifacts, it is possible to identify the type of flint that was used,
and even the specific quarry zone where the raw material was obtained.
The Age of the Quarries and Workshops
Mills (1921:
209-221) concluded that most of the manufacturing activities at Flint
Ridge were geared toward
the production of bifacial blanks (or "cache blades") and bladelet
cores and bladelets. These artifacts are associated with the Adena-Hopewell
complex. Six mounds and four earthworks were recorded along Flint Ridge,
and Mills
excavated an elaborate Hopewell burial at one of them (the Hazlett
Mound
on the western end of the ridge). The association of the mounds, bifacial
blanks, bladelets and bladelet cores suggested to Mills that the Hopewell
were responsible for much of the prehistoric quarrying and artifact
manufacturing on Flint Ridge. Six of the 11 points and point fragments
that we recovered
could be classified. Two Early Archaic types were identified: one MacCorkle
Stemmed and one Kanawha Stemmed, three Middle-Late Woodland types were
found: two Jack's Reef points and a Raccoon Notched point. A Late Prehistoric
triangular point was also found (Madison type). The temporal range
of the points indicates that the Flint Ridge quarries and workshops
have
been
operating for the past 9000 years.
Changes in the Utilization of Flint Ridge Flint Through Time
Lepper (1989)
noted that there are many reports that artifacts made of Flint Ridge Flint
have been found at sites across Eastern North America, but the most reliable
of these reports involve finds from Paleo-Indian or Middle Woodland sites.
Prufer and Baby (1963) found that FRF was the second most common raw material
used for Paleo-Indian points found in Ohio (after Upper Mercer chert) and
Lantz (1984) reports that Flint Ridge Flint was the third most common raw
material used to make the Paleo-Indian points found in western Pennsylvania
(after Upper Mercer and Onondaga chert). This suggests that Flint Ridge
Flint was often utilized by the earliest inhabitants of this region. Carskadden
(1969) suggests that the use of Flint Ridge Flint increased during the
Archaic period (7,000 to 3,000 B.P.), but that extensive quarrying operations
on Flint Ridge probably did not begin until Early Woodland times. Murphy
(1989:35) found that Flint Ridge Flint artifacts and debitage were common
at Archaic and Woodland sites in the Hocking Valley (there are very few
recorded Paleo-Indian sites), and like Lepper and Carskadden, he believes
that the most intensive exploitation of Flint Ridge occurred during the
time of the Adena-Hopewell (2500 to 1500 years ago). During the Late Woodland
and Late Prehistoric periods (1500 to 400 years ago) there seems to have
been a decline in the use of Flint Ridge Flint (Carskadden 1969; Lepper
1989; Murphy 1989).
It is clear that the Flint Ridge quarries and workshops were used to
manufacture Adena/Hopewell bladelet cores and bladelets. The area that
we investigated in 1987 and 1988 was within the zone of workshops "south
and southeast of the blacksmith shop" where Mills (1921: 215) found that
most of the core-and-bladelet manufacturing took place. In fact Mills
remarked the bladelet cores and bladelets were rarely found outside of
this area on Flint Ridge. We did not find any evidence for the production
of Paleo-Indian artifacts (e.g. fluted points) during our investigations,
although we did recover several Early Archaic projectile points. The
impression that one gets from this is that the most intensive utilization
of the Flint Ridge quarries was during the Adena/Hopewell times (as everyone
has suggested), however this may be due to the fact that the "cache blades," bladelets,
and bladelet cores that serve "type fossils" for the Early and Middle
Woodland periods are easy to recognize. The flakes and cores that are
the byproducts of flake core and biface manufacturing are much more generic.
It is possible that the area of Flint Ridge that we tested was not intensively
utilized until Adena-Hopewell times, or evidence for earlier and/or later
uses of the area may have been masked by Hopewell core-and-bladelet production.
Quarrying and Stone Tool Production
Mills
(1921) identified three stages in the manufacturing of bifaces at Flint
Ridge. The first stage was quarrying
the flint, the second stage was "blocking out" the flint into general
bifacial form before it is taken to the workshops, and the third stage
was shaping the blocked-out pieces into bifacial blanks or cache blades
that could be transported to distant
sites where
they could be made into points, drills, or other bifacial tools. Mills
noted that the workshops where the third production stage took place were
located near the quarries on Flint Ridge and at more distant locations.
Since Mills' day there have been a number of technological studies of
biface manufacturing based on modern replication experiments (Ahler 1986;
Callahan 1979; Johnson 1979, 1981). These studies revealed that one of
the most crucial factors in biface production is maintaining the width
of the tool while reducing the thickness. The thinner the biface, the
more nearly complete it is (Johnson 1981: 13). The ratio of maximum width
to maximum thickness is a key element of Callahan's (1979) five-stage
biface manufacturing sequence (Ahler 1986: 59). Callahan's scheme takes
Mill's three production stages (which take place at or near quarries)
and adds two final stages when the "finishing touches" are given to blades.
Callahan's Stage 4 bifaces have been secondarily thinned, and exhibit
noticeably flattened cross-sections. His Stage 5 bifaces are prepared
for use and/or hafting. They are preforms for projectile points, bifacial
knives, or other tools.
| Stone Tools
The oldest known human-made tools are made from
stone and have been found in Africa. From the earliest stages
of human evolution, until the discovery of metal-working techniques,
people have used stone to make tools. The two basic techniques
of making stone tools involve grinding a stone into the desired
shape, or chipping flakes off the stone until the desired shape
is achieved. Flint is the most commonly used rock for the manufacture
of chipped stone, and the flint found at Flint Ridge State Memorial
was used by prehistoric Indians throughout Ohio. Archeologists
give specific names to the products and bi-products of stone
tool manufacture. Some of these include:
core - the original block, cobble
or slab of rock from which flakes have been removed. Cores are
frequently found at quarries and other sites close to the source
of the raw stone material.
flake - a piece of stone that has
been chipped from a core or other stone tool. Flakes are recognized
by the presence of a striking platform and bulb of percussion,
which are located at the point where the flake was removed from
the core. The presence of a striking platform and bulb of percussion
helps archeologists distinguish between natural pebbles and human-made
stone chipping debris.
blade - a blade is a flake that
is made from a specially prepared core. Blades are at least twice
as long as they are wide, and have straight, parallel sides.
One of the characteristics of Hopewell sites in southern Ohio
is the presence of small blade-lets made from special blade cores.
biface, bifacial - this refers
to tools that have been chipped on opposing surfaces to shape
a piece or produce a working edge. A bifacial cutting edge is
similar to sharpening both sides of a knife blade. Most arrow
and spear points are bifacially shaped. If a stone tool is chipped
on only one surface, it is called a uniface. Scrapers and spokeshaves
are examples of unifacial stone tools. |
Mills (1921) implied that the final shaping of bifaces
made of Flint Ridge Flint would probably have taken place at domestic
sites away from the quarries and workshops. However, he did find a number
of finished projectile points and some finely retouched bifaces that
would be classified as Stage 5 bifaces at Flint Ridge, but it is not
clear if these final stage bifaces were found in the quarry zones or
at some of the workshops such as the "Graham place" that also
contained domestic refuse (Mills 1921: 219).
We recovered 152 bifaces in our test units at Flint Ridge State Memorial.
Eleven of these were points that may have been brought to the quarries
and workshops and discarded during "retooling" operations.
Of the remaining 141, nearly half of the bifaces that we recovered from
workshop areas near the quarries were stage 2 bifaces, while 43% exhibited
the primary or secondary shaping that Mills described as occurring during
stages 3 and 4. Only 8% could be considered preforms or "finished" bifaces
(stage 5). It should be noted that 10 of the 11 stage 5 bifaces (or preforms)
were broken, and the types of fracture that they exhibited suggested
that they had snapped during manufacturing.
Jay Johnson (1981) used a thinning index in his study of biface production
trajectories in Mississippi. He suggested that the ratio between the
weight of the biface and its surface area is a more accurate gauge of
how "complete" or "finished" the biface is. He found
that a thinning index >= 3.1 gm/cm2 identified early stage bifaces
that are usually found at quarry sites, while an index between 1.7 and
3.1 is typical of middle stage bifaces, while late stage bifaces would
have a thinning index <1.7 (Johnson 1981:25).
The computed thinning indices for the 49 whole (or nearly whole) bifaces
from Flint Ridge averaged 0.90 for the points, 1.74 for the small thin
bifaces, 1.72 for the large thin bifaces, and 2.43 for the crude unpatterned
bifaces (only two of the 34 crude bifaces had a thinning index that was >=
3.1). This shows that while the later stage bifaces from Yellow Creek
and Flint Ridge were thinned to the same degree, the early stage bifaces
were thinner at Flint Ridge. Johnson found that 92% of the bifaces at
his quarry sites were early stage bifaces (similar to the crude bifaces
found at Flint Ridge), while 87% of the bifaces found at his late stage
biface manufacturing workshops were thinned or completed types. There
seems to have been a distinct separation of the biface production trajectory
between Johnson's quarry sites and late stage workshops. In our sample
from Flint Ridge, we found that 54% of the bifaces were early stage types
(crude) while 46% were later stage forms. The complete biface trajectory
seems to be represented at the Flint Ridge State Memorial, without the
spatial separation of production stages that was observed in the Yellow
Creek region.
The Hopewell Bladelet Industry
The second industry that Mills (1921) recognized at Flint Ridge involved
the manufacture of bladelet cores and bladelets. He noted that most of
the bladelet cores were manufactured at workshops located south and southeast
of the crossroads at the blacksmith shop (within the boundaries of the
Flint Ridge State Memorial). Mills found that the manufacturing carried
on at the Flint Ridge workshops was aimed at producing bladelet cores
rather than bladelets. He mentioned that many of these bladelet cores
were carried to distant points where bladelets could be struck off as
needed (1921: 219). Our investigations confirmed this. We recovered over
800 bladelets or fragments (most of which were struck off during the
early stages of blade core preparation), but only a dozen bladelet cores
or core fragments. The bladelet cores seem to have been produced by free-hand
percussion. Most of the bladelets and bladelet fragments that we recovered
had large striking platforms. The flaking scars on the cores and bladelets
suggest that hard and soft hammers were used. Almost all of the bladelet
cores and core fragments that we recovered were heat-treated, and 59%
of the bladelets and fragments showed some sign of heat treatment (luster,
crazing, or potlids). This suggests that some bladelets were struck off
the cores before they were heated. While it appears that the heat treatment
of bladelet cores took place at the quarry workshops, we did not find
any features that could be classified as heat-treatment facilities during
our excavations.
We found no evidence for restricted access to the Flint Ridge Flint quarry
zone. We exposed no habitation features during our testing program. Mills
(1921) concluded that the Flint Ridge Flint quarries were common property
among the tribes of the Ohio Valley. He noted that the only place on
Flint Ridge that seemed to have a more or less permanent abode was the
Hopewell Hazlett Mound that he excavated on the extreme western edge
of the quarry zone. Mills (1921: 219) mentioned another habitation site
on Flint Ridge that was found at the "Graham Place." He referred
to this site as a workshop that contained pottery, animal bones, and
evidence for a more or less permanent habitation. Murphy and Morton (1984)
argue that the Graham site is identical to the Dodson Village that is
described by Bernhardt (1976) as a production/distribution site in the
Hopewell exchange network. Murphy and Morton relocated the Dodson/Graham
site approximately 1 mile south of the Flint Ridge State Memorial. They
reviewed the history of excavations at the site, reexamined the ceramics,
lithic artifacts, and faunal materials, and concluded that the Dodson/Graham
site was occupied for very short periods of time by small groups of people
that came to the Flint Ridge quarries to obtain flint. The most frequent
use of the site was during the Early, Middle, and Late Woodland periods,
but it cannot be demonstrated that the flint quarrying and lithic manufacturing
that went on at the Dodson/Graham "village" was linked to any
larger lithic production and distribution system. The results of these
kinds of investigations support Mills' conclusion that there was no restricted
access to the quarries and that there do not appear to have been any
permanent habitation sites on Flint Ridge. Our 1987 and 1988 investigations
were limited to the Flint Ridge State Memorial, and we were not able
to obtain data on the distribution of Flint Ridge Flint outside of the
primary source area. The prehistoric exchange and redistribution of Flint
Ridge Flint among ancient societies in Ohio and other regions of North
America may have reached its peak during the Early and Middle Woodland
periods, but most of the evidence for this has come from sites found
outside of the quarry area.
Our two short seasons at Flint Ridge allowed us to test several methods
of data collection, and to train students in archeological field methods.
Our work supported most of the earlier observations made by Mills about
the nature of the activities at Flint Ridge. We agree with his observation
(Mills 1921: 224) that, "It is very fortunate for those who wish
to verify or disprove the statements made in this study of Flint Ridge
that the full range of quarrying is still well within the reach of all
investigations and needs only to be properly examined to reveal the facts." It
is hoped that in the future, archaeologists will continue the investigations
at Flint Ridge that he and Fowke began nearly a century ago.
Acknowledgments
Martha Potter Otto, Don Bier, Dick Boisvert, and Brad Lepper of the Ohio
Historical Society assisted in the planning for the 1987 and 1988 investigations
at Flint Ridge and provided advice and encouragement during the excavation,
survey and analysis stages of the project. Richard Livingston and his
staff at the Flint Ridge State Memorial provided facilities to store
equipment and artifacts and their help made it a real pleasure to work
out at Flint Ridge. Funding for the Ohio State University summer field
schools was provided by the Department of Anthropology and the Office
of Continuing Education. All of the 1987 and 1988 field school students
helped with the processing and analysis, but Linda Gaertner, Tammy
Gibson, Kelly Grubb, Andrea Isgro, Laura Jordan, Rory Krupp, Jim Maxwell,
Terry McCarthy, Stephen Paris, Bill Pickard, Karen Redmond, Kathy Saul,
and Pam Thorne deserve special thanks for their help. Albert Pecora
III put much time and effort into the technological analysis of the
Flint Ridge artifacts.
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