Archaeological studies are limited by the fact that they must
rely on the materials that are preserved in the ground. Only in extraordinary circumstances are materials such as
textiles, leather, wood, or basketry preserved in archaeological sites: in most
circumstances, we can only infer their presence. Further, archaeology relies upon the
study of material remains: we can only speculate and make inferences about how tools
were used, why they were made, or what their users thought, intended, or believed. Nonetheless, artifacts
and archaeological features provide a picture of the material culture and the technology
of a group and people. In a site like the Emeryville Shellmound, which represents a long
period of occupation, we also can investigate changes in artifact types and styles over
time, which may be indicative of new contacts, between cultures, or technological advances.
The 1999 excavation at Emeryville Shellmound recovered
over 1800 artifacts or groups of artifacts. These fall into four general technological
and material classes: bone tools, chipped stone
tools ("arrowheads" and cutting tools), groundstone (mortars, pestles and charmstones),
and shell (ornaments and beads).
The bone tool complex could be considered as two
subclasses; bone awls and other tools presumed to relate primarily to the production of basketry and leather items; and
bone whistles, spatulas, pendants and pins, which may have had more ceremonial or
ideological uses. A wide variety of well-made bone tools in large numbers were
recovered from the excavation. Most common of these are implements of the awl
type; elongate pointed tools presumed to have been used for perforating activities such as sewing and
basketry or possibly as implement points in hunting and fishing. Studies by a zooarchaeologist indicate that a standard manufacturing
technique was used to produce many of these specimens. To make an awl, an animal
leg bone was selected, most often the front leg of a deer or elk. A sharp-edged stone tool was
used to cut a groove around one end of the bone and the head of the bone was
snapped off. Next, the bone was grooved lengthwise so it could be snapped in half to produce two
elongate "blanks", each with a portion of the remaining head of the bone at one end.
Narrower forms could be produced by repeating this process. Finally, an abrasive stone
sometimes
was used to smooth the split edges at the "handle" end, and shape the
opposite end to a
point. Although modern basket makers suggest that the Emeryville tools may not have
been sufficiently fine-pointed to be useful for coiled basketry, they could have been used
to make the coarser twined baskets. Sewing and working of hides at the site is inferred
from the abundance of perforating tools, which included a number of thin, eyed tools
presumed to have been used as needles. Some graves include sets of
elongate, spatulate bone objects that may have been ornaments. The arrangement of perforated
bone ornaments in
graves also suggests that such ornaments may have been attached
originally to
clothing or headgear of hides or textile. Groups of bone tubes or
whistles also were found in some graves. Likely these were musical
instruments. They may have had a role in ritual practices as well.
The major components of the chipped stone category are
projectile points and cutting tools of obsidian and
chert. These are believed to have been used for hunting, meat
processing and other tasks where a sharp edge was useful. Siliceous rocks (high in silica)
were used for these tools because it is possible to control the way they fracture, to create
shaped sharp edges. Chert was available locally. The nearest obsidian sources were in
Napa and Sonoma counties, but some obsidian in the site came from the eastern Sierra as
well. Obsidian almost certainly was obtained in trade. Among the collection of chipped
stone tool manufacturing debris (debitage) from the big mound, there was only about
one-third as much obsidian as chert, although obsidian and chert are equally represented
among finished tools. Obsidian tools and projectile points often show evidence of
reworking of broken and worn tools. This suggests that obsidian was relatively scarce and
valuable. It is possible that much of the obsidian at the site was obtained in relatively
small pieces, or even in the form of ready-made tools which, if broken, were reworked
and reused. Chert waste material was much more common in the deposit.
Chert was used at the site for large flake and core
tools, as well as in the production of large projectile points. Chert probably was relatively
easy to obtain and therefore less valuable. A number of small serrate obsidian projectile
points were found in the most recently occupied part of the shellmound site. Points of
this style are common in central California during the late period. Antler tools found at
Emeryville probably were used in the manufacture of chipped tone tools.
Groundstone tools are shaped by abrasion. For production
of mortars and pestles, (grinding bowls and pounding implements), the most common rocks at Emeryville were
vesicular basalt, obtained from the East Bay hills, and sandstone, probably available as
stream cobbles in the bed of Temescal Creek. Mortars of several forms were shaped
from large cobbles. In some cases a basin was ground into the interior of a rounded boulder,
with only minimal shaping of the exterior. Other mortars, particularly in the later period,
were fully shaped both inside and out, and have a squared-off rim and sloping walls of
even thickness. The pestles recovered generally are based on elongate stream
cobbles, with minimal elaboration. Ethnographically, mortars and pestles were used to grind
berries and meats, as well as seeds and acorns.
Also of interest at Emeryville is the wide variety of
"charmstones". These are small globular or elongate cobbles
of sandstone or other finer-grained rocks, shaped in a variety of plummet-type forms, and often smoothly polished.
Early types are perforated at one narrow end, while others often have markings of asphaltum and twine, indicating that a
cord was attached at one end, probably for suspension. Many specimens have battered
faces or tips. There is little ethnographic evidence of how "charmstones" were used. It
has been suggested that they were attached to fishing or hunting nets as hunting magic, or
used for unspecified ceremonial purposes. Several charmstones of a variety of
forms were found in a 2000 year-old grave at Emeryville. In addition to charmstones, several
beautifully shaped and polished stone pendants were recovered.
Shell pendants cut from abalone shells, and olivella beads
(made from the shell of a small sea snail) were found at Emeryville almost exclusively in graves. Shell pendants were
made in a variety of forms. Most spectacular are several large disks, incised on the shiny
nacreous face with a series of concentric rings. A number of teardrop or rectangular
forms also were decorated with lines of incised dots. Since no unworked abalone shell
was found at Emeryville, it is clear that abalone ornaments were arriving at the site ready-made. They likely were acquired in trade with coastal
people of the San Francisco Peninsula or Marin. The source of olivella beads is less
clear. Some, at least, may have
been made at Emeryville. Both whole shell beads created by grinding or cutting off the
tip of the shell spire, and fraction beads are present. Fraction beads are produced by
cutting an oval or round out of the side of the snail shell. The round is then smoothed by
chipping or abrasion and centrally perforated. Both beads and pendants probably were
strung on cord as necklaces, and also sometimes attached to clothing or headdresses.
Shell ornaments and beads were the items most commonly found in graves. The preferred
styles of beads--very subtle shifts in form--changed over time, and have been found to be
sensitive time markers. Groups of beads found in graves can be assumed to date to a
single time period, and thus are useful in characterizing the stylistic preferences of a
single time period. Other artifacts in the grave or the stratum then can be linked with
these characteristic beads. This is useful in identifying strata of similar periods elsewhere
in the site or at other sites.
The wide variety and huge quantities of animal bone at
Emeryville indicates that its people were very successful hunters. There is relatively little evidence of specific hunting
and fishing techniques in the tool kit, but the bone assemblage testifies to a wide variety
of hunting and fishing strategies. Early in the site's occupation, darts or spears with
chipped stone tips probably were used. By the time of the last occupation of the site, a
transition had been made to the bow and arrow, as indicated by the advent of small
projectile points. One item in the bone tool assemblage was identified as a harpoon toggle
on the basis of ethnographic analogy. Certainly the people of Emeryville possessed the
technology to capture large sea mammals and fish, but we have little direct evidence of
what that technology was. Whalebone is present in the site, but there is no evidence that
Emeryville people had the technology to capture whales; it is assumed that they simply
took advantage of occasional beachings. The large number of bat ray specimens in the
assemblage suggests that the Emeryville people used nets or weirs for fishing, although
there is no direct archaeological evidence of this technology. Some of the many bone tools at the site
may have been used in the production of nets or woven traps.
No archaeological evidence of structures was found in the
midden at Emeryville. Some archaeologists maintain that this indicates that people did not live at the site and that it
was used only for ceremonial purposes. Based on the volume of food debris and numbers
of discarded tools in the massive midden, this seems improbable. The ethnographic
record suggests that Emeryville houses would have been simple poles covered and tule
mat structures. It is likely that evidence of such structures, such as postholes and hard-packed earth housefloors, simply did not preserve in
the soft, damp midden of the site. Excavation did reveal hearth features, rings and clusters of rock, and numerous
lenses of ash and charcoal, indicative of cooking.
View photos of artifacts
recovered from the Emeryville Shellmound in 1999. For more detail on this topic, see
the technical report, Emeryville
Shellmound, 1999.
