Fig 1.
Illustration of several flake attributes discussed here.
On the left is a schematic semispherical core used in the Dibble and colleagues glass experiments. On right is a schematic profile of the core through the point of percussion.
Fig 2.
Left, an example of a semispherical glass core from the Dibble and colleagues experiments with landmarks on the platform outline. Above right, those same landmarks plotted in XY space. Below right, the core edge after fitting a polynominal curve to the XY landmarks.
Fig 3.
Distribution of estimated PSIA based on the Dibble glass flakes.
Fig 4.
PW, PD, EPA and weight against the estimated PSIA based on the Dibble glass flakes.
Fig 5.
AOB against the estimated platform surface interior angles based on the Dibble glass flakes.
Fig 6.
The actual platform depth to platform width data from the Dibble glass core flakes and the estimated platform width using the average platform surface interior angle calculated previously.
Fig 7.
A comparison of the estimated platform surface interior angle, this same angle as calculated from caliper measurements, and this same angle measured with a goniometer.
All measures are in degrees.
Fig 8.
The distributions of platform surface interior angle as directly measured with a goniometer and as calculated from caliper measurements.
Fig 9.
Distribution of PSIA in the Campagne data set color coded by percussion type.
Fig 10.
PSIA as a function of platform width, platform depth, and EPA in the experimental flake collection.
Color coding is the same as in Fig 8.
Fig 11.
Distribution of platform surface interior angle in the MPI flakes dataset as measured by a digital goniometer.
Fig 12.
Platform depth to platform width including beveled flakes (red) and non-beveled flakes (black) (top).
Estimated points in blue are the same beveled flakes but with the platform depth predicted using the average PSIA and their actual platform width. At the bottom, the actual flake weight is compared to the predicted flake weight based on an EPA-PD model for non-beveled flakes (points in black). The predicted weight using the actual (w/o PSIA) and the modeled (with PSIA) platform depths for the beveled flakes are then plotted as well in red and blue respectively.