Elizabeth Wuellner | University of North Carolina at Chapel Hill (original) (raw)
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Papers by Elizabeth Wuellner
Journal of Archaeological Science: Reports, 2023
Sourcing archaeological amber has hitherto been limited by a reliance on chemical techniques that... more Sourcing archaeological amber has hitherto been limited by a reliance on chemical techniques that require some degree of destructive sampling. The majority of amber artifacts are friable, weakened after millennia spent unprotected from environmental stressors, and as such are especially vulnerable during analysis or even sampling. Here, we assess the capability of an entirely nondestructive analytical technique-Diffuse Reflectance Infrared Spectroscopy (DRIFTS)-to scientifically identify archaeological Baltic amber. Using a reference collection of geological amber specimens, our direct comparison of DRIFTS spectra to those collected via conventional transmission FTIR, which necessitates destructive sampling, demonstrates the validity of the new technique. Thirteen beads from the archaeological site of Dura-Europos in Syria were subsequently analyzed using DRIFTS alone. Five of the beads showed spectral features indicative of Baltic amber, whereas the others were too degraded to yield diagnostically measurable spectra. Our study thus confirms the capability of the DRIFTS technique to analyze whole, untreated amber artifacts when their integrity is of high concern. Furthermore, our results indicate a previously unestablished connection between Dura-Europos and northern Europe during the first two centuries CE through long-distance exchange networks stemming from the Mediterranean basin.
Journal of Archaeological Science: Reports
Here we introduce a set of well-characterized historical brick and geological specimens intended ... more Here we introduce a set of well-characterized historical brick and geological specimens intended to aid the calibration of portable XRF (pXRF) instruments for archaeological ceramics. Known as the BRICC Bricks and Rocks for Instruments Ceramic Calibration sets, each of the ten matched sets consists of 20 specimens mounted in epoxy discs: 12 bricks and 8 geological specimens to use for calibration. Additionally, a certified reference material a shale standard measured by 85 labs is included with each set to assess the resulting accuracy, and a high-purity silica blank is included to check for spectral interferences or other calibration issues. The BRICC sets provide an open-source alternative to pXRF calibration approaches that are proprietary, were devised for oil shales instead of ceramics, and/or rely on expensive and often unavailable certified standards. A set can be tested at Yale or borrowed following loan policies of the Yale Peabody Museum. Publishing all information for the historical bricks and geological specimens from their origins to the data used to derive the recommended values fulfills the requirements of scientific transparency. Ultimately, these sets are intended and designed as a means to meet and exceed experts practices regarding accuracy, reproducibility, and scientific transparency when analyzing ceramics using pXRF and (2) to reduce siloed production of knowledge within established laboratories and, hence, facilitate integration of more diverse perspectives into elemental studies of archaeological ceramics.
Journal of Archaeological Science: Reports, 2023
Sourcing archaeological amber has hitherto been limited by a reliance on chemical techniques that... more Sourcing archaeological amber has hitherto been limited by a reliance on chemical techniques that require some degree of destructive sampling. The majority of amber artifacts are friable, weakened after millennia spent unprotected from environmental stressors, and as such are especially vulnerable during analysis or even sampling. Here, we assess the capability of an entirely nondestructive analytical technique-Diffuse Reflectance Infrared Spectroscopy (DRIFTS)-to scientifically identify archaeological Baltic amber. Using a reference collection of geological amber specimens, our direct comparison of DRIFTS spectra to those collected via conventional transmission FTIR, which necessitates destructive sampling, demonstrates the validity of the new technique. Thirteen beads from the archaeological site of Dura-Europos in Syria were subsequently analyzed using DRIFTS alone. Five of the beads showed spectral features indicative of Baltic amber, whereas the others were too degraded to yield diagnostically measurable spectra. Our study thus confirms the capability of the DRIFTS technique to analyze whole, untreated amber artifacts when their integrity is of high concern. Furthermore, our results indicate a previously unestablished connection between Dura-Europos and northern Europe during the first two centuries CE through long-distance exchange networks stemming from the Mediterranean basin.
Journal of Archaeological Science: Reports
Here we introduce a set of well-characterized historical brick and geological specimens intended ... more Here we introduce a set of well-characterized historical brick and geological specimens intended to aid the calibration of portable XRF (pXRF) instruments for archaeological ceramics. Known as the BRICC Bricks and Rocks for Instruments Ceramic Calibration sets, each of the ten matched sets consists of 20 specimens mounted in epoxy discs: 12 bricks and 8 geological specimens to use for calibration. Additionally, a certified reference material a shale standard measured by 85 labs is included with each set to assess the resulting accuracy, and a high-purity silica blank is included to check for spectral interferences or other calibration issues. The BRICC sets provide an open-source alternative to pXRF calibration approaches that are proprietary, were devised for oil shales instead of ceramics, and/or rely on expensive and often unavailable certified standards. A set can be tested at Yale or borrowed following loan policies of the Yale Peabody Museum. Publishing all information for the historical bricks and geological specimens from their origins to the data used to derive the recommended values fulfills the requirements of scientific transparency. Ultimately, these sets are intended and designed as a means to meet and exceed experts practices regarding accuracy, reproducibility, and scientific transparency when analyzing ceramics using pXRF and (2) to reduce siloed production of knowledge within established laboratories and, hence, facilitate integration of more diverse perspectives into elemental studies of archaeological ceramics.