Over the past several years, rock
paintings from around the world have been radiocarbon dated based on
the assumption that they contained some organic material added to the
paint as binder or vehicle. The actual material present in the
most of these paints remains uncharacterized. To improve the
reliability of the radiocarbon results on rock painting samples, we
are preparing new paint using some possible binders (blood, bone
marrow, egg, plant juices and oils, etc.), applying the paints to
limestone and artificially aging them using heat and UV exposure.
We are currently using thermally-assisted hydrolysis/methylation-gas
chromatography-mass spectrometry (THM-GC-MS) to separate and identify
components in each binder that will hopefully be useful in then
identifying the unknown materials from authentic paintings.
Radiocarbon analysis on specific fractions of the organic matter will
also be carried out. Infrared spectroscopy (FTIR) has also been
used to characterize binders in historic artwork and has so far been
used to create a database of spectra for known rock painting
binders.This work has been supported with a Spring-Summer Award for Scholarly Activity from the Office of the Provost, Eastern Michigan University in 2002. University Faculty Research and Creative Activity Fellowships in 2004-2005, Fall 2006, and Winter 2009 have all supported work related to these projects. This is the central project for our group.
The interior of Little Lost
River Cave (10BT1) in southeastern Idaho is covered with a shiny,
hard, black coating that obscures the rock paintings located
there. Previous studies using stable isotope analysis and
plasma-chemical oxidation/AMS radiocarbon analysis
(Steelman et
al 2002 a&b) revealed
that the black material was likely of an animal origin and of an age
range between 1390 and 1040 cal BC. We have been studying the
coating qualitatively using pyrolysis- and THM-GC-MS and XPS, and
quantitatively using GC-MS of lipids to identify the nature of this
black residue. Several 
The
plasma-chemical oxidation method has been proposed as a
"nondestructive" technique for radiocarbon dating fragile
archaeological artifacts. We are investigating two questions
related to this process: (1) What changes are induced in the surfaces
of materials oxidized using the plasma method, and (2) is there an
appropriate pretreatment method to be used in conjunction with this
nondestructive dating process? Two graduate students have
worked to answer these questions: one developed a THM-GC-MS technique
to evaluate a new chemical pretreatment method, work that has been
carried on by several undergraduates, while the other used FTIR-ATR
to characterize changes in the functionalities at the surface of the
materials after they are exposed to the plasma treatment.
The fourth English colony in North
America, Maryland, had it's first capital at St. Mary's City from
1634-1696. This site, where religious freedom was first set
forth as law, is little known compared to Plymouth and Jamestown,
though the first Roman Catholic brick building in English America was
constructed there around 1667. Though only the foundations of
this structure remain, it must have been a massive building, with 25
foot high walls. The bricks used to build the chapel appear
different from other bricks used at the site. The chapel bricks
contain inclusions ranging in size and color, but are mostly black or
purple. We are undertaking an analysis of the bricks using
neutron activation analysis to compare the elemental compositions of
the bricks and the local St. Mary's County clays and using
petrographic analysis of thin sections to identify the mineral
inclusions in the bricks. SEM analysis of the nodules is also
planned. An
undergraduate student presented this work at the ACS National
Meeting in New Orleans in 2003. Travel grants from the EMU
College of Arts and Sciences, the EMU Chemistry Department, and the
Huron Valley ACS local section made her presentation possible.
Another undergraduate participated in the final stages of this
project and was a co-author on a publication. This work was
generously supported by the EMU Department of Chemistry through a
small grant for petrographic analysis and release time. This
project is now complete.
Soil samples are often retained during
an excavation for chemical analysis. Standard soil analyses for
agricultural purposes (such as soil phosphate, calcium and pH) can
also provide cultural information. Elevated soil phosphate
levels indicate human influence, and have been used to survey
possible archaeological sites before excavation. Preliminary
results of this project were presented at Pittcon 2003 in Orlando,
FL. Travel costs were defrayed by grants from the Josephine
Nevins Keal Fund and the College of Arts and Sciences. More
recently, the work was presented at the Inaugural Symposium for
Archaeological Sciences of the Americas in Tucson, AZ. This
work was incorporated into a class project for the CSIE Quantitative
Analysis laboratory in Winter 2008. Click
here for more information about the NSF-funded CSIE@EMU program.
Clinical
test strips, developed for urinalysis, have been suggested for rapid
analysis of rock paintings as a presumptive test for blood as a
binder. This long term study seeks to determine for how long blood
can be detected in rock painting samples, and if such tests are
appropriate. The preliminary publication for this project is in press
in the Proceedings of the International Symposium on Archaeometry
from Siena, Italy in 2008. The project is being carried out by Dr.
Daniel Fraser of Lourdes College.