Update: Free Obsidian Source Characterization and Non-Destructive Artifact Sourcing
I've assembled a reference collection of obsidian specimens that I've nicknamed the "MinOAN" (Minnesota's Obsidian of Anatolia and the Near East) collection, but I have started expanding the collection beyond these areas. The collection is constantly growing, and it contains specimens from a variety of countries and regions, including (at present):
• Turkey: over 100 collection areas in Anatolia and Cappadocia
• Caucasus: Armenia, Azerbaijan, Georgia, the Kabardino-Balkar Republic
• Aegean islands and coasts: western Turkey coast, Milos island
• East African Rift sources: Ethiopia, Eritrea, Kenya, Tanzania
• Central Mediterranean: Lipari island
• Arabian Peninsula: Yemen
• Tibesti Mountains: Chad
• More countries and regions are on the way!
I am using my analyses of this collection to source artifacts from various archaeological sites. I have been asked to do obsidian artifact sourcing with various organizations and expeditions, including:
• Tell Mozan, Syria; International Institute for Mesopotamia Area Studies
• Centre for Archaeological Studies, Ilia Chavchavadze State University, Georgia
• Georgian National Museum, Tbilisi, Georgia
• Cadir Hoyuk, Turkey; Alishar Regional Project
• Domuztepe, Turkey; excavated by Stuart Campbell (Manchester) and Liz Caret (UCLA)
• Kenan Tepe, Turkey; excavated by Bradley Parker (Utah) and Lynn Swartz-Dodd (USC)
I'm characterizing the entire collection using electron microprobe analysis (also called electron probe microanalysis) in the University of Minnesota's Electron Microprobe Lab in the Department of Geology and Geophysics. Details about and reasons for my use of electron microprobe analysis can be found further down.
In addition to electron microprobe analysis, parts of the collection also have been or will be analyzed using: hand-held (portable) x-ray fluorescence (HH-XRF or pXRF), laboratory-based energy-dispersive x-ray fluorescence (ED-XRF), inductively coupled plasma-mass spectrometry (ICP-MS), Fourier-transform infrared spectroscopy (FT-IR), and/or instrumental neutron activation analysis (INAA). Geomagnetic measurements are also being taken.
In additional, I have a database of obsidian chemical characterizations from previously published studies.
The result is a rich data set for sourcing obsidian artifacts from Anatolia, Syro-Mesopotamia, and the entire Near East.
Using electron microprobe analysis, rather than mass spectrometry and neutron activation analysis, obsidian artifacts may be analyzed non-destructively. Whole artifacts can be analyzed, as shown above, without sampling so long as the artifact can fit through the airlock. Obsidian artifacts commonly have extremely smooth surfaces, so no polishing is necessary on many artifacts. There are no size effect in EMPA, unlike x-ray fluorescence, so obsidian fragments as small as a grain of sand could be accurately analyzed. There is no induced radioactivity, so analyzed artifacts are safe to handle afterward. There is no chemical alteration either. The only requirements are: (1) the artifact is clean and (2) a very thin carbon coat (roughly 0.00001-millimeters or 10-nanometers thick -- for comparison, green light has a wavelength of 500 nanometers) must be applied (for conductivity) and can be removed afterward.
Obsidian sourcing, or provenancing, can provide archaeologically useful information. For archaeological interpretation, it is an advantage to know precisely from where an artifact or its raw material originated. Information on the source of artifact material may be used to model trade networks and exchange spheres, and questions about the procurement and use of a material by past societies can be addressed. The mode of exchange by which the raw material or artifacts changed hands can also be explored. Trade implies contact, a source of cultural change as ideas are transmitted. In addition, the value of a material can be studied due to differences in the trade of commodities and prestige items. Issues that can be addressed extend beyond production and trade; matters of territory, access to resources, and technology can be delved into. The aim is to be able to make inferences about economic, political, and social structures of the cultures involved. Consequently, an artifact’s source, or its provenance, is as important as where it was unearthed.
I have been able to gather this collection thanks to many people and organizations, including (alphabetically):
• Tsegaye Abebe Adhana, Dipartimento di Scienze della Terra, Università degli Studi di Firenze
• Svetlana Akhundova, Geology Institute, Azerbaijan National Academy of Sciences
• Elizabeth Anthony (with student Jesus Velador), University of Texas-El Paso
• Ruben Badalyan, Institute of Archaeology and Ethnography, National Academy of Sciences, Armenia
• Amanuel Beyin, Interdepartmental Doctoral Program in Anthropological Sciences, State University of New York
• Giulio Bigazzi, Institute of Geochronology and Isotope Geochemistry, Italy
• M. James Blackman, National Museum of Natural History, Smithsonian Institution
• Michael Clynne, Volcano Hazards Team, United States Geological Survey (USGS)
• Magen Coleman, Archaeometry Laboratory, University of Missouri Research Reactor
• Irina Demetradze, Centre for Archaeological Studies, Ilia Chavchavadze State University, Georgia
• Gaye Demir, Stonex Mining Company, Turkey
• Tuncay Ercan, Mineral Research and Exploration Institute of Turkey
• Jeff Ferguson, Archaeometry Laboratory, University of Missouri Research Reactor
• Michael D. Glascock, Archaeometry Laboratory, University of Missouri Research Reactor
• Alain Gourgaud, Université Blaise Pascal - CNRS, Laboratoire Magmas et Volcans
• Leslie Hale, National Museum of Natural History, Smithsonian Institution
• Albert Harutyunyan, Geology and Exploration Technology, State Engineering University of Armenia
• Adem Kahraman, Mineral Stone/Ipekyolu Mining Industry and Foreign Trade Ltd, Istanbul, Turkey
• Sergey Karapetyan, Armenian Institute of Geological Sciences, National Academy of Sciences, Armenia
• François-Xavier Le Bourdonne, Institut de Recherche sur les Archéomatériaux, CNRS-Université Bordeaux
• James F. Luhr, National Museum of Natural History, Smithsonian Institution
• Givi Maisuradze, Institute of Geology, Georgian Academy of Sciences
• Khikmet Makhmudov, Baku State University & Geology Institute, Azerbaijan National Academy of Sciences
• Khachatur Meliksetian, Armenian Institute of Geological Sciences, National Academy of Sciences, Armenia
• George "Rip" Rapp, Department of Geological Sciences, University of Minnesota-Duluth
• Ming Hua Ren, Department of Geological Sciences, University of Texas-El Paso
• Nino Sadradze, Institute of Geology, Georgian Academy of Sciences
• Ivan Savov, School of Earth and the Environment, University of Leeds
• Robert L. Smith, United States Geological Survey (USGS)
• Ingrid Ukstins Peate, Department of Geoscience, University of Iowa
• John Whittaker, Department of Anthropology, Grinnell College
• Zehra Yegingil, Department of Physics, Cukurova University, Turkey
• University of Minnesota, Geology & Geophysics Teaching and Research Rock Collection
Update: Free Obsidian Source Characterization and Non-Destructive Artifact Sourcing
I am able to offer, at least for now, free non-destructive obsidian artifact sourcing using my "MinOAN" reference collection and electron microprobe analysis (and perhaps some of the other techniques I mentioned above). The obsidian artifacts must, of course, have originated in Turkey, Syria, Lebanon, Iraq, Georgia, Armenia, Azerbaijan, Iran, or elsewhere in the Near East for my collection to be useful. Because I am interested in expanding the collection to include more Old World (Asia, Europe, and Africa) obsidian sources, I am also willing to analyze geological sources samples too. For example, I am interested in gathering samples of east African (Ethiopia, Kenya, Tanzania) obsidian sources. If you are interested in obsidian source characterization and/or non-destructive artifact sourcing, please contact me. Any interested researchers should email me with the region involved, the approximate number of artifacts, research goals, etc. Researchers at any level, from graduate students to faculty, and in any country are welcome. Just send me an email if you are interested in participating or in further details about the source characterization and/or artifact sourcing.
