Prehistoric rinds can vary from less than 1 micron (µm) to more than 50 µm, depending on the length of time of exposure.By measuring the thickness you can easily determine if one artifact is older than another (relative age).When a fresh surface of obsidian is exposed to the atmosphere, as when it is broken to make a stone tool, more water is released and the rind begins to grow again.That new rind is visible and can be measured under high-power magnification (40-80x).Unpublished Master's Thesis, Department of Chemistry, University of Missouri, Columbia, Missouri. Archaeology Press, Simon Fraser University, Burnaby, British Columbia. International Association for Obsidian Studies Bulletin 7:4-6. BIAGI, PAOLO, ANNA MARIA DE FRANCESCO, and MARCO BOCCI (2007) New Data on the Archaeological Obsidian from the Middle-Late Neolithic and Chalcolithic Sites of the Banat and Transylvania (Romania). Thesis, Department of Archaeology, University of Glasgow, Glasgow, Scotland. In Proceedings of the Society for California Archaeology 7-223. In Proceedings of the Society for California Archaeology -76. (2000) Bone Cave: A Special-Use Site in the High Lava Plains. SKINNER (2003) Investigation of Assemblage Structure and Variation at CA-MNO-566 Near Bridgeport, Mono County, California. International Association for Obsidian Studies Bulletin 46:7-18. Obsidian Use in the Willamette Valley and Adjacent Western Cascades of Oregon. BELLOT-GURLET, LUDOVIC, THOMAS CALLIGARO, OLIVIER DORIGHEL, JEAN-CLAUDE DRAN, GERARD POUPEAU, and JOSEPH SALMON (1996) Excavations at Pestera Ungureasca (Caprelor) (Cheile Turzii, Petresti de Jos, Transylvania) 2003-2004: A Preliminary Report on the Chipped Stone Assemblages from the Chalcolithic Toarte Pastilate (Bodrogkeresztur) Layers. In A Short Walk Through the Balkans: The First Farmers of the Carpathian Basin and Adjacent Regions, edited by Michela Spataro and Paolo Biagi, pp. Trieste, Societ� per la Preistoria e Protostoria della Regione Friuli-Venezia Giulia Quaderno 12, 2007. THATCHER, CRAIG SKINNER and BRIAN WICKSTROM (2009) Obsidian Hydration, Cut Sample Selection, and Technological Aspects of Debitage. (1941) Lithic Landscapes and Taskscapes: Obsidian Procurement, Production and Use in West Central Sardinia, Italy. Hunter-Gatherers, Mobility, and Obsidian Procurement: A View from the Malheur Headwaters, Northeast Oregon. Unpublished Master's Thesis, Interdisciplinary Studies, Oregon State University, Corvallis, Oregon. In Proceedings of the Society for California Archaeology -87. FRAHM, ELLERY (2013) Obsidian Sourcing, Dating, and Technology in the New Word: Readings from American Antiquity and Latin American Antiquity (1962-2012). By targeting protected fissures not exposed to surface weathering effects, a consistent series of hydration readings has allowed age determinations of an obsidian mine site where the radiocarbon dates are unreliable, or fall within the undateable “modern” of the last 300 years.
Finite difference modeling and essential assessments of the novel SIMS-SS (surface saturation) phenomenological method produce a sound basis for the new diffusion age equation and provides promising results.Over time, water slowly diffuses into the artifact forming a narrow "band," "rim," or "rind" that can be seen and measured with many different techniques such as a high-power microscope with 40-80 power magnification, depth profiling with SIMS (secondary ion mass spectrometry), and IR-PAS (infra red photoacoustic spectroscopy).In order to use obsidian hydration for absolute dating, the conditions that the sample has been exposed to and its origin must be understood or compared to samples of a known age (e.g.About fifty years ago Friedman and Smith  recognized the obsidian hydration phenomenon and proposed an empirical dating method based on the conversion of the optically measured hydration depth to an absolute age.They and subsequent researchers developed distinct versions of obsidian hydration method consisting of both empirical rate and intrinsic rate development, thus refining the method.Obsidian hydration dating (or OHD) is a scientific dating technique, which uses the understanding of the geochemical nature of the volcanic glass (a silicate) called obsidian to provide both relative and absolute dates on artifacts.Obsidian outcrops all over the world, and was preferentially used by stone tool makers because it is very easy to work with, it is very sharp when broken, and it comes in a variety of vivid colors, black, orange, red, green and clear.The documents available here are fully searchable from within Adobe Acrobat Reader. Archaeology Press, Simon Fraser University, Burnaby, British Columbia. (1958) Bremsstrahlung Ratio Technique Applied to the Non-Destructive Energy-Dispersive X-Ray Fluorescence Analysis of Obsidian. JOHNSON (1995) The Obsidian Cliff Plateau Prehistoric Lithic Source, Yellowstone National Park, Wyoming. Unpublished Master's Thesis, School of Archaeological Studies, University of Leicester, England. Nuclear Instruments and Methods in Physics Research B 24-150. This online library replaces the old IAOS Obsidian Bibliography, a pre-WWW resource that was rendered obsolete by the World Wide Web and that has now been retired. AMBROSE (2008) Ancient Trade Routes for Obsidian Cliffs and Newberry Volcano Toolstone in the Pacific Northwest. International Association for Obsidian Studies Bulletin 11:9-10 DAVIS, LESLIE B, STEPHEN A. Selections from the Division of Cultural Resources No. Dissertation, Department of Anthropology, University of California, Berkeley, California. (2002) Geochemical Characterization of Obsidian Subsources from the Coso Range, California Using Laser Ablation Inductively Coupled Plasma Mass Spectrometry as a Tool for Archaeological Investigations. : Landscape and Geochemical Considerations and Their Archaeological Implications. LIRITZIS, IOANNIS and NIKOLAOS LASKARIS (2011) Nano- and Micro-Scale Resolution in Ancient Obsidian Artefact Surfaces: The Impact of AFM on the Obsidian Hydration Dating by SIMS-SS. as a result of radiocarbon dating of associated materials).Their initial work focused on obsidians from archaeological sites in western North America.