Obsidian dating Adult avatars and chatbots

Sourcing obsidian--that is to say, discovering where the raw stone from a particular obsidian artifact came from--is typically conducted through trace element analysis.

Although obsidian is always made up of volcanic rhyolite, each deposit has slightly different amounts of trace elements in it.

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Comparisons are made between the results of obsidian hydration and other dating methods.

We compare over 230 obsidian hydration readings from 30 individual site components from the Southern Nasca Region (SNR) with independent age estimates based on radiocarbon dates and temporally diagnostic artifacts.

For information on dating obsidian , see the article on obsidian hydration. Obsidian-hydration dating: Its past, present, and future application in Mesoamerica. Kuzmin YV, Speakman RJ, Glascock MD, Popov VK, Grebennikov AV, Dikova MA, and Ptashinsky AV. Obsidian use at the Ushki Lake complex, Kamchatka Peninsula (Northeastern Siberia): implications for terminal Pleistocene and early Holocene human migrations in Beringia.

See the History of Glass Making, if that's what interests you.

Two parallel cuts are made into the edge of the artifact using a lapidary saw equipped with 4-inch diameter diamond-impregnated .004″ thick blades.

These cuts produce a cross-section of the artifact approximately one millimeter thick which is removed from the artifact and mounted on a petrographic microscope slide with Lakeside thermoplastic cement. A New Dating Method Using Obsidian: Part I, The Development of the Method. The effects of these variables have often been summarized and will not be discussed further here (Michels and Tsong 1980; Friedman and Obradovich 1981; Freter 1993; Hull 2001; Stevenson et al., 1993, 1998, 2000; Friedman et al. 1999, Ridings 1996; see Skinner and Tremaine 1993 for additional references). Once a hydration layer has been measured, it can be used to determine the relative ages of items or, in some circumstances, can be converted into an estimated absolute age. For more rock science on the substance, see the geology entry for obsidian. INTRODUCTION | PREPARATION METHODS | REFERENCES The obsidian hydration dating method was introduced to the archaeological community in 1960 by Irving Friedman and Robert Smith of the U. When a new surface of obsidian is exposed to the atmosphere, such as during the manufacture of glass tools, water begins to slowly diffuse from the surface into the interior of the specimen. Scholars identify the chemical fingerprint of each deposit through such methods as X-ray fluorescence or neutron activation analysis and then compare that to what is found in an obsidian artifact.

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