A 1,350-year-old Egyptian weaving before dating...
...and after (Courtesy Marvin Rowe)
Posted on 12/24/2010 6:51:46 AM PST by SunkenCiv
Over the past 20 years, chemist Marvin Rowe of Texas A&M University has developed a nondestructive method for carbon dioxide extraction. In his process, an object is placed in a vacuum chamber and a supercritical fluid -- a hybrid gas/liquid -- is applied as a solvent (as in dry cleaning). Next, Rowe passes plasma -- an "electrically excited ionized gas" -- over the artifact, which selectively strips carbon from the sample. "It's essentially like slowly burning the sample, so we can just oxidize a little off the surface and collect that carbon dioxide," explains Rowe. This year he further refined the method so it will work on objects coated in sticky hydrocarbons, such as the resins that cover Egyptian mummy gauze.
Thus far, he's dated samples of wood, charcoal, animal skin, bone from a mummy, and ostrich eggshell... R. E. Taylor, a radiocarbon expert at the University of California, Riverside, says Rowe's technique may have limitations, as items older than 10,000 years will have impurities that the technique may not be able to purge. Archaeologists, meanwhile, are hailing the discovery as one of the most important in decades, particularly for issues surrounding the repatriation of human remains from Native American burials, which modern tribes don't want to see harmed.
Rowe's refinement of carbon dioxide extraction dovetails with an update to the radiocarbon calibration curve, which increases the accuracy of radiocarbon dating by accounting for past fluctuations in carbon 14. According to researchers at Queen's University of Belfast, the new curve doubles the accuracy of dating as well as the age of artifacts on which it can be used, from 25,000 to 50,000 years.
(Excerpt) Read more at archaeology.org ...
A 1,350-year-old Egyptian weaving before dating...
...and after (Courtesy Marvin Rowe)
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Cool Aggie science ping.
Thx!
I had this guy for Organic when I was at A&M!
At last!
Hopefully it’s more accurate.
Cool!
“This is my weapon, this is my gun...”
Shroud time...just do it and do it right.
RC dating has a range of error, which some (falsely) claim make it unreliable. There are also results which get thrown out because they don’t conform to preconceived notions, e.g. the contents of Ramses II’s canopic jars, his internal organs IOW, which dated over 700 years younger than the conventional pseudochronology sez they are (Velikovsky reconstructed the actual date, in 1945, before RC dating was figured out), or e.g. the wood from the Ulu Burun wreck, which was originally trumpeted as nailing the exact date of the shipwreck, until it was realized that it actually did the exact opposite.
It’s already been done right.
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