And the ancillary part of that is it’s non-destructive.”That’s important to Nancy Akins, a research associate with the Office of Archaeological Studies, who in February was having a bison tooth and sheep bone tested by “Marvin’s Machine.” The items were excavated from the site of a rock shelter in Coyote Canyon north of Mora.“It could be 500 years old or it could be 5,000 years old,” she said of the bison tooth, the result allowing her to complete her report of the site that she’s determined to have been used by humans as a hunting outpost starting 1,700 years ago.“I’m just waiting on the dates, because it’ll change everything if we get dates where I can actually say, ‘OK, that’s what the sheep bones date to and that’s what the bison dates to.’ It tells us an awful lot about how they were using the land on the east side of the Sangre de Cristos.”Because a lot of that part of New Mexico is private property or under land grants, such finds as the one in Coyote Canyon are rare, she said.“Unless there’s a road or something, we don’t have any information at all.
This is one of the very, very few sites in Mora County that have been excavated,” she said of the site reported by the state Department of Transportation.
The machine is used to date artifacts by doing minimal damage to the sample. — The contraption he built looks a little like something you might see from “The Nutty Professor.”But Marvin Rowe is no nut.
(Eddie Moore/Albuquerque Journal)Marvin Rowe, a scientist at the New Mexico Office of Archaeological Studies, adjusts the Low Energy Plasma Radiocarbon Sampling device he built to date artifacts with minimal damage. That machine he built, and what it’s used for, helped Rowe win the prestigious Fryxell Award for Interdisciplinary Research from the Society of American Archeology two years ago.“We call the process Low Energy Plasma Radiocarbon Sampling,” said New Mexico’s state archeologist Eric Blinman, who credits Rowe with inventing the process.
Blinman said the process’s capability to date very small samples would allow, for instance, determination of the age of the ink on a Chinese text written on bamboo.
(Eddie Moore/Albuquerque Journal)One of a kind Rowe won his Fryxell Award “based in his prominent role in developing methods for rock art dating and minimally-destructive dating of fragile organic artifacts,” as well as his scientific analysis, scholarship and student training, according to the SAA website. Rowe and two colleagues at Texas A&M’s Department of Chemistry built the first plasma dating machine in 1990 while exploring ways to extract organic carbon from pictograph samples.“Other people have been successful dating charcoal paintings,” Rowe explained.Besides the body of the Iceman, numerous pieces of equipment of the Iceman and other materials associated with the finding place were recovered (Lippert, 1992; Bagolini et al., 1996).A small but representative fraction have now been radiocarbon dated at three different AMS laboratories.“But, in the United States at least, most of the paintings are not charcoal.Most of them that I’ve encountered are inorganic pigments and that’s where the importance of the small sample comes in.”Blinman adds that, under the best of circumstances, standard radiocarbon dating requires 30 milligrams of carbon.They have to use acids and, within that process, you lose a large part of your sample and you destroy it,” Blinman explained.“But we now have the ability to date incredibly small amounts of carbon – 40-100 millionths of a gram – and that is the real revolutionary aspect of this.He showed a picture of a turkey feather that had been tested and hardly looks ruffled.“The experience of the artifact is no different than your body temperature or, worst case, Phoenix on a summer day,” he said.Blinman explained that Rowe’s alternative process is based on plasmas – ionized gas made up of groups of positively and negatively charged particles, and one of the four fundamental states of matter, alongside solid, liquid and gas.Plasmas are used in television displays and in florescent lights, which use electricity to excite gas and create glowing plasma.