MCI Project Summaries 2008 - Smithsonian Institution

IRMS #: 0024
PIs: Mary Ballard and Ed Vicenzi (MCI)
Smithsonian Initiative: Valuing World Cultures
Title: Isotopic evaluation of the Midas
textiles
MCI is collaborating with University of
Pennsylvania researchers on the analysis
of 11 textile samples from the prominent
Tumulus MM at Gordion, Turkey—
widely considered to be King Midas’s
tomb. Despite the tomb’s pristine and
methodical excavation, no gold was ever
found inside it—there was bronze, iron,
and exquisite inlaid furniture, but no
gold. At first glance, the textiles were
unimpressive—either degraded clumps
or small fragments in which uneven weaving and knots were hardly of regal quality. At high
magnification, the fibers were found to be hollow—with no organic material left. What appeared
as yarns seemed simply the artifact of a uniform coating, entirely hollow, as seen with
SEM/EDS, and composed of iron. After washing off microbial debris with solvents, an organic
infrared spectrum was taken. It matched “Goethite” a gold-colored iron oxide (α- FeOOH),
which in turn matched a recently published textile study. Various innovative analytical systems
were employed, unsuccessfully, to prove the link between the Tumulus MM textiles and
Goethite. The samples were subsequently analyzed with a TerraSpec VIS/NIR spectrometer
which gave a definitive peak at 760 nm, in the near infrared, and proved the close similarity of
Goethite in the Midas sample, its match to the modern polyester coated linen, and a known
reference spectrum. Other fragments from the tomb, once thought to be green because of their
proximity to the copper and bronze artifacts, have been proved to be composed of indigo and
goethite—a sophisticated mixing of organic and inorganic chemistry. The Lydian king buried so
long ago reigned over a kingdom filled with very capable scientists and textile technologists.
IRMS #: 0025
PIs: Dennis Whigham (SERC) and Ryan King (Baylor U.)
Smithsonian Initiative: Understanding and Sustaining a Biodiverse Planet
Title: Influence of riparian vegetation communities on stream food web structure
Project Summary: This study is focused on how riparian vegetation communities influence
stream food web structure, as inferred using hydrogen, carbon and nitrogen stable-isotope ratios.
Using samples collected across different wetland geomorphic settings (ecosystems), we will
determine if different riparian wetland vegetation along headwater streams differentially support
stream food webs. The study will help quantify the hypothesized linkage between uplands,
wetlands, and streams in supporting juvenile salmon production. This information will be an
important first step for regulators and managers to assess the ecological consequences of
development activities in the headwater regions of watersheds on the Kenai Peninsula.
33