ORNL/AARO 'Analysis of a Metallic Specimen' (2022).

Oak Ridge National Laboratory analysis (for AARO, contracted 2022) of the layered Mg-Zn / Bi-Pb 'Art's Parts' specimen. LA-ICP-MS and TEM found a magnesium matrix with ~2% zinc and banded layers where bismuth and lead are co-located in roughly 1:1 ratio, with columnar Mg grains perpendicular to the banding. Magnesium and lead isotopic compositions fall within terrestrial values; the Mg shows ordinary light/heavy isotope separation attributable to heat and mechanical stress during manufacturing. ORNL concluded the specimen is terrestrial and does NOT meet the theoretical requirements to function as a terahertz (THz) waveguide, because the bismuth is intermixed with lead and is highly nanocrystalline rather than single-crystalline single-layer. AARO's supplement: consistent with mid-20th-century Mg-alloy R&D; chain of custody unverifiable.