could this perhaps have been found at the facility the US helped build?
from new york times: The global nuclear monitoring agency deepened suspicions on Thursday about Iran’s nuclear program, reporting that inspectors had discovered new traces of highly enriched uranium at an Iranian facility.
Inspectors have found such uranium, which at extreme enrichment levels can fuel bombs, twice in the past. The International Atomic Energy Agency concluded that at least some of those samples came from contaminated equipment that Iran had obtained from Pakistan.
But in this case, the nuclear fingerprint of the particles did not match the other samples, an official familiar with the inspections said, raising questions about their origin.