This press release is a popular account of some of the archaeometric work being undertaken at the National Institute of Standards and Technology (NIST). Lead isotope ratio analysis is being used to trace the origin of bronze artifacts and to verify their authenticity. A current project focusing on over 300 bronze objects in the Smithsonian's Arthur M. Sackler Gallery of Oriental and Near Eastern Art is highlighted. The bronze vessels in the collection are from the Shang, Western Zhou, and Eastern Zhou dynasties. Emile Joel, a chemist at the Smithsonian's Conservation Analytical Laboratory (CAL), which is collaborating in the project with NIST, is quoted as saying that Chinese craftsmen added lead to bronze alloys. Linus Barnes of NIST is also quoted. The technique is based on the observation that ratios of isotopes of lead to one another yield a unique signature which identifies a particular lead mine location. Thus, artifacts with similar lead isotope ratios can be sometimes attributed to a single production center. When combined with art historical or trace element studies, the reliability of a particular source attribution is increased further. A mass spectrometer is used to determine isotopic concentrations. The News Release concludes with reference to some other projects currently underway and in the planning stages.