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Hallmarks on silver objects can reveal much about the history of the piece. The name of the silversmith, the date of
manufacture, the quality of the metal alloy, as well as other information can be determined from the study of the
hallmarks. Because silver requires polishing to maintain its lustrous metallic surface, hallmarks tend to be worn away
over time resulting in the loss of important historical information. Utilizing Scanning Acoustic Microscopy, an image
of these vanished or illegible marks can be recovered. Two imaging modes are presented: time resolved surface wave
imaging of the near surface deformation in the silver and direct reflection from the silver back surface through the
remnant deformed silver. The contrast in these images is caused by variations in the ultrasonic velocities in the silver,
density changes, and acoustic attenuation due to the deformed silver microstructure. This technique is non-destructive
and non-contact.