Yetholm-type shield of dots. The artist could not hope to show the fine detail of a Yetholm-type shield, but the similarity is striking. The impressive shields would have indicated high social status. The shields are made of a copper alloy sheet about 0.6 mm thick. The alloy is a high-tin bronze: copper with 11-14% tin. They are round with a central domed boss created by hammering out from the back. The shield face is covered in raised ridges in concentric rings, each a couple of millimetres high. Between the ridges are rings of small hemispherical bosses about 4 mm across. Decoration was
Liberty Bell Museum found a considerably higher level of tin in the Liberty Bell than in other Whitechapel bells of that era, and suggested that Whitechapel made an error in the alloy, perhaps by using scraps with a high level of tin to begin the melt instead of the usual pure copper. The analysis found that, on the second recasting, instead of adding pure tin to the bell metal, Pass and Stow added cheap pewter with a high lead content, and incompletely mixed the new metal into the mold. The result was "an extremely brittle alloy which not only caused the Bell