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
Beryllium copper powdered steel or iron seats & guides. The softer BeCu reduces valve wear and increases valve life. Beryllium copper (C17200 & C17300) is an age-hardening alloy which attains the highest strength of any copper base alloy. It may be age hardened after forming into springs, intricate forms or complex shapes. It is valued for spring properties, corrosion resistance, stability, conductivity, and low creep. Tempered beryllium copper is C17200 & C17300 that has been age hardened and cold drawn. No further heat treatment is necessary beyond a possible light stress relief. It is sufficiently ductile to wind on its own diameter