The distinctive shape of Nagau helmets represented the ferocity and might of the Etruscan army. Memories of these soldiers lived on for centuries after the Etruscan metalsmiths stopped producing them, as evidenced by an eastern Hungarian Celtic tetradrachm (ca. 2nd century BCE) that depicts a horseman wearing one of these helmets and holding a torc, a symbol of power. The item has undergone X-ray fluorescence analysis to confirm the metallurgical content suggesting its ancient origin and lack of modern trace elements.
Reference: Cf. a pilos helmet in Berlin, illustrated in Antikenmuseum Berlin (Berlin, 1988), no. 1 on pp. 80-81.