Time of Augustus, Tessera Nummularia, 25 BC; (Ivory, hexagon shaped, mm 37 x 11); Side 1) - ERASTVS; side 2) - IVLI; side 3) - palm branch; side 4) - SP ID NOV; side 5) - IMP (ligate) C IX M SIL; side 6) - trident.
Latin transcription: Erastus / Iuli / id(ibus) nov(embris) / Imp C(aesare) IX M(arco) Sil(ano).
English translation: 'Erastus (servant) of Julian family, checked (the contents of the coins bag) in November, under the consulship of Marcus Silanus with Emperor Augustus in his ninth salutatio imperatoria'.
Small chip on loop.
'Tessera nummularia' are seals which were attached to a coin bags (folles), certifying that the coins within were of the right number and genuine, by a mint official called a 'nummularius'.