Copper-alloy, 15.64 grams, 81.94 mm. 1st century BC - 1st century AD. A large cast grinder bed with smoothed inner surface and single securing loop in the shape of a swan or duck head. The grinder was used to pulverise vegetable material such as woad in the preparation of dyes. Reference: Murawski, P.G. Benet's Artefacts of England and the United Kingdom, Ely, 2003 p.88 item I14-0401. Good very fine condition. Provenance: found Cambridgeshire, England.