File:Roman knee brooch (FindID 387840).jpg

English: Roman cast copper alloy knee brooch, 2nd-3rd century. The pin is missing; the spring would have been held on a rod between two lugs (now broken) on the back of the headplate - the rod and two turns of the spring are present but detached. The large flat hemispherical headplate has moulded decoration of three semicircles fanning out from the top of the bow. The bow is P-shaped in profile and D-shaped in section; it tapers gently then terminates in a bulbous foot. The damaged catchplate extends from the foot to the start of the arched upper bow. Fine light brown-green patina. Length 30.5mm, width across head 13.4mm, width across top of bow 7.3mm, width across foot 5.2mm, thickness across bow 4.2mm, thickness as curved 11.1mm, weight 4.71g. The brooch is characteristic of Bayley and Butcher's Type 171 with its semi-circular head concealing two lugs to hold the spring in place (Bayley and Butcher 2004, p. 180). However, the decoration on the headplate is unusual. Type 171 knee brooches are found at both military and civilian sites in Britain.