A typical Art Nouveau design in this rose gold brooch by the Murrle Bennett company, a collectible mark in business n Pforzheim and London from     1884-1916.  The brooch is stamped 9ct on the reverse together with the MB & Co logo and further marked "Prov. Patent.  Fastening by way of a hinged pin and C scroll catch.
 
Dimensions
W 0.88 in. x D 0.32 in. x L 1 in.
W 22.36 mm x D 8.13 mm x L 25.4 mm