Authentic vintage Italian brooch manufactured by the historic goldsmith UnoAerre in Arezzo, Italy. The reverse side features a clear "ITALY" stamp, the official UnoAerre factory registration hallmark "1 AR", and a "750" stamp confirming solid 18-karat yellow gold purity. The brooch features a classic three-knuckle pin hinge and a fully functional rotating C-clasp safety catch mechanism. The outer border displays intricate openwork gold filigree wirework. The structural integrity is in excellent vintage condition with no broken solder joints. Authentic vintage Italian brooch manufactured by the historic goldsmith UnoAerre in Arezzo, Italy. The reverse side features a clear "ITALY" stamp, a "750" stamp confirming solid 18-karat yellow gold purity, and the official factory registration hallmark "1 AR" stamped directly to the left of the pin hinge assembly. The brooch utilizes a three-knuckle pin hinge and a fully functional rotating safety catch mechanism, which also features its own corresponding tiny gold purity hallmark stamp inside the channel. The outer frame features intricate, openwork gold filigree wirework. The piece is in excellent structural vintage condition with no broken joints.