Large Antique Pietra Dura brooch in a gold frame. Pietra dura (translation hardstone) refers to a Florentine mosaic technique that is a descendant of the Roman opus sectile mosaic style. In this technique, carefully sawn pieces of gemstones are fitted together like a jigsaw puzzle to form an image. The pietra dura technique blossomed during the Renaissance and revived in the 19th century.
