Costanza, a renowned French jewelry designer born in 1926 and who passed away in 2023, emerged as a leading figure in avant-garde jewelry during the 1970s. Bold and visionary, she collaborated with prestigious fashion houses such as Pierre Cardin and Hermès, bringing a distinctly modern and sculptural approach to their collections. A true pioneer in the use of synthetic materials, Costanza explored the aesthetic potential of altuglas—a thermoformable plastic—to create striking, architectural pieces that were as visually powerful as they were comfortable to wear. Her most iconic works include the "Grand Ovale" ring (1967) and the "Nestor" pectoral (1970), which exemplify her mastery of form and innovative spirit. Her creations, celebrated for their artistic and technical audacity, are preserved today in the collections of the Musée des Arts Décoratifs (MAD) in Paris, solidifying her legacy in the history of contemporary jewelry design.