Founded in Vicenza, the City of Gold in 1977, Roberto Coin jewelry celebrates the elegance of femininity, creativity and craftsmanship. From… Founded in Vicenza, the City of Gold in 1977, Roberto Coin jewelry celebrates the elegance of femininity, creativity and craftsmanship. From the "Venetian" collection, this delightful double-sided medallion necklace features a 10mm round black jade slice with sparkling diamonds on one side and a 10mm round mother-of-pearl slice on the reverse. Crafted in polished 18kt yellow gold and suspended from a rolo chain with a 2" extender. Made in Italy. Lobster clasp, Roberto Coin mother-of-pearl and black jade double-sided medallion necklace.