VICENZA, Italy Vicenza is quaintly medieval at its center, a dense jumble of old butter-toned dwellings along narrow byways that occasionally give way to some of the Renaissances most elegant architecture, but these structures mask an industrial might that has made this small city Italys most productive capital of jewelry.We were born to do this kind of thing, said Roberto Coin, whose namesake company is one of Vicenzas most successful brands worldwide. We were born to create beauty, we were born to create new ideas. Its in our DNA. Its what we know how to do. Nearly 10 percent of the 100,000-plus population is employed in the jewelry sector, and teenagers can replace high school with jewelry studies at the Scuola dArte e Mestieri.The local legacy of jewelry-making predates even the cobbled streets: As far back as 600 B.C., the Vicentini were crafting clothing fasteners, called fibula, and other ornaments in bronze. But it was the 14th century, with its emphasis on craft and guilds (and a 1339 statute recognizing the goldsmiths fraglia, or guild), that crowned Vicenza as a prominent center of the jewelry arts and made its jewelers guild a political force among the nobles and merchants and of city society to this day.Vicenzas heart is the Piazza dei Signori, the bustling former Roman forum whose vast, stone-paved square is home to a centuries-old weekly market, a legion of aperitivo bars where evening crowds gather in this wine-loving town, and the storefronts of 10 independent jewelry businesses.There were 15 such shops on this piazza already in the 1300s; Soprana, the house that today has been at its piazza location the longest, was founded in 1770 by the family of jewelers that had made the famed precious crown for a statue of the Virgin Mary in the Church of St. Mary of Monte Berico nearby.The piazza is dominated by the slightly leaning (but still functioning) 14th-century Bissara clock tower; by two towering columns, topped by statues of Christ the Redeemer and the winged lion that symbolizes Venice, the lagoon city about 50 miles east that ruled Vicenza in the 15th century; and by the 16th-century Basilica Palladiana, with its stately double row of white marble arches by Andrea Palladio, the most influential architect of the Renaissance and Vicenzas most illustrious resident.Since 2014, the Basilica Palladiana has housed the Museo del Gioiello, promoted as the only jewelry museum in Italy and one of just a handful in the world, with a treasure box of an exhibition space designed by Patricia Urquiola. The museum is just completing what it says was the largest solo show ever dedicated to the artist and jeweler Gi Pomodoro, to be followed by an exhibition on crowns and tiaras. The display includes a rotating selection of jewelry from Vicenza and well beyond, including the Monte Berico crown; a Lalique 1890 bird brooch bedecked with a fistful of diamonds; and the Rosa dei Venti choker, set with panels of brightly colored gemstones, by the contemporary Milanese jeweler Giampiero Bodino.More than economic value, the museum provides cultural value, Alba Cappellieri, the director, said. The museum has enhanced the status of Vicenza as a jewelry capital, as it was intended to.Along with help from the city (which lends the Basilica Palladiana space) and some industry sponsors, the museum is funded primarily by the Italian Exhibition Group, which holds Vicenzaoro, the local jewelry trade show that attracts more exhibitors and attendees than any other in Italy. The twice-yearly event, scheduled to open Saturday, is held at the Fiera di Vicenza fairgrounds outside the city center. It drew more than 56,000 visitors in 2017, with 18,000 of them coming in January. By comparison, the January event this year attracted 23,000.Its not about being the largest fair, said Matteo Marzotto, the exhibition groups vice president. In 1836, his family began Marzotto Tessuti, now Italys leading producer of fabric and one of the reasons Vicenza is also a major supplier of textiles and fashion.What we want to be is the most beautiful fair, to offer three days of business when visitors can experience the Italian lifestyle, he said, pointing at the charms of the Piazza dei Signori, where he was sitting at El Coq, the citys Michelin-starred restaurant. (Growth, however, is still a priority, so with exhibitor and visitor numbers increasing, construction is scheduled to begin in 2019 on a fairgrounds pavilion of almost 540,000 square feet, a 20 percent expansion.)The crown of Our Lady of Monte Berico (1900), also at the museum. it is encrusted with peridot, diamonds, rubies, pearls, sapphires and amethyst, among other stones.Deeply linked to the territorys jewelry industry, Vicenzaoro is a particularly proud showcase for hometown brands such as Pesavento, Fope and Roberto Coin, although vendors come from around the world to sell.A city that suffered heavy bombings and deprivation during World War II (other Italians have taunted the townspeople as mangiagatti, or cat eaters), Vicenza never lost its connection to the goldsmiths art, and the economy revived in the 1950s and 60s as it combined its long jewelry tradition with industrial and technological innovation, helped along by American investment in the area, including the construction of a United States military base.By the 1970s, Vicenza was thriving amid a boom in European and American jewelry sales; the numbers of artisan ateliers surged, while factories turned out large quantities of jewelry and particularly of chains thanks to machines invented locally, said Cristina del Mare, a jewelry historian and one of the Museo del Gioiellos curators. This combination of skilled craftspeople and technology also established the city as the workshop for some of the best-known brands, including Gucci, Tiffany & Co. and Herms.Were very advanced technologically here, but what makes the difference is our manual skill, said Chiara Carli, who along with Marino Pesavento founded Pesavento 26 years ago at the Centro Orafa Vicentina, a complex on the city outskirts that houses 40 companies. The business creates dramatically Italianate jewelry with an emphasis on chains, combining the machine-made and 3-D-printed with the hand-assembled and finished.Pesavento is a majority female enterprise, unusual in this mostly male industry, with 26 women on the 40-person team running its workshops and offices. But in other aspects the brand is typical of Vicenzas jewelry companies: It is a family affair, with Ms. Carlis brother and twin sister working alongside her.Handcraft is still 80 percent of the work here, Ms. Carli said as she leaned over a woman in a blue smock who was delicately laser-soldering a silver chain, link by link. But Pesavento also represents the latest chapter of Vicenzas story: the adjustment since the 2008 downturn to a weakened Italian economy and difficult global market.Pesavento sells jewels of plated silver, not solid gold, and many are accented with the brands signature polveri di sogni, a dab of carbon microparticles that impart the shimmer of black diamonds at a much lower price. In general today, Vicenzas companies are marketing products that are less expensive than what they previously offered, but still reflect Italian style and know-how. With the crisis, we were obliged to become much more business-minded about what we do, Ms. Carli said.Globalization has killed Italy, said Mr. Coin, who says his export business remains strong despite competition from countries with lower production costs. The bigger got bigger; the smaller got smaller or disappeared. His business falls on the bigger side, while most of Vicenzas jewelry houses have been small, family-style operations. Mr. Coin estimates that there were around 5,300 jewelry businesses in the city when he started in 1977; today, there are 851.Still, Vicenza has held on to its position better than jewelry-making outposts in France, Spain and Germany, he noted, thanks to superior craftsmanship and the standard of Italian style. Vicenza must express the italianit it did in the past, he said, a lit cigarette in one hand as he sipped an espresso at his desk. The world expects expressions of beauty and quality from us.Its easy to feel the italianit of the past in Vicenza. Tourists flock to town to see Palladios harmoniously symmetrical Renaissance buildings: the basilica; the Teatro Olimpico, a 1585 marvel that recreates an ancient amphitheater as an indoor playhouse; and other Unesco-protected sites.Yet visitors might easily miss one of the most resonant examples of architecture: Vicenza in miniature, circa 1577, the year the town council commissioned Palladio to design a small model of the city. Just about two feet in diameter and with 300 tiny buildings, the model was painstakingly created in sterling silver by Vicenzas jewelers, requiring more than 2,000 hours of handwork. An offering to the Virgin Mary for the cessation of the plague, it was destroyed by Napoleons troops in 1797.But in 2011 the city had the model recreated, using its appearance in several Renaissance paintings as a guide. Today, it sits in a spotlit case at the Diocesan Museum a silent, gleaming votive to the unending gospel of jewelry-making in Vicenza.