Crystal nacre pearls by Czech brand Preciosa are a superb imitation of natural or cultured pearls. Using strict quality standards, several layers of nacre (a pearly fluid found inside pearl-producing mollusks like oysters and mussels) are deposited onto a lead free crystal base, faithfully imitating the beauty and luster of real pearls. Nacre pearls from Preciosa are highly resistant to abrasion, UV radiation and alcohol-based perfumes.