From the Latin 'vernaculum' meaning local, the Vernaccia grape is often ascribed to many varieties the length of Italy.

Vernaccia di San Gimignano DOCG is its most famous form, grown around the eponymous hilltop town near Siena, Tuscany ever since the 13th century. Vernaccia di San Gimignano is a light to medium bodied dry wine, with bright citrus fruit, crisp acidity & a tangy almost salty finish.

Azzienda Agricola Casale  (Riccardo Falchini) is a respectable source.