Reliquaire de saint Lois de Toulous
France, XVe et XVII siécle.
Argent
Coll. Alessandro Castellani
Aquisition, 1879

Which can be roughly translated as:

Reliquary of Saint Lois de Toulouse
France, 15th and 17th Century.
Silver
Collection of Allesandro Castellani
Aquisition, 1879

More information on reliquaries can be found at Wikipedia and at the Metropolitan Museum of Art site.