Such a beauty! I found this and the other milagro I'm listing at an estate sale in Saratoga, NY, where it lived in the collection of a peace corps worker and world traveller that, fittingly, included an abundance of carved masks. Late 19th/very early 20th century and Italian, I believe, make of what looks like silver foil with a gold finish on the face of it. To my eye just a gorgeous thing, made all the more special by a signature on reverse (clearly, based on the handwriting, early to it)--suggesting it indeed was used as an offering. ( Milagros/ex votos like this were made as religious folk charms and used as votive offerings, frequently attached to altars, shrines, and sacred objects found in places of worship.) Some losses to the trim along the top as evident, which just feels all of a piece with it. 

6 1/2" x 4". Losses along the top as noted and documented but not especially fragile. Beautiful patina and presence.