This very unique souvenir Niagara Falls pin dates from the late 1940s or early 1950s, but it was not made in the US, it was made in Bavaria. Im probably the only person on the internet who can tell you a great deal about intaglio glass pins like this. Most people refer to pins like this as Goofus glass, which is incorrect as there is no such thing as Goofus glass jewelry. 
 
This intaglio glass has superb luminosity and the silver white falling water appears to be alive. The bezel, flat back mount, and bar clasp are sterling and the pin is signed sterling in old type set. The glass is thick and dense old lead glass. 
 
This pin was made in Bavaria after World War II in a region called Neu-Gablonz, or close to Ausburg. In 1991, a German woman published a book on Bohemian glass, filled with the history of glass making in this region. In her book she depicts painted intaglio glass domes that were made in Bavaria in the 1940s and 1950s. She attributes the intaglio glass method to German Johann Friedrich Reiffenstein (1719-1793) who in 1766, achieved cameo incrustations or sulfides. 
 
 The pin is medium petite in size at 1 1/4" long x 3/4" tall or 3.1 cm x 1.8 cm. The glass and the intaglio paints are in perfect condition with no chips, scratches, or scuffs on the glass and no fading or loss of paint. The back has the original fine working safety clasp and the sterling has a light patina from age. The pin is signed Sterling.
 
Comes gift wrapped and shipped in a new presentation jewelry box.