Circa 1940's Mexican sterling silver brooch with amethyst cabochons. On either side of the central half sphere are fans of sterling silver accented with amethyst cabs.
The hallmark is very faint, but I believe it is eagle #23, Sterling Mexico, and the mark for AE in a heart shaped M. I have had their pieces before and this looks very much like their style.
Overall condition is excellent, but the locking mechanism on the clasp is missing. The pin measures 2.25 x 5/8 inches.