This pin dates from sometime between the 1920's and 1940's and looks to be hand done. During this period Mexican sterling pieces were stamped in raised letters SILVER MEXICO. The four silver balls are hollow at the back and three of them have very very tiny dents in the sides. The pin is set with a green turquoise cabochon surrounded by a braided setting. The pin stem is slightly bent but the clasp works well and is secure. Measures 2 3/8" X 1 1/2".