Looks like studio work. Incised round plate in a modernist design with a biomorphic shape set with a small piece of polished stone. Three dangles and another piece of black stone. This piece has a partial 925 mark. The chain is marked 925, wears at 16 inches and has an additional O ring to wear at 15 inches. The pendant segment is 1 1/8 long by 1/2 inch wide. Ca., 1970 and is in very good condition.
Mid Century Sterling Silver and Black Onyx Necklace