This is a lovely vintage sterling silver with black onyx and marcasite brooch!  In an oval shape with floral accents around, the center is a cabochon black onyx.  The lovely brooch measures 1 7/8" by 1 1/4",  with the stone measuring 1 1/16" by 3/4" and is clearly marked "925".  In excellent vintage condition, this piece is trendy and ready to wear!