Silver, 34mm diameter, 19.99 grams.  REPUBLIK· ÖSTERREICH· around 10 shields of arms, 50 SCHILLING in centre.  Rv. 100 JAHRE DONAUWALZER 1967  Half-length figure of Johann Strauss the younger playing violin, BODLAK below (Kurt Bodlak, engraver).  KM 2902, Schön 95.  About EF - good EF