KM# 16.1 20 MARK20.9000 g., 0.8000 Silver 0.5375 oz. ASW, 33 mm. Subject:250th Anniversary – Death of Gottfried Wilhelm Leibniz Obv:State emblem, denomination Rev: Bust right, dates below EdgeLettering: 20 MARK DER DEUTSCHEN NOTEN BANK Germany DDR 1966