Three Balls (IMAGE) University of Zurich Caption The three leather balls with diameters between 7.4 and 9.2 cm are between 3200 and 2900 years old. Credit (Picture: UZH) Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.