Nacre Layers (image) University of Rochester Share Print E-Mail Caption In order to make artificial nacre, Anne S. Meyer and her team use bacteria to create alternating thin layers of crystallized calcium carbonate and sticky polymer. Each layer is approximately five micrometers thick. Credit University of Rochester photo / J. Adam Fenster Usage Restrictions None Share Print E-Mail 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.