Z-contrast image of an aquamarine crystal (IMAGE) Graz University of Technology Caption A z-contrast image of an aquamarine crystal at atomic resolution using the ASTEM microscope. The yellow arrows mark caesium ions in the crystal pores. Credit FELMI-ZFE Usage Restrictions This image may only be used in context with the content of this press release. License Original 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.