Patterned Designs (IMAGE) Harvard University Caption The different colors in this photograph are a result of tiny variations in thickness: just 10-15 atoms of germanium separate the pink color from the violet, and another 10-15 atoms change the color from violet to dark blue. A penny is shown for size comparison. Credit Photo courtesy of Mikhail Kats and Lulu Liu 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.