Self-Assembled Colloidal Gemstones (IMAGE) New York University Caption On the left, tiny crystals are imaged using a scanning electron microscope, distinguishing the individual building blocks, which consist of spherical polystyrene beads. On the right, larger crystals are imaged with a regular iPhone camera, revealing bright colors similar to naturally occurring opals. Credit Theodore Hueckel, Sacanna Lab at NYU Usage Restrictions With credit 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.