Tooth Surface (IMAGE) Max-Planck-Gesellschaft Caption This is a surface of a tooth, with two large scratches (dark blue lines) that have been caused by quartz particles. Credit Peter Lucas, Kuwait University 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.