Searching for Nanodiamonds (IMAGE) Washington University in St. Louis Caption Tyrone Daulton is pictured with the transmission electron microscrope he used to search in vain for shock-synthesized nanodiamonds, evidence that a extraterrestrial object such as a meteorite killed off North American megafauna. Credit Tyrone Daulton 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.