E-Mail IMAGE: Electron microscope images of giant needles. Needles have a cylindrical shape and some taper toward one end of the crystal. view more Credit: Courtney Wagner, Ioan Lascu and Kenneth Livi. There are fossils, found in ancient marine sediments and made up of no more than a few magnetic nanoparticles, that can tell us a whole lot about the climate of the past, especially episodes of abrupt global warming. Now, researchers including doctoral student Courtney Wagner and associate professor Peter Lippert from the University of Utah, have found a way to glean the valuable information in those fossils without having to crush the scarce samples into a fine powder. Their results are published in Proceedings of the National Academy of Sciences.