On April 24, 2008, a group led by Marinov at Hebrew University of Jerusalem claimed to have found single atoms of unbibium -292 in natural thorium deposits at an abundance of 10 to 10 relative to thorium. This was the first time in sixty-nine years that a new element had been claimed to be discovered in nature, after Marguerite Perey 's 1939 discovery of francium. The claim of Marinov et al. was criticized by a part of the scientific community, and Marinov said he submitted the article to the journals Nature and Nature Physics but both turned it down without sending it for peer review. The unbibium-292 atoms were claimed to be superdeformed or hyperdeformed nuclear isomers, with a half-life of at least 10 years.