How to Date Billion Year Old Rocks Using Radiometric Dating

Bob Greene: A new technique can quickly and non-destructively date billion year old rocks. He says it takes advantage of harmless radioactive impurities that were incorporated when rock, for example, was formed. It's not quite as accurate as the gold standard, which is using thermal ionization mass spectrometry. Greene: Still a vocal minority who think video games are to blame for school shootings.