A 450-million-year-old trilobite fossil fashioned into an amulet has been unearthed in a Roman-era dump in Spain. Likely set in metal or leather, the 1.5-inch piece is the first trilobite fossil linked to Romans and only the 11th found archaeologically. Trilobites lived in oceans 520 million years ago. Researchers suggest its wearer believed it possessed magical healing powers.