An international team of researchers, coordinated by the STAR research infrastructure at the University of Calabria, has achieved an unprecedented result: the transformation of colorless topaz into a blue gemstone using exclusively X-rays produced by a synchrotron. The study, published in Physica B: Condensed Matter and available open access on the journal’s website, not only introduces a new technique to the field of gemological treatments but also helps clarify the physical mechanisms underlying this color change.