"In light of new developments, we have reconsidered our terminology used for ruby treatments," says Dr. Henry Hänni, director of the SSEF Swiss Gemmological Institute in Basel. Because ruby enhancement combines three elements—transforming color, increasing transparency, and healing fissures (or filling larger cavities)—SSEF has modified its ruby enhancement terminology, saying that judging only the presence of foreign residues neither reflects nor directly relates to the total improvement achieved. "Ruby treatment is a complex process, where heat, together with flux-like substances, acts in different ways to enhance the treated stones," says Hänni. "Heat alone may change the color and transparency of the ruby." He notes that the addition of flux-like materials, along with heat, leads in most cases to an artificial healing of fissures that can leave glassy residues in fissures or