Silvano Vinceti (top), head of Italy’s National Committee for the Promotion of Historic and Cultural Heritage, looks on as researchers open the tomb in the stone church floor above the family crypt of Florentine silk merchant Francesco del Giocondo at the Santissima Annunziata basilica in Florence. Photograph:  Stefano Rellandini/Reuters

Researchers opened a centuries-old Florence tomb in a search for remains that could confirm the identity of the woman whose enigmatic smile Leonardo d(...)