The presence of vaterite in bonding mortars of marble inlays from Florence Cathedral

Two kinds of bonding mortars of marble inlay decorations coming from the façade of the Cathedral of Florence (Italy) were studied by XRD and FTIR. Vaterite, one of the three polymorphous phases of CaCO3, was found as the prevalent mineral in the light ochre mortars. The FTIR analysis demonstrated that the spectrum of vaterite reported in literature is a mixture of vaterite and amorphous calcium carbonate.