The inlaid marble floor (opus sectile) is composed of different elements of marble, called crustae, purpose-shaped and putted side by side to define a figure or a geometric design. It is a typical decoration of the Roman Empire, then extensively resumed during the medieval period (Cosmati Masters Art), often with reuse material.
As for the mosaics, the diagnostic investigation is directed to the knowledge of the materials, especially the marble constituting the crustae, which can be characterized macroscopically, by diffraction or evaluating the isotopes and trace elements. The recognition of the marbles is very important both from a technical-artistic profile, both for the restoration intervention. May be necessary to replace some crustae with others of the same type.
Instead, from the conservative point of view is necessary to define the state of conservation of the bedding mortar, upon which depends the keeping of the floor. The techniques most suitable for this purpose are the reading of petrographic thin and cross sections, the ionic chromatography for the determination of soluble salts and the FTIR spectrometry for the identification of organic substances.