In the central bay, the flooring is made of light-coloured and grey limestone paving stones, sourced from a quarry on one of the slopes of the nearby Rocca. This stone is called Lumachella. In contrast to the bright colours of the mosaics, the dark colour of the flooring gives it a more majestic and severe appearance. Ideal for paving, steps and basalt, lumachella is a biolith with a high concentration of fossil shells.
