Introduction
The geological formation of the Cabrerès area is characterized by constant sea oscillations that define the different composition of the layers forming it.
The red layers are composed of deposited materials of continental origin (carried by rivers and streams), not yet invaded by the sea. On the other hand, with the arrival of the sea, an upper (grey) layer of calcareous sediment begins to form at the sea bottom. We know these are marine sediments because we find fossils of crabs, mussels, sea snails, shells, and nummulites (photo).
Tavertet was at the edge of one of the sea invasion stages and for a long time was a shallow marine platform with slight waves, which favored the presence of a large number of these tiny creatures (nummulites), whose fossilized shells we now find.
The name "nummulite" means "coin-stone." In Sant Julià de Vilatorta, they are called "Sant Ponç's little coins."