Following the fork towards the right, we reach the surface of the large fault that constitutes Monsummano Hill's anticline. The trail is intersected diagonally by a large vein of calcite, while fragments of Selciferous limestone from the Grotta Giusti surface downhill. This stratified formation is typical of this area and includes microfossils from the sedimentation of lagoon waters during the Lower Jurassic.
On the uphill side, a limestone mass can be seen, which was formed by the sedimentation of marine waters during that same geological era. The trail leads to a disused quarry where a small fault marks the contact with the stratified red ammonite above. Extending for more than 20 meters, the quarry's western face corresponds to a single surface-layer. Following along, we come upon the Limano flinty limestone and then descend towards the trail from where a third quarry wall is visible on the left. With a north-south orientation, it corresponds to the surface of a minor fault that can be seen on the right with Posidonia marl stratifications.
Back on the trail, Val di Lima flinty limestone surfaces for a short distance. After a dozen meters, a small outcropping of Tuscan red-violet jaspers appears. The trail leads to a small quarry of Sugame marls. Continuing along the mule track that rejoins the paved road that arrives at the castle in Monsummano Alto.