Along the way you will come across some stony ground, also called Sassete, Pietraie or “Maoni” (local name), they are a
peculiar phenomenon at our latitudes and at the modest altitudes reached by Monte Pisano, as they are typical forms of periglacial environment.
These are mobile debris flows made up of angular blocks that are easily observable on the south-western side of the mountain and represent an ancient testimony of the last glacial (74,000-13,000 years ago).
In the past they were certainly more extensive than the current outcrop areas.
Their formation is linked to the type of rock that emerges, mainly green quartzites and white-pink quartzites, which tend to break into angular blocks and provide very little alteration material.
Climatic factors have played a fundamental role in the formation of the Sassaie, which represent a degradation product by cryoclasm.
Cryoclastism (from the Greek kryòs, ice and klastòs, broken) is the process of physical disintegration of a rock caused by the pressure caused by the increase in volume of water contained within the rock cracks when it freezes. The temperature range therefore favored the fracturing of quartzites, and the low humidity and low average temperature prevented a strong chemical alteration.
Cryoclastism is a phenomenon more pronounced in regions of high altitude and latitude, and is usually associated with alpine, periglacial, subpolar maritime and polar climates, but it occurs wherever freeze-thaw cycles are present.