high stone
The natural monument "Hoher Stein" right next to our beautiful Fürstenstein Castle is listed in the geotope cadastre of the Bavarian State Office for the Environment
(#275R001). The granite summit cliffs show pronounced weathering of the "Felsburg - Wollsackbildung" type with block currents in the foothills.
These were formed during the last ice age.
The wool sack weathering
Wool sack weathering is a special form of weathering that produces typical manifestations. It occurs on solid rock when certain conditions are met. This form of weathering is mostly found in granite, but it is also occasionally found in other solid rocks.
The process of wool bag weathering always takes place underground and always produces rounded shapes. The name of this weathering is derived from these round shapes, since the weathered stones once reminded people of stacked woolen sacks. In our latitudes, wool sack weathering took place mainly in the Tertiary period with its warm and humid climate more than 3 million years ago. The massive granite usually does not form a homogeneous mass, but is penetrated by fine fissures and fissures. Chemically aggressive water penetrates through these into the rock and begins to decompose it. If the rock fissures intersect approximately at right angles - which is often the case - rough cuboid blocks are thus specified. Water and acids have larger attack surfaces on the corners and edges of these blocks than on the sides. As a result, all sharp and angular parts of the rock blocks are rounded off over time, resulting in ellipsoidal boulders. By washing away the topsoil and the weathering residues, the rounded stone blocks are uncovered in the further course of the story and the process of wool sack weathering is thus ended. What remains are often adventurous-looking rock formations, which are also referred to as ROCK CASTLES - as in the legend of the HOHEN STEIN