The Dračí skála (“Dragon Rock”, 952.5 m) is one of the best natural outcrops of porphyric biotite-muscovite to biotite granite of the older intrusive complex of the Krušné hory (Erzgebirge) batholith (large mass of igneous rock). The picturesque rock landmark is located about 1 km SSE from the Pernink railway station, which is, after the South Bohemian station Kubova Huť, the second highest located station in the Czech Republic (915 m).
The rock wall, with a length of over 100 meters and a height of 10 m, originated due to the frost weathering of the exposed rock massif at the top of the hill. The shear effects of freezing water formed frost cliffs on the sides of the outcrop. The cliffs advanced towards the top and formed an elongated wall outcrop. Both ends of the rock walls are crumbling into the accumulated blocks. Individual blocks are located on a rocky plateau around the outcrop, where they were brought by solifluction (creeping movement of soil cover on slopes). On the rocky outcrops, the original, well developed rectangular jointing is accentuated by granite weathering along cracks. The three mutually perpendicular directions of separation are combined with skew cracks. In the upper parts, the pillow jointing is occasionally developed, and the rocks consist of stacked flat rounded boulders (a prime example of this phenomenon is the natural monument “Moučné pytle” in Slavkovský les Mts.). On the surface of the granite, selective weathering ("loss") of more resistant feldspar phenocrysts can be seen in places.
In the past, the Dračí (“Dragon”) Rock was a popular sightseeing place. At present, the view is limited due to the height of the forest vegetation. In the south direction there is a nature reserve called Ocean, which is surrounded by spruce forests with extensive raised bogs containing mud sedge (a wetland plant resembling grass) and bog pine vegetation.
Fig.:
1. Stop situation in the map
2. Dragon Rock
3. Porphyric Granite