Rochlitzer Berg

Rochlitzer Berg is a mountain of volcanic origin in Saxony, southeastern Germany. It is situated south-west of the town of Rochlitz on the river Zwickauer Mulde. Its elevation is variously given as 348.9 m NHN, 348 m HN or 353 m NN. The mountain is also known as Rochlitzer Collm.GeologyThe so-called Rochlitzer Porphyr, a rhyolitic tuff, which makes up a large part of the mountain, was formed from deposits of late explosive eruptions of a volcano about 250 million years ago. The colour of the rock is usually reddish to reddish-violet, occasionally also reddish brown to beige. Its texture is grainy and marked by many pore-like cavities (macro-pores). While the designation as "porphyry" has been passed down through history and is commonly used, it is petrographically incorrect.The tuff rock has been used since roughly a thousand years all over the region, also by Renaissance master builders Arnold von Westfalen and Hieronymus Lotter. The latter used it for the Old Town Hall in Leipzig and Augustusburg castle. More recently, it was used for facing of Stadthalle Chemnitz and the Peasants' War Panorama near Bad Frankenhausen.