Greywacke quarry at Collm

Greywacke was quarried here from 1835 to 1959. Greywacke is a grey to greenish-grey sandstone consisting mainly of quartz, feldspar, and numerous rock fragments embedded in a clayey matrix. This very compact, solid rock was used as a road construction material, building material, and millstone.

In the abandoned greywacke quarry, the rocks that partially comprise the 314-meter-high Collmberg can be discovered. These are the oldest rocks in the Porphyrland Geopark, which stretches between the Hohburg Hills, the Collm, the Rochlitz Hill, and the Beucha church quarry. The greywacke was deposited in a shallow sea around 450 million years ago. Subsequently, these marine deposits withstood millions of years of mountain building, Rotliegend supervolcanism, ice ages, and weathering, and are still visible today.

More information about the quarry

Please pay attention to the information provided by the municipalities and owners regarding the condition and accessibility of the geotopes.