Elbe sandstone

Elbe Sandstone (German: Elbsandstein) describes sandstones that naturally occur in North Bohemia and those parts of Saxony within the area around Dresden. It is named after the River Elbe, which cuts through the sandstone region in a transverse valley, the Elbe Valley Zone. It reaches the surface most strikingly in the Elbe Sandstone Mountains, which are divided into the regions of Saxon Switzerland on German soil and Bohemian Switzerland on Czech territory. The term Elbe Sandstone is used in both geological and economic contexts.

In a geological sense, Elbe Sandstone includes all sandstone types that occur in the region of the Elbe Valley and were formed during the Cretaceous period. It consists mainly of quartz grains that are cemented by silica. The ratios and constituents of its accessory minerals are variable. Its deposits border on the area of the Lusatian Massif (Lusatian anticlinal zone), the Meißner Massif, the gneiss of the Eastern Ore Mountains, the Elbe Valley Slate Mountains and the territory of the Czech Republic by the northeastern foothills of the Central Bohemian Uplands and the fringe of the Eger Graben.

The bulk of the rock won in the quarries comprises sandstones with a silica cement. These are quartz sandstones, whose quartz grains have intermeshed crystal systems as a result of lithification (diagenesis) at their contact zones. Additional constituents include feldspar, glauconite and ferrous minerals of limonite ore. In the pore space of sandstones of the Cotta type there are the fine-grained minerals of illite, kaolinite and quartz. The kaolinite comes from the chemical weathering of the feldspar (kaolinization). The SiO₂ thus released contributes considerably to the mutual coalescence of the grains of sand. The pore spaces in sandstones of the Posta type for the most part contain no fillings.

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