Robertshall Mine

The Robertshall mine was an underground lignite mine in the Harburg Mountains, in the Hamburg district of Hausbruch. The mine was only in operation from 1919 to 1922, when the extraction of less productive deposits was also economically viable due to the raw material shortages after World War I. The lignite extracted was exclusively delivered to the Vereinigte Gummiwaaren Fabriken Harburg – Wien in Harburg.
In the area of the mine, there are three lignite seams: the upper seam with a thickness of up to 8.5 meters at a depth of about 17 meters, the middle seam at a depth of about 35 meters with a thickness of 4 to 10 meters, and the lower seam at a depth of 100 to 300 meters with a thickness of about four to eight meters. The groundwater level is around 17 to 17.5 m above sea level. The height of the headframe of the shaft was 31.5 m above sea level. The seam consisted of a sand-coal mixture with coal grain sizes ranging from wheat grain to child's head size, with the majority of the coal being the size of plums.

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