In the same year the mining of potassium salts (Kalisalz) began at the Heinrichssegen Shaft; it had to be halted only four years later as a result of the war, after having reached a depth of just six metres.
Samal aastal alustati kaaliumisoolade (Kalisalz) kaevandamist Heinrichssegeni šahtis; see peatati vaid neli aastat hiljem sõja lõppedes, olles jõutud vaid 6 m sügavuseni.