Layers of the potassium ore is seen on the wall of the underground gallery of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641417
Workers walk in the underground gallery of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641410
A worker operates an equipment in the underground gallery of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641407
Workers walk in the underground gallery of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641393
An aerial view of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641381
An aerial view of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641380
An aerial view of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641379
An aerial view of the Berezniki-4 potassium mine in Permsky kray, Russia, September 18, 2018.18.09.2018#5641369
