Deposits of industrial minerals and other useful rocks Tuesday December 12th, 2017 / Raimund Schnürer / No Comments
Earthquakes: heavy earthquakes (magnitude 4.5+) Monday December 11th, 2017 / Raimund Schnürer / No Comments
Man-made caves: pits, mines and tunnels Wednesday December 6th, 2017 / Raimund Schnürer / No Comments
Production plants of the brick manufacture industry Wednesday December 6th, 2017 / Raimund Schnürer / No Comments
