Exploratory drilling of Dona lead mine Employer (client): Damavand Mining Company under Mustafafan Foundation Start date: the beginning of May 1401 End date: until the end of Aban 1401 Excavation in this mine was done to a depth of 250 meters and an angle of 15. Excavation area of ​​H size up to 170 meters and N size up to 250 meters. The type of rock is andesite, lime and dolomite metamorphosed with chert, and lime and dolomite related to Elika formation, and this variety of lithology has made this company use a wide variety of drills with different types and hardness for drilling.