Gravel, shale, slate, what are the difference
calcareous shale, iron shale, siliceous shale, carbonaceous shale, black shale, oil shale and other iron shale may become iron Ore, oil shale can be extracted oil
feldspar clastic And other chemicals, according to the composition of their mixture can be divided into
Shale is a sedimentary rock that is complex, but has a thin sheet or lamellar joint, mainly composed of clay by the formation of pressure and temperature of the rock, but mixed with quartz
