Clinker : Cement clinker is a solid material produced in the manufacture of Portland cement as an intermediary product. Clinker occurs as lumps or nodules, usually 3 millimetres to 25 millimetres in diameter. It is produced by sintering limestone and aluminosilicate materials such as clay during the cement kiln stage. Clinker is primarily used to produce cement. Since it can be stored in dry condition for several months without noticeable deterioation, it is traded internationally in large amounts. Cement manufactures buy clinker for their cement plants in areas where raw materials for cement are scarce or unavailable.
Chalk : Chalk is a soft , white , porous , sedimentary carbonate rock. It is form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Chalk is mined for use in industry, such as for quicklime, bricks and builders putty, and in agriculture, for raising pH in soils with high acidity.
Bentonite : is a very old clay that has been used as a remedy for many things. The fine powder forms when volcanic ash ages. It's named after Fort Benton, WY, which has a lot of it. But it's found all over the world. It's also known as Montmorillonite clay after a region in France with a large deposit. Bentonite is the active protective layer of geosynthetic clay liners. Drilling: Another conventional use of bentonite is as a mud constituent for oil and water well drilling. Its roles are mainly to seal the borehole walls, to remove drill cuttings and to lubricate the cutting head.