Bentonite is naturally occurring hydrated aluminum silicate. The most important use of bentonite is based on its natural swelling property. One can surely say that bentonite is most economic natural thickener available to industries.
It has ability to absorb water several times its weight and give thick tropic fluid.
Chemically bentonite is hydrated aluminum silicate.
the greatest application of bentonite is in oil drilling. Great quantities of bentonite are used in drilling mud.
In paint industry it is used as a thickener in some cheap paints, primers, and water based coatings.
It is used in manufacture of cheap greases
limestone is a common sedimentary rock consisting mostly of calcium carbonate, caco3, used as a building stone and in the manufacture of lime, carbon dioxide, and cement. Essentially a dolomite stone possessing oil-resistant properties, limestone shows high resistance in freezing and thawing conditions.
It is generally used as limestone tiles, limestone slabs in flooring, wall cladding, vanity tops and to pave the floors of large commercial complexes, hospitals, airports, shopping malls, railway stations, parks etc.
The muted tones of limestone are perfect for today's more casual and comfortable lifestyles. Generally these soft beiges and tans, either polished or honed, is appropriate for bathrooms, fireplaces, counters and less-traveled flooring where a more informal decor is desired.
Limestone are sedimentary rocks that are formed at the bottom of lakes and seas, as silt and organic matter settle to the bottom. As more and more layers build up over thousands and millions of years, adding more and more weight, the heat and pressure cause chemical reactions to take place to harden the sediments into solid stone. The great sphinx of egypt is a masterpiece of sculpted limestone.