Granite, from igneous rock, is a very hard,
crystalline, and primarily composed of feldspar, quartz accompanied by
one or more dark minerals. It is visibly homogeneous in texture.
The term"Granite" means"grain"in Latin word"Granum"because of its granular nature.
Granite is the hardest building stone, and granite
slabs and granite tiles occupy a prominent place among dimensional
stones. Due to its hardness, resistance to weathering, capability to
take mirror polish, fascinating colors and textural patterns, granite
slabs and granite tiles are extremely popular.
The principal characteristics of granite also
include high load bearing capacity, crushing strength, abrasive
strength, amenability to cutting and shaping without secondary flaws,
ability to yield thin and large slabs and - above all - durability.
Due to highly dense grain, it is impervious to
stain. Polished granite slabs and granite tiles have achieved a special
status as building stones globally. Granite is also used for wall
cladding, roofing, flooring, and a variety of other interior and
exterior applications.
India is one of the largest producers of granites
blocks and processed granite slabs and granite tiles. Granites from
leading Indian exporters are listed here.
Physical Properties of Granite
In terms of its physical properties granite is a unique material. These properties lending uniqueness to granite are.
Porosity/permeability
Granite has almost negligible porosity ranging between 0.2 to 4%.
Thermal Stability
Granite is thermally highly stable, so it shows no
changes with the changing temperature. Granite is impervious to
weathering from temperature and even from the air borne chemicals. It
is the highly resistance to chemical erosion which makes granite useful
for making tanks to store highly caustic material.
Co-efficient of expansion
The co-efficient of expansion for granite varies from 4.7x10-6 - 9.0x10-6(inch x inch).
Variegation
Granite shows consistency in color and texture.
Hardness
It is the hardest building stone and hardness of granite that lends it excellent wear.
Granite Composition
Granite is formed of quartz and orthoclase or microcline. The principal constituents of granite are:
Feldspar
Quartz
Biotite
The percentage composition of each varies and
accordingly impart different color and texture to the final product.
The percentage composition of feldspar varies between 65-90%, of quartz
can extend from 10 to 60% and that of biotite lies between 10 to 15%.
Uses of Granite
Roadstone, building blocks, but has poor resistance to fire as it crumbles when exposed to intense heat.
Traditionally the main use of black granite is in
tombstones and other monumental items, and to a lesser extent for
various types of counters, especially in the financial world,
decorative applications, elegant trimmings and luxury floorings.
Stones on bolo cord slides and pendants, paperweights, bookends, lazy susan turntables, etc.
(cn-stonenet.com)
