Granite

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

Physically, commercial granites are Hard, Compact rocks with fine to coarse grains of metamorphic or igneous origin.

Hardness	6 to 7 on Moh's Scale
Density	2.6 to 2.8 Kg/cm3
Compressive Strength	140 to 210 N/mm2
Modulus of Rupture	15 to 25 N/mm2
Water Absorption	0.1-0.6%
Average Wear	Less then 1%
Porosity	Quite low
Weather Impact	Resistant

Chemical Properties of Granite

Chemically, they are igneous/metamorphic rocks composed of quartz, feldspar & ferromagnesian minerals like kriolite, chlorite, garnet, etc. A typical granite will have following chemical composition:

Silica (SiO2)	70-75%
Al2O3	10-15%
CaO+MgO	Less then 0.5%
FeO + Fe2O3	2-4%
Alkalies	4-6%
TiO2	Less then 0.5%
Loss On Ignition (LOI)	Less then 0.5%

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.

Ocurrances of Granite

India	Chimakurthy Mandal, Prakasham Dist, Andhra Pradesh Elandur, Kollegal Taluk, Chamarajanagar District Kesamudram Mandal, Warangal Dist, Andhra Pradesh Chinnanagarm Village, Nellikuduri Mandal, Warangal Dist, Andhra Pradesh Balugaon Taluk, Kurda District in Orissa Kulathur Taluk, Pudukkottai District of Tamil Nadu Kazipet Mandal, Warangal District, Andhra Pradesh Bolangir Taluk, Bargadh District in Orissa White Granite quarry at Jalampaly, Vizag Dist. Andhra Pradesh Marble quarry at Sidhavatam, Kadapa Dist., Andhra Pradesh Marble quarry at Umpavally, Koraput Dist., Orissa Yellow Granite quarry at Palghot, Kerala Yellow Granite quarry at Bolangir, Orissa Kummam, Karsanur, Tindivanam, Paitur, Atur in Tamil Nadu Charmarjanagar and Kollelgal in Karnataka and Warrangal in Andhra Pradesh
China	Shanxi and Shandong Hongtang, Tongian, Xiamen
Brazil	Giallo Veneziano quarry Nova Venec, Vila Pavao around 145 miles north of Vitoria, the capital of Espirito Santo Sta. Cecilia Dourado quarry, located near the village of Vila Pavao, Espirito Santo Viana, Espirito Santo
Scotland	Bunessan , Ross of Mull Aberdeen, Grampian St. Andrews, Fife
Latin America	Suriname