Granite

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