There are various types of stone used in construction in India and Different country also. They are in different in composition properties and strength. Some of the commonly stones which are used in India we will discuss in this article.
Following are the types of stones used in construction in India: –
- Marble
- Sand stone
- Basalt
- Limestone
- Granite
- Schist
- Gneiss
- Shale
- slat
- Conglomerate
Marble:
- Origin and composition: –it is a most common variety of metamorphic rock. It is formed from crystallized limestone by metamorphism\, chemically, it is calcareous and is chiefly composed of calcium carbonate.
- properties :-following are the properties of marble:-
- its crushing strength is from 500 to 600 kg/cm2
- the usual color of marble is white, but it is also available in different shades of colors such as grey, black, red, brown, yellow and combination of these
- it is compact and crystalline in structure due to which it can take a fine polish
- it is les durable
- It can be carved easily and thus is most suited for sculpture work.
- its specific gravity is 2.72 its weight 2720 kg/cum
- its absorption is 1 to 3%
- Chief uses:-used as building stone and in decorative panels
Sandstone:
- Origin and composition:-This stone is a common variety of sedimentary rocks mechanical origin. it is physically, stratified and chemically, siliceous in siliceous in nature, it is chiefly composed of quartz (grains of sand) bound together by a cementing material, but other minerals such as felspar, mica, magnetite etc. are also present.
- Properties:-following are the properties of sand stone:-
- it’s crushing strength is 400 to 650 kg/cm2
- It is white, grey, yellow, light brown, and red in color.
- Its specific gravity is 2.3 to 2.4. Its weight is nearly 2350 kg/cu m.
- Chief uses: –general walls building flagstone.
Slate:
- its crushing strength varies from 700 to 2100 kg/cm2
- it is hard tough and is least absorptive
- It also offers good abrasive resistance.
- It is a good heat and electrical insulator.
- Its water absorption varies from 0.5 to 1%.
- Following are the uses of slate:-
- It is a valuable material for roofing and black boards.
- Thick slabs of harder variety of slates are used for flooring steps shelves mental pieces sills of doors and window etc.
- slate a available at the available at the following localities in India: – simla, kangra, gurgaon, Gurdaspur, Alwar, Rajasthan, (MP) (Haryana) (Gujarat
Basalt:-
- Origin and Composition:these stones are the common varieties of igneous rocks they are formed by solidification of lava on the earth’s surface due to volcanic eruption. Some basalts develop step like appearance and are known as traps. They are chiefly composed of silica, alumina and felspar.
- Properties:-Following are the properties of basalt and trap
- Their crushing strength is 700 to 850 kg/sq.cm.
- They are hard and tough
- They are greenish grey to dark grey in colour.
- Their specific gravity (2-9 to 2.96) is more than that of granite their weight is nearly 2900kg/cm3.
- They are available as a vast deposit of basaltic rock, near the western Ghats of India, known as Deccan trap. They are also available at Raajmahal Hills (Bihar) known as Raajmahal Trap. Varieties of basalts like, Bombay Basalt, Blue basalt, red basalt and yellow basalt are found and used in Maharasatra, Gujarat etc.
Limestone:-
- Colour:- White light grey to light buff.
- Texture:- fine to crystalline, may have fossils
- Parting :-parallel to beds: also may have irregular fractures.
- Hardness: – fairly soft steel easily catches
- May show fossils.
- All lime stone are of sedimentary origin and have for their principal ingredient carbonate of lime.
- When clay is present, the stone is called argillaceous limestone; when silica predominates, siliceous limestone; when iron is prevalent, ferruginous limestone; when magnesia is present to the extent of 15 per cent.
Granite:-
- Granite is one of the most valuable stones for construction purposes. Although the quality of granite varies according to the proportions of the constituents and to their method of aggregation, this kind of stone is generally durable, strong, and hard.
- The hardest and most durable granites contain a greater proportion of quartz and smaller proportion of feldspar and mica. Feldspar makes granite more susceptible to decomposition by the solution potash contained in it, potash feldspar being less durable than lime or soda feldspar.
- Because of its uniform structure, granite can be quarried in large blocks. The rift, the grain, and the joint planes are advantageous in quarrying, as it is very difficult to cut granite in other places. The uses for which granite is suitable depend on the texture of the stone. Medium-grained stone is best fitted for building construction. Fine-grained stone can be carved and polished.
Schist:-
- Schist has a more crystalline structure than slate, and the crystals are easily seen. It is composed chiefly of minerals that cleave readily, such as hornblende,mica, etc., mixed with a variable amount of granular quartz and feldspar. The presence of the cleavage minerals produces a fine cleavage or foliation, called schistosity.
- Schist is sometimes used in building construction but it disintegrates very rapidly and is not durable. It should always be set with the planes of schistosity horizontal.
Gneiss –
- Gneiss is a coarse-grained laminated rock.
- It is formed by metamorphism of either sedimentary or igneous rock.
- It is often used as structural material and as concrete aggregate.
Shale –
- Shale is a typical clay rock that splits readily in lines parallel to the bedding.
- Sand and lime carbonate are always present in this stone and, with increase of either, the rock grades into shaly sandstone or shaly limestone.
- Shale is used for light traffic roads and in the manufacture of brick,tile,and other burned clay products, but it is not suitable for concrete aggregate.
Conglomerate –
- Stratified rock composed of rounded pebbles of any material, such as limestone, quartz, shale, granite grains, feldspar, etc., cemented together is known as conglomerate.
- When the pebbles are quartz with siliceous binding the rock is strong and hard to quarry or dress.
- When the interstices between the pebbles are not filled by the binder, the rock is very porous, and may hold great amounts of ground water.
- This stone is seldom used in building construction
