The process of taking out stones from natural rock beds is known as quarrying of Stones. Methods of Quarrying of Stones: -
1.Digging
2.Heating
3.Wedging
4.Blasting
1. Digging – Digging or excavation of stones is carried out with the help of suitable tools such as hammer, shovels, crowbars and pick-axes Only those stones which occur in the form of detached nodules, buried in earth can be recovered by this method.
2. Heating –: In this method, the top surface of rock is heated, by placing pieces of wood, or by piling a heap of fuel over the surface for some hour. Due to unequal, upper layer of rock separates out. It is indicated by dull bursting noise. The detached portion of rock is then removed by suitable instruments This method is used, where stones are required in pieces like road metal, railway ballast.
3. Wedging – When rock bed consists of natural fissures or cracks wedging method is used. Sometimes artificial holes are drilled for wedging. In this method, if rock surface contains cracks or fissures then steel wedges or points are driven through such cracks by means of hammer. The blocks of stones are removed with the help of suitable instruments. Wedging is adopted for stratified rocks which are comparatively soft such as laterite, marble, limestone, sandstone.
4. Blasting- this method is used for hard fissure fewer rocks using explosives. In this method explosives are used convert rocks in to small pieces. The stones obtained by blasting are used in railways, concrete. Detonators and explosives like blasting powder or dynamites are commonly used in blasting. Large blocks of stones are obtained by using blasting powder but small blocks are obtained by using dynamite.