Impregnated diampowder metalond core bit is composed of industrial diamonds scattered throughout the metallic matrix。 The diamonds are sintered with metallic matrix at very high temperature。 The matrix is made by mixing various metal powders such as bronze， copper and cobalt。 The bit is set at the bottom a drill stem， which is connected to a rotary drill。 The rotatory action of bit (protruding diamonds at the bottom) cuts the hard rocks。 Water is injected into the drill pipe， so as to wash out the rock cuttings produced by the bit。 They need to drill slowly due to the hardness of the ground being drilled； it allows exposing more diamonds for cutting action。 An actual diamond bit is usually designed for a specific rock type， with many channels for washing。

Diamond core drilling utilizes a circular impregnated diamond core bit attached at the bottom end of drill stem to cut a cylindrical core of hard solid rock。 It is commonly used when a core specimen is needed either for analysis or mining purposes。 Geologists analyze the core specimen and determine what minerals are present in that rock。 Rock that contains minerals is treated with chemicals to extract them。 Impregnated diamond core bits are also used in the construction working to create holes for pipes， manholes， and other penetrations in concrete or stone。

The hardness of the matrix is an essential factor in the selection of a bit。 A strong matrix and a large diamond is used for digging soft rock ，a medium matrix and a medium diamond is used for digging medium hard rock while a soft matrix and a small diamond is used for digging hard rock。

Scientists and engineers explore for mineral deposits (such as metals， gold， gemstone， diamond etc。) under the ground。 Minerals come mainly from rocks and， therefore， they look for rocks for mining operations。 They exploresintered metal underground with sound waves。 But the only way to obtain those minerals is drilling the ground or rock。 In these cases you have to use some drilling equipments。 There are many types of drills that are used according to the purpose of boring or the condition of the ground。