... quartz, ironstone, chert, abrasive rock etc. Including impregnated diamond core bit, surface-set diamond bit, reaming shells, casing bit, ... size, concentration and matrix type are dependent on the hardness and abrasiveness of the formation to be drilled. ... .run.minisite.productShow(); oProductShow.init( { 'aImgSrc': aBigImageSrc } ); } )(); Diamond core bit NQ, HQ, PQ, NQTT, HQWL, T2, T6, NMLC, HMLC