... quartz, ironstone, chert, abrasive rock etc. Including impregnated diamond core bit, surface-set diamond bit, reaming shells, casing bit ... impregnated diamond bits due to drilling equipment limitations. Surface-Set Non-coring Bits are drilling for broken formation rock ... oProductShow.init( { 'aImgSrc': aBigImageSrc } ); } )(); Surface set diamond core bit NQ, HQ, PQ, NQTT, HQWL, T2, T6, NMLC, HMLC ...