... are distributed in the depth of impregnated bit's matrix series.3,The matrix layer of the crown contains a uniform ... cost of diamond drilling to a minimum. The optimum diamond size, concentration and matrix type are dependent on the hardness and ... abrasiveness of the formation to be drilled. SeriesSize AvailableQ series AQ, BQ, NQ, HQ, PQ/AQTK, BQTK, BQ3, NQ2, NQ3 ...