of pdc cutting elements 14 the pdc cutting elements 14 can be arranged in a plurality of spiral rows 16 arranged generally along the axial dimension of the mill body 12 the mill 10 is designed to be rotated in a selected direction clockwise when viewed from the top end 18 for the mill shown the cutting face 20 of each cutting element 14 is oriented toward the direction of rotation the distance 22 between any two adjacent cutting elements 14 in any given row 16 measured along a line parallel to the longitudinal axis of the mill body 12 is a minimum of 20 of the diameter of the cutting face 20 of either of the two adjacent cutting elements 14 as shown in fig2 the spiral rows 16 of cutting elements 14 can be paired with each such pair having a leading row 24 and a trailing row 26 with the leading row 24 being in front of the trailing row 26 relative to the selected direction of rotation the cutting elements 14 in the trailing row 26 can be aligned to follow in the cutting paths established by respective cutting elements 14 in the leading row 24 the cutting elements 14 can be substantially cylindrical with circular cutting faces 20 as.