An indexable parting blade has opposite blade first and second sides, a blade peripheral edge, a central index axis, and at least first, second and third insert pockets located along the blade peripheral edge. The parting blade also has first, second and third coolant channels, each forming a coolant path from a corresponding inlet to a corresponding one of the insert pockets. Each coolant channel includes a rake outlet opening out to a rake side of its corresponding insert pocket and a relief outlet opening out to a relief side of that same insert pocket. The inlet corresponding to a given coolant channel is located further from that coolant channel's insert pocket than at least one of (a) the inlet corresponding to a different coolant channel, and (b) the central index axis.