Abstract: A bit for drilling holes in rocks comprising inserts of sintered carbide, the base of which in a plane perpendicular to the edge of its drill point follows a downward convex curve along the symmetry axis of the cross-section of the insert. The insert has the shape of an quadrangle in a section perpendicular to the cross-section of the insert, the side situated nearest to the axis of the bit being inclined at an acute angle .phi., and the side corresponding to the base of the insert being inclined thereto at an angle .epsilon. determined by the relationship 90.degree.>.epsilon..gtoreq.90.degree.-.phi., wherein .phi.<30.degree.. The plane of symmetry of the insert, taken perpendicular to the cross-section of the bit is inclined at an angle .tau. determined by the relationship 90.degree..ltoreq..tau..ltoreq.90.degree.+.gamma., wherein .gamma. is the angle of incidence of the drill point of the bit.