The invention provides a tool component comprising a first layer of polycrystalline cBN material which has a rake (working) surface and a flank surface and comprises less than 70 vol % cBN; and a secondary layer across the rake surface or at least partially across the rake surface and comprising a refractory material and optionally a binder phase and optionally cBN, wherein the secondary layer has a higher resistance to crater formation than the first layer of cBN material and has a lower affinity towards iron than cBN.