A method for treating a super-hard structure, the method including heating the super-hard structure to a treatment temperature of at least 500 degrees centigrade and cooling the super-hard structure from the treatment temperature to a temperature of less than 200 degrees centigrade at a mean cooling rate of at least 1 degree centigrade per second and at most 100 degrees centigrade per second to provide a treated super-hard structure. A PCBN structure produced by the method may have flexural strength of at least 650 MPa.