A method of sampling a multi-layered material having a top surface and a metallic or ceramic base, the method comprising: penetrating a top surface of the material with a micro-cutting tool to a predetermined depth sufficient to include each layer of the multi-layered material and a portion of the base, without cutting through the full depth of the base; under-cutting from the depth of penetration through the base to define a micro-sample of the multi-layered material; and removing the micro-sample with each layer of the multi-layered material intact, characterized in that the micro-cutting tool comprises an end mill comprising: a major shank having a top end and a bottom end; a minor shank having a top end and a bottom end, the top end of the minor shank extending from the bottom end of the major shank, the major shank having a diameter larger than the diameter of the minor shank; the major and minor shanks (54, 52) together defining a central bore; and at least one cutter positioned at the bottom end of the minor shank; and the step of penetrating the material comprises: rotating the end mill while penetrating the material to cut into the material to the predetermined depth; flowing a coolant downwardly through the central bore toward the material; undercutting through the material by moving the at least one cutter in a perpendicular direction relative to the bore sufficient to free the micro-sample from the material, and simultaneously changing the direction of flow of the coolant upwardly through the bore towards the top of the major shank; and drawing the micro-sample with the coolant flow through the bore upwardly through a filter for capturing the micro-sample. penetrating a top surface of the material with a micro-cutting tool to a predetermined depth sufficient to include each layer of the multi-layered material and a portion of the base, without cutting through the full depth of the base; under-cutting from the depth of penetration through the base to define a micro-sample of the multi-layered material; and removing the micro-sample with each layer of the multi-layered material intact, characterized in that the micro-cutting tool comprises an end mill comprising: a major shank having a top end and a bottom end; a minor shank having a top end and a bottom end, the top end of the minor shank extending from the bottom end of the major shank, the major shank having a diameter larger than the diameter of the minor shank; the major and minor shanks (54, 52) together defining a central bore; and at least one cutter positioned at the bottom end of the minor shank; and a major shank having a top end and a bottom end; a minor shank having a top end and a bottom end, the top end of the minor shank extending from the bottom end of the major shank, the major shank having a diameter larger than the diameter of the minor shank; the major and minor shanks (54, 52) together defining a central bore; and at least one cutter positioned at the bottom end of the minor shank; and the step of penetrating the material comprises: rotating the end mill while penetrating the material to cut into the material to the predetermined depth; flowing a coolant downwardly through the central bore toward the material; undercutting through the material by moving the at least one cutter in a perpendicular direction relative to the bore sufficient to free the micro-sample from the material, and simultaneously changing the direction of flow of the coolant upwardly through the bore towards the top of the major shank; and drawing the micro-sample with the coolant flow through the bore upwardly through a filter for capturing the micro-sample. rotating the end mill while penetrating the material to cut into the material to the predetermined depth; flowing a coolant downwardly through the central bore toward the material; undercutting through the material by moving the at least one cutter in a perpendicular direction relative to the bore sufficient to free the micro-sample from the material, and simultaneously changing the direction of flow of the coolant upwardly through the bore towards the top of the major shank; and drawing the micro-sample with the coolant flow through the bore upwardly through a filter for capturing the micro-sample.