Patent ID: 8627904

Claim:
A diamond construction, comprising: a diamond body comprising a plurality of bonded-together diamond crystals forming a matrix phase, and a plurality of interstitial regions disposed between the bonded-together diamond crystals, the diamond body comprising: a first diamond region extending a depth from a surface of the diamond body being substantially free of a catalyst material used to form the diamond body, wherein the first diamond region comprises the matrix phase and in at least a portion of the plurality of interstitial spaces, the first diamond region comprises a metal carbide and an inert metal, wherein the metal carbide is fondled as a result of reaction between the diamond crystals in the matrix phase and a carbide-forming metal; and a second diamond region adjacent the first diamond region comprising the matrix phase and a Group VIII metal in the interstitial regions; wherein the interstitial regions in the first diamond region comprises a continuously decreasing gradient of the metal carbide and a continuously increasing gradient of the inert metal from the interstitial regions adjacent the surface to the interstitial regions adjacent the second diamond region, such that the interstitial regions adjacent the surface of the diamond body comprises a greater relative amount of the metal carbide and lower relative amount of the inert metal as compared to the interstitial regions in the first diamond region that are adjacent the second diamond region.