Patent ID: 8172012

Claim:
A polycrystalline diamond element, comprising: a substrate; a polycrystalline diamond layer bonded to the substrate along an interface, the polycrystalline diamond layer comprising: a working surface opposite the interface; a region adjacent the working surface lean in catalyzing material and extending away from the working surface to a depth; a peripheral surface located between the working surface and the interface; a substantially annular region lean in catalyzing material adjacent and extending along the peripheral surface away from the working surface a distance toward the interface greater than the depth of the region lean in catalyzing material adjacent the working surface and radially inward of the substantially annular region the substantially annular region having a radially inner periphery extending below the depth of the region adjacent the working surface lean in catalyzing material and radially inward of the substantially annular region; and a region rich in catalyzing material having a portion located radially inward of and adjacent the radially inner periphery of the substantially annular region lean in catalyzing material and at least another portion extending to the peripheral surface and located between the substantially annular region and the interface.