A method of producing a composite diamond abrasive compact includes the steps of forming an unbonded assembly comprising a cemented carbide body (10), a layer (18) of catalyst metal on a surface (20) of the carbide body (10), a layer (22) of carbide particles, alone or in admixture with other particles, on the catalyst metal layer, and a layer (24) of diamond particles on the carbide layer (22) and subjecting the unbonded assembly to conditions of elevated temperature and pressure at which diamond is crystallographically stable to form a composite diamond abrasive compact.