The invention provides a laminate capable of polishing and grinding the surface of a material having a high hardness such as diamond, sapphire or hard carbon film, rapidly and in a simplified manner with high planarity and high accuracy, utilizing the high adhesiveness to substrates, the hardness and the surface planarity that a carbon film has, but using neither diamond abrasive grains nor alkali slurry. The laminate comprises a substrate and a carbon layer provided on the substrate, wherein the carbon layer comprises a diamond fine grain provided on the substrate and crushed by impact given thereto, a formation/growth inhibiting material that inhibits the formation of an impurity inhibiting the growth of a carbon grain and/or inhibits the growth of a carbon grain, and a carbon grain, and an amount (amount per unit volume) of the formation/growth inhibiting material decreases from a lower layer toward an upper layer on the substrate side. Preferably, the formation/growth inhibiting material is an SiO2 material or an Al2O3 material, and optionally an adhesiveness-reinforcing layer comprising titanium or a titanium alloy or the like may be provided between the substrate and the carbon layer.